Food Technology
Akram Arianfar; Mahtab Moradnia; Zahra Sheikholeslami; Ali Mohamadi Sani
Abstract
Introduction: Donut is a type of sweet fried snack that was produced as fermented and deep fried. The deliciousness and high energy of the donut has made it very popular among sweet products made from wheat flour. The lack of wheat and its sensitivity to changes in weather conditions as well as bad economic ...
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Introduction: Donut is a type of sweet fried snack that was produced as fermented and deep fried. The deliciousness and high energy of the donut has made it very popular among sweet products made from wheat flour. The lack of wheat and its sensitivity to changes in weather conditions as well as bad economic conditions in recent years requires that research in the field of replacing wheat flour with other grains. Quinoa is a rich source of protein (the essential amino acids lysine, methionine, cysteine, and threonine), magnesium, fiber, vitamin B, potassium, and other minerals such as iron. Quinoa seeds have less starch than other grains (wheat, barley, corn, and rice). The value of dietary fiber in quinoa is much more in comparison to other grains, it had about 31% insoluble fiber. Also, as a source of phytoestrogens, it prevents cancer, cardiovascular diseases, and osteoporosis. The main problem with quinoa used for human food is the presence of saponin in the outer shell of the seed. Saponins are considered anti-nutritional agents due to their hemolytic activity on red blood cells, bitterness, foaming ability, and inhibition of enzymes. Therefore, the most important step for using quinoa in food products is to remove saponin. The other problem with using saponin is too bitter hence causing bloating and heartburn. Ths study aimed to choose the best saponinization method from quinoa and the possibility of using the saponinization quinoa instead of wheat in donut formulation and investigated the quality, texture, and sensory properties of the donuts.Materials of methods: The methods for saponin removal include (maceration, microwave, ultrasound, wet method, and a combination of wet and dry method) were compared. Donuts were produced with quinoa flour at two levels of 20 and 40%. The Fiber, ash, and protein values of wheat flour, saponinized quinoa flour, and donuts with different levels of saponinized quinoa flour were measured. The effect of replacement wheat flour whit saponinized quinoa flour on oil absorption, texture, SEM, and sensory properties of donuts evaluated.Results and Discussion: A comparison between different methods of saponinization indicated that the ultrasound method had the minimum efficiency in saponin removal and the highest amount of saponin removal was in the wet and dry combined method, followed by the maceration method. The difference between the combined method and massage was not significant and had the most influence in extracting saponin from quinoa flour. Of course, the massage method is important from the point of view of the economy due to the long time of the process and the production of a lot of waste water so this method had the loss of nutrients in the quinoa. The highest amount of protein, fiber, and ash was obtained in saponinized quinoa flour and a donut containing 40% quinoa flour. The amount of firmness, elasticity, SEM, and sensory properties in the sample with 20% quinoa flour had similar characteristics to the control sample, but increasing the amount of quinoa flour reduced these factors. The oil absorption percentage in donuts containing 40% quinoa flour was higher than in other samples. The results of using saponinized quinoa flour on the sensory characteristics (color crust and crumbs, taste, smell, texture and overall acceptance) of donuts showed that donut with 20% quinoa was similar to the control sample and was acceptable for panelists but increased the concentration up to 40% wasn’t pleasant. Conclusion: In this study, the saponinized quinoa flour used in donut formulation to increase the nutritional value and reduced the calories of donuts also overcame the challenges of wheat shortage. The saponinization methods were compared to choose the method with the highest saponin removal. Then donut with saponinized quinoa flour was prepared. The use of saponinized quinoa flour instead of wheat flour increased the nutritional value of donuts. Adding saponinized quinoa flour to the donuts formulation significantly declined the oil absorptions. Generally, the donuts containing saponinized quinoa flour had relatively similar sensory properties to the donuts with wheat flour (commercial donuts). Therefore, it seems that saponinized quinoa flour could be used successfully to improve the nutritional value of donuts and also consumers' acceptance.
Food Technology
Aliakbar Gholamhosseinpour; Ali Karimi Davijani; Mostafa Karami
Abstract
Introduction: Cheese is the general name of a group of fermented dairy products that are produced all over the world in a variety of flavours, textures, and shapes. This product contains various proteins, minerals, and vitamins, all of which add to its high nutritional quality. White-brined cheeses are ...
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Introduction: Cheese is the general name of a group of fermented dairy products that are produced all over the world in a variety of flavours, textures, and shapes. This product contains various proteins, minerals, and vitamins, all of which add to its high nutritional quality. White-brined cheeses are soft cheeses that ripen in brine. Today, brined ultrafiltered cheese, as a popular product, has allocated a broad consumer market in our country. The use of thermal processes to prolong the shelf life of foods has long been considered, but these methods lead to a decrease in nutritional value and product quality. Emerging non-thermal technologies, including ultrasound, pulsed electric field, high hydrostatic pressure, cold plasma and ozone have revolutionized the food processing sector. These processes can improve the safety and quality of food products and increase their shelf life by reducing food spoilage. In addition to increasing food storage time, these technologies are expanding in the industry due to reduced energy consumption. Ozone is one of the most effective disinfectants known that does not leave any dangerous residue on food or other surfaces in contact with it. Ozone treatment does not require heat and therefore saves energy. Ozonation, as a novel technology, is widely used in preserving meat, processing oysters, inhibiting microbial growth, and oxidizing phenolic compounds. Ozone has been mainly used in the dairy industry to reduce or inhibit the growth of pathogenic or spoilage microorganisms, in contrast, its effect on the non-microbial properties of dairy products has not been studied much.Materials and methods: Cheese production was carried out by ultrafiltration technology in the Hamedan Pegah dairy complex (Hamedan, Iran). The starter culture used in cheese production was R708 (containing Lactococcus lactis subsp. Cremoris and Lactococcus lactis subsp. Lactis), which was obtained from Christian Hansen, Denmark. Microbial renin enzyme (Proteria, Handry company, Belgium) was also used for coagulation. Analytical grade chemicals were also purchased from Merck, Darmstadt, Germany. Ozone gas at concentrations of 2 and 5 ppm was used in different stages of brined ultrafiltered cheese production and then the samples were subjected to physicochemical (total solids (TS), ash, pH, salt, protein, fat, acid degree value (ADV)), microbiological and organoleptic (based on the 5-point hedonic scale) analyses at 35-day intervals during a ripening period of 105 days. Ozone treatments were: Ozonization of concentrate simultaneously with starter inoculation (OA), Ozonization of concentrate before starter inoculation (OB), Ozonization of concentrate (before starter inoculation) and brine (OC), Ozonization of brine (OD) and control (C). Statistical analysis (One-way ANOVA and Duncan) was performed at a significance level of 95% by the SPSS package program (v. 20.0, Chicago, IL, USA).Results and discussion: Based on the results, the amounts of total solids, ash, salt, ADV and syneresis of cheeses increased significantly (p ≤ 0.05), while the protein and fat contents of the samples decreased significantly (p ≤ 0.05) during the ripening period. The pH of the samples decreased from day 0 to 35 and then increased in most samples until the end of the ripening period. The total counts in the samples increased initially until day 70 but then decreased until the end of the ripening period. In general, during the ripening, cheeses treated with 5 ppm ozone had lower microbial load and higher lipolysis compared to samples treated with 2 ppm ozone. In addition, in most treatments, the sensory scores of cheeses at the end of the ripening period were significantly (p ≤ 0.05) higher than those at the beginning of the ripening period. Although the use of ozone treatment was able to improve some of the sensory properties of the cheeses, in general, this increase was not significant compared to the control, especially at the end of the ripening period.The positive microbial and physicochemical effects of ozone treatment on cheese samples increased the shelf life of brine cheese up to 105 days (30 days more than usual) without having a negative effect on its sensory properties. Therefore, ozone can be used as a non-thermal treatment to increase shelf life and improve some physicochemical characteristics of cheese.
Food Technology
Elnaz Milani; Zahra Dehghan; Neda Hashemi
Abstract
Abstract:1 Introduction: Gastrointestinal diseases are very important among human societies, especially in developing countries. One of these diseases, celiac disease, is the result of the interference of gluten in food, the body's immune system, genetics and environmental factors. Therefore, it is necessary ...
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Abstract:1 Introduction: Gastrointestinal diseases are very important among human societies, especially in developing countries. One of these diseases, celiac disease, is the result of the interference of gluten in food, the body's immune system, genetics and environmental factors. Therefore, it is necessary to provide a solution for the production of gluten-free products and also to improve their quality. The increase in the nutritional knowledge of the people of the society has caused the development and production of healthy food products for certain groups to have a growing trend. Baked products such as cookies are very popular among the society because of their textural characteristics as well as flavoring and attractive colors. Therefore, their enrichment is of interest. Most commercial gluten-free bakery products are based on pure starch or the combination of corn starch with gluten-free flour, which is associated with dryness and sandiness in the product. Materials and methods: The aim of this research wass to investigate the functional characteristics of non-extruded and extruded chickpea flour samples and then the effect of adding different levels of it at three levels of 0, 20 and 40% on physicochemical characteristics, textural characteristics, Lightness, porosity and sensory using completely randomized factorial design. The blend of chick pea flour- xanthan gum was extruded by a parallel twin-screw extruder (Jinan Saxin, China). Process was applied at die diameter of 3 mm, and extrusion temperature of 140 ℃. The chemical composition of raw materials was measured by standard AOAC (2000) methods. The hardness of cookies was measured using Texture Analyzer (TA plus Ametek, UK). The cylinder steel probe (2 mm diameter) was set to move at a speed of 1 mm/s The samples were punctured by the probe to a distance of 10 mm. The color parameters L* (lightness), a*(redness), b*(yellowness) values of the samples were determined by the Hunterlab machine (Reston VA, US) (Rhee et al, 2004). Water absorption index in terms of grams of bonded water was calculated by the sample. Sensory evaluation was performed using a 5-point hedonic test. Results and discussion: In general, gluten-free products are unable to store carbon dioxide gas due to the lack of a coherent and uniform gluten network, which causes an increase in volume. As a result, the product is small in volume and the structure of the crumb is compressed. The extrusion baking process had a high potential to improve cookie quality; In such a way that the addition of extruded chickpea flour increased the porosity of the cookie samples, the results of the texture analysis show that the addition of extruded chickpeas up to a minimum of 40% improved the texture of the cookie and also increased its shelf life. Also, the sensory test results showed the favorable effect of adding extruded chickpea flour up to 20%. concequently, by summarizing the results of physical and sensory tests, it was determined that cookies with appropriate sensory and quality characteristics can be produced using 40% of extruded chickpea flour. Peas, and especially extruded peas, due to their protein and dietary fiber content, high water absorption ability, while maintaining moisture, reduced the hardness of the cookie texture. Considering the increase in demand for gluten-free products, it seems that enriching these products with nutrients such as chickpea flour can be an alternative method to improve the nutritional value of these products. Adding legumes is a good way to increase the consumption of legumes, which are rich in the amino acid lysine. Legumes, especially pea seeds, have high nutritional value and functional characteristics, and including them in the diet by adding them to bakery products is a good way to increase their consumption. The use of chickpea flour as a nutrient source in cookie formulation increases the nutritional value, reduces the glycemic index and improves the variety of such products.
Food Technology
Ali Hashemi; Jafar Milani; Ali Motamedzadegan; Sepide haghighat
Abstract
Introduction: Due to the low amount of prolamin, rice flour is the most suitable raw material for preparing food for patients with celiac disease. Particle size classification and thermal treatments are among the physical methods to improve the functional characteristics of gluten-free flours and as ...
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Introduction: Due to the low amount of prolamin, rice flour is the most suitable raw material for preparing food for patients with celiac disease. Particle size classification and thermal treatments are among the physical methods to improve the functional characteristics of gluten-free flours and as a result, improve the quality of the products obtained from them. Particle size can increase the quality of gluten-free products by affecting the physicochemical properties of flour during hydration. Dry heat treatment and moist heat treatment are common techniques for physical modification which, depending on the intensity of temperature and storage time, lead to the improvement of gluten-free products by modifying starch grains, aroma, and flavor, and reducing microbial load. Considering that the effect of rice flour particle size on the quality of gluten-free bread has not been studied so far, in the current research, by dividing rice flour into particles with sizes of 180, 150, and 125 microns and using moist and dry heat treatment, it is possible to Improving the functional characteristics of rice flour and improving the quality characteristics of gluten-free bread were investigated. Materials and Methods: The content of moisture, pH, ash, and protein of rice flour was measured using AACC standard method (2000) and the total amount of starch was measured by the alkaline extraction method and the amount of starch damage was measured by non-enzymatic rapid method. To classify the size of the particles, waxy rice flour was divided by a shaker sieve with different sizes of 180, 150, and 125 microns, then under the influence of dry heat treatment for 2 hours and moist heat treatment with humidity, 25% for 5 hours at a temperature of 110 degrees. Celsius was placed. To produce gluten-free bread, the formulation used by Haghighat‐Kharazi in 2020 was used with a slight change. Ingredients for gluten-free bread formulation for 100 grams of rice flour included 125 ml of water, 4.5 grams of sugar, 2 grams of salt, 6 grams of vegetable oil, 3 grams of yeast, and 2 grams of xanthan gum. Bread tests, which include weight loss, specific volume, oven spring, Crumb crust ratio Shape index, porosity, crust and Crumb color, and bread texture analysis were studied to evaluate the quality of bread. Finally, the factorial test was used to investigate the effects of particle size and heat treatment of rice flour, and Duncan's multiple range test was used to compare the means at the 5% probability level.Results and Discussions: The results showed that the effect of particle size on weight loss, specific volume, oven spring, Crumb to crust ratio, crust, and Crumb color parameters, and bread texture was not significant (p>0.05). Regarding the sample volume index, C80 and DHT120 significantly had the lowest volume index (p<0.05). The HMT80-treated sample significantly increased the weight loss, and the moist heat-treated samples significantly increased the specific volume and the core to shell Crumb (p<0.05). In this study, the sample treated with HMT 120 had the highest volume index. moist heat treatment and dry heat significantly led to a decrease in brightness and an increase in the yellowness of the crust and Crumb of the bread compared to the control sample, but there was no change in the amount of redness (p<0.05). Moist heat treatment samples had the lowest hardness and Chewiness in this research compared to the control sample and the dry heat treatment sample. In general, the sample obtained from 125-micron particles and moist heat treatment led to the improvement of gluten-free bread quality.
Food Technology
Vahid Hakimzadeh; Fatemeh Ghorbanpour; Hassan Rashidi
Abstract
Introduction: One of the relatively new dairy products is cheese sauce, which can increase the consumption of cheese per capita and replace unhealthy sauces. Functionality process by adding useful compounds to food while maintaining its appearance improves properties of foods. Nowadays, due to the importance ...
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Introduction: One of the relatively new dairy products is cheese sauce, which can increase the consumption of cheese per capita and replace unhealthy sauces. Functionality process by adding useful compounds to food while maintaining its appearance improves properties of foods. Nowadays, due to the importance of compounds such as essential fatty acids, antioxidants and fiber, the demand for consuming products containing these compounds in the diet is very high. Date seed extract contains fiber, antioxidants, lignans and essential fatty acids. On the other hand, whey also has many nutritional properties. The purpose of this research is to prepare cheese sauce using such compounds so that while preparing a useful product, it is possible to prevent the wastage of valuable by-products. Material and Methods: In this research, the effect of Date kernel extract in amounts of zero (control), 5 and 15% to cheese sauce formula in the presence (15%) and absence of whey on the physicochemical characteristics of cheese sauce powder samples was investigated. The organoleptic properties of samples, also were studied in 5-hedonic form. All experiments were done based on completely randomized block design and in three replications. Duncan's test was used to compare the average dataResults and Discussion: The results showed that the addition of whey and date kernel extract to the cheese sauce significantly increased the characteristics such as dry matter percentage, powder solubility, phenolic compounds, antioxidant property and viscosity compared to the control sample. But on the other hand, the increase of Date kernel extract and whey in amounts of 15% decreased the amount of protein in cheese sauce. The results of the sensory properties of the samples also showed that the highest acceptability was related to the sample with 5% of seed date extract in the presence of whey.
Food Technology
Parisa Feizi; Yahya Maghsoudlou; Hoda Shahiri Tabarestani; Seyed Mahdi Jafari; Amir Bahri
Abstract
Astaxanthin is a widely used carotenoid pigment in the food industry which is extracted from various natural and synthetic sources. This study focuses on comparison the extraction of astaxanthin under soaking conditions for 24 hours with organic solvent (combination of ethanol with ethyl acetate), green ...
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Astaxanthin is a widely used carotenoid pigment in the food industry which is extracted from various natural and synthetic sources. This study focuses on comparison the extraction of astaxanthin under soaking conditions for 24 hours with organic solvent (combination of ethanol with ethyl acetate), green solvent (microemulsion of ionic liquid in water) and vegetable oil (sunflower oil) from shrimp (Fenneropenaeus merguiensis) and Gammarus (Pontogammarus maeoticus) . Ionic liquid microemulsion in water was considered as a new solvent for astaxanthin extraction. Determination of density, conductivity and diameter were the characteristics of microemulsion test. In extraction, 5x, 12.5x and 20x solvent ratios were used for the sample and compared with the control sample.The best method and conditions for astaxanthin extraction and the best source for extractionby using solvents and the highest amount of astaxanthin were determined and ratios of solvent to sample 5 times, 12.5 times and 20 times and in order to analyze the results and compare the average SPSS software was used , comparison based on highest amount of extracted astaxanthin was measured with a spectrophotometer. The content of total carotenoids, percentage of astaxanthin recovery, DPPH radical scavenging activity were other tests that were performed to check the extracted astaxanthin. According to the results, the density of the microemulsion was determined in the range of 0.97151 g/cm3, its diameter was 15.8 nanometers and the conductivity was 312 microsiemens at a temperature of 27.1 degrees Celsius. The results of astaxanthin extraction with different solvents in the comparison with control solvent were statistically significant (p < 0.05). According to the results obtained from the extraction of astaxanthin from two sourcesof shrimp and gammarus , shrimp was selected as the source with the highest amount of extracted astaxanthin. The use of green solvent (ionic liquid microemulsion in water) in a 12.5 times ratio of solvent to sample was also chosen as the optimal method. The amount of astaxanthin extracted under optimal conditions was 77.44 ± 1.09 mg/ml. The results of DPPH radical inhibition by astaxanthin extracted using ionic, oily and organic solvent compared to synthetic antioxidant BHT showed that antioxidant activity increases with increasing concentration of astaxanthin, but this increase was always lower than BHT.In general, the results of this research show that the use of microemulsion based on ionic liquids is a suitable alternative to conventional methods in extracting and recovering astaxanthin from natural biological sources.
Food Technology
Bahareh Shabanpour; Parastoo Pourashouri; Aniseh Jamshidi; Kaveh Rahmani farah; Akbar Vejdan Taleshmikaeil
Abstract
Introduction: In the present study, surimi was used in combination with different percentages of carrageenan, alginate and xanthan gums in order to simulate breaded shrimp and produce shrimp nugget with a texture similar to breaded shrimp. Materials and Methods: Shrimp nuggets were prepared from surimi ...
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Introduction: In the present study, surimi was used in combination with different percentages of carrageenan, alginate and xanthan gums in order to simulate breaded shrimp and produce shrimp nugget with a texture similar to breaded shrimp. Materials and Methods: Shrimp nuggets were prepared from surimi obtained from silver carp in combination with additives and different percentages (0.5, 1, 1.5 and 2) of carrageenan, alginate and xanthan. Then, they were battered and breaded after setting in 35°C. Physical, chemical, color and sensory analysis were performed on the several samples of shrimp nuggets in comparison with the control sample (battered and breaded shrimp). Results and Discussion: Based on the results, the amount of shrinkage decreased in all samples in comparison with the control (p < 0.05). Shrimp nuggets containing xanthan and alginate showed a lower amount of fat than control sample and samples containing carrageenan (p < 0.05). The highest amount of pH value was observed in the control sample and the sample containing 2% alginate was showed the highest amounts of water holding capacity. The highest value of texture analysis including hardness, springiness and adhesion were observed in the control samples, the samples containing carrageenan and the one containing alginate, respectively (p < 0.05). The sample containing 1% carrageenan showed the highest amount of the sensory attributes of taste, smell, texture and overall acceptance, but compared to the control, there were not any significant difference (p ˃ 0.05).
Food Technology
Mahshad Lavarsetagh; Nafiseh Zamindar; Yasaman Esmaeili
Abstract
Color is the most important indicator of the quality of food that affects consumer acceptance. In order to replace the color lost during the process, increasing the existing color and minimizing variation during processing; natural colors, synthetic and inorganic colorants are added to the food. Red ...
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Color is the most important indicator of the quality of food that affects consumer acceptance. In order to replace the color lost during the process, increasing the existing color and minimizing variation during processing; natural colors, synthetic and inorganic colorants are added to the food. Red beet is one of the most important natural sources of color; In this study, the overall results showed that increase in the extraction pH and time, increased the extraction of betacyanine and betaxanthine. It would be better to extract betacyanine at temperatures below 25 ° C since this pigment is sensitive to high temperatures and at the temperature above, 25 °C will be destroyed. The maximum yield was observed when pH value, temperature and time were 5, 21 °C and 20 min, respectively. Comparison of experimental and predicted values of the proposed responses at the proposed optimal point by t-test showed no significant difference (p< 0.05). Quadratic model was suggested for the responses and lack of fit was not significant (p<0.05). The extraction of betaline from red beet using ultrasonic method causes the reduction of time, temperature, energy and solvent consumption. The maximum yield was observed when pH value, temperature and time were 5, 21 °C and 20 min, respectively. Comparison of experimental and predicted values of the optimal points showed no significant difference by t-test (p< 0.05).
Food Technology
Hoda Ghorbanzadeh; Jafar Milani; Ali Motamedzadegan
Abstract
IntroductionWith the growth of the population and more demand for obtaining food and supplying the required food, the interest in the cultivation and consumption of edible mushrooms has increased. Since 1990, the world has focused on the mushroom production industry. In recent years, mushrooms have become ...
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IntroductionWith the growth of the population and more demand for obtaining food and supplying the required food, the interest in the cultivation and consumption of edible mushrooms has increased. Since 1990, the world has focused on the mushroom production industry. In recent years, mushrooms have become one of the most important food and medicinal sources. One of the largest species of edible mushroom is button mushroom (Agaricus bisporus), which has high nutritional and medicinal value. Button mushroom has high nutritional value due to the presence of things such as fiber, carbohydrates, protein, amino acids, minerals, vitamins, etc., and it also has antioxidant, anti-cancer, and anti-diabetic properties. This food has shown good health properties for humans. The quality of button mushrooms is determined by their color, texture, and taste. Color is the first characteristic that is perceived by consumers. Browning is one of the main reasons for the loss of mushroom quality, which reduces the commercial value of mushrooms. One of the most used methods today is the use of edible coatings for perishable foods, these coatings almost prevent the penetration of oxygen, depending on the type of coating used, and reduce the loss of moisture during storage. Chitosan has functional characteristics such as antimicrobial and antioxidant properties, and as an edible film, it can be considered a very good carrier to be combined with antioxidant and antimicrobial agents.Materials and methodsTo make chitosan solutions, first, each type of chitosan (70% deacetylated, 80% deacetylated, 90% deacetylated, and 100% deacetylated) was weighed in amounts of 0.5g, 1g, and 2g. then it was dissolved in 100 ml of 0.5% acetic acid solution and stirred for 12 hours at a speed of 1000 rpm at room temperature to dissolve uniformly. After 12 hours, each sample It was centrifuged for 15 minutes at 6000 rpm at 25 °C to separate the undissolved material. Mushrooms were prepared freshly harvested, washed with water, and then excess moisture was removed. After sorting and screening in terms of size and approximate weight, the mushrooms were added to 0.5%, 1%, and 2% chitosan solutions without being sliced and were immersed in the solution for one minute. The control sample was immersed in 0.5% acetic acid solution for one minute. After that, the mushrooms were air-dried at room temperature for one hour, and at the end, their excess moisture was removed with a tissue. The mushrooms were placed in 18*14 size polyethylene zip-top bags and stored in a refrigerator at 4°C. The effects of chitosan coating on weight loss, mushroom color and browning index, enzyme activity, texture, and total phenolic compounds were studied.Results and discussionThe results indicated that in maintaining the amount of total phenol, controlling the peroxidase enzyme activity, the degree of firmness of the mushroom during storage and the amount of gumminess, the best treatment was chitosan with a deacetylation degree of 70%, while in controlling the weight loss, the activity of poly Phenol oxidase and sensory test, chitosan treatment with 100% and 90% deacetylation degree had better results, and in terms of browning index and texture, chitosan treatment with 80% deacetylation degree showed better performance. This study showed that the use of chitosan coating can be effective in maintaining the characteristics of edible mushrooms.ConclusionsThe spoilage of edible mushrooms happens in a short time, and the storage of mushrooms has become one of the most important things in mushroom production. Coating edible mushrooms is one of the suitable methods to increase the shelf life of edible mushrooms. In this research, chitosan with four degrees of deacetylation and three different concentrations was used as a coating for edible mushrooms. The results indicated that coating the mushroom with chitosan could delay the occurrence of spoilage and change its color or texture.
Food Technology
Aliehsadat Rafaathaghighi; Leila Jafari; abdolmajid Mirzaalian Dastjerdi; Farzin Abdollahi
Abstract
Indian jujube fruit (Ziziphus mauritiana Lam.) is a perishable tropical fruit with high nutritional value. In the present study, in order to increase their storage life, Indian jujube fruits were treated separately with alginate (Al) and Zataria multiflora essential oil (ZEO) (0.5 and 1.0%), or in combination ...
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Indian jujube fruit (Ziziphus mauritiana Lam.) is a perishable tropical fruit with high nutritional value. In the present study, in order to increase their storage life, Indian jujube fruits were treated separately with alginate (Al) and Zataria multiflora essential oil (ZEO) (0.5 and 1.0%), or in combination with Al and ZEO, and then were stored at 6±1 °C and 90-95% RH for up to 28 days. The results showed that all the postharvest treatments maintained the fruit quality as compared to the untreated control. The Al + ZEO treatment was effective in reducing the rate of respiration. This combined treatment resulted in lower levels of percent weight loss, decay, and firmness of fruit tissue during storage. Moreover, coated fruits contained higher levels of ascorbic acid compared to untreated fruits. These results showed that applying a combination of Al and ZEO can assist in delaying Indian jujube fruits' senescence process, and can increase their storage life.
Food Technology
Mohammad Hadian; Mostafa Mazaheri Tehrani; Mohsen Ghods rohani
Abstract
IntroductionDoogh is a fermented dairy product that is produced by blending yogurt with water and some salt. This fermented beverage is widely consumed as a refreshing drink in Iran and other Middle East countries. Doogh is a source of calcium needed by the body on a daily basis and contains B vitamins ...
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IntroductionDoogh is a fermented dairy product that is produced by blending yogurt with water and some salt. This fermented beverage is widely consumed as a refreshing drink in Iran and other Middle East countries. Doogh is a source of calcium needed by the body on a daily basis and contains B vitamins that are effective in the health and strength of teeth and bones. In addition, doogh contains a low percentage of fat, which makes it a diet drink. Whey Protein Concentrate (WPC) is a product contains 25 to 89% protein and different amounts of lactose, fat and minerals. Due to the functional properties of whey protein and its nutritional value; whey protein is widely used in dairy products. The development of cross-linking bonds between protein chains by enzymes is very important today. Enzyme cross-linking of proteins can affect some of their functional properties such as solubility, water absorption, rheological and emulsifying properties. One of the most widely used enzymes in the food industry is the transglutaminase enzyme. In this study the effects of WPC in three levels (0%,1% and 2%) and the transglutaminase enzyme in two levels (0 and 1 unit per gram of milk protein) in two method of dough preparation (adding water to yogurt and fermented milk diluted with water) on rheological characteristics, and microstructure of doogh were studied. Material and MethodsRaw milk was provided by Pegah Khorasan Company, WPC from Multi Company) Mashhad (and Trans glutaminease enzyme from BDF Company of Spain. WPC was first added to milk at 45 ̊ C at three levels of zero, 1 and 2%.The milk samples were then pasteurized at 85 ̊ C for 30 min. After lowering the temperature to 45 ̊ C, the enzymatic operation was performed at two levels of zero and one unit (per gram of protein).To complete the enzyme function, the samples were incubated for 180 minutes at 45 ̊ C. Then a temperature of 90 ̊ C was applied for 1 minute to inactivate the enzyme. The samples were then cooled to 45 ̊ C. At this stage, the samples were divided into two parts. In one part of the samples; milk was diluted with water in a ratio of 6% of the total dry matter for direct production of doogh. After adding the starter, the samples were transferred to an incubator and hold at 43-42 ̊ C, until the pH reaches about 4.1.Thefermented samples were then transferred to a refrigerator. In the second part, starter was added to milk to produce yogurt; after adding starter, the mix was transferred to an incubator and hold at 43-42 ̊ C, until the pH reaches about 4.1. Doogh was produced by diluting yogurt with waterto givethe final product with 6% of total dry matter. Results and Discussion In both production methods, in samples treated only with WPC, the average particle size increased with increasing WPClevel. In both methods, the production of only enzymatically treated samples led to the formation of smaller particles with a more uniform shape and distribution. In samples of doogh produced by both production methods, WPC and transglutaminase enzyme changed the flow characteristics of doogh to non-Newtonian behavior. Samples made directly from milk had significantly higher viscosity than samples made from yogurt. In samples without enzymatic treatment, the microstructure was smooth and homogeneous with smaller particles than other samples. These particles settle very quickly. In the samples where WPC treatment was applied, the amount of large particles and non-uniformity increase with increasing WPC level. The distribution of particles in samples made directly from milk was more regular than samples made from yogurt.
Food Technology
Ghazal Shekari; Elnaz Milani; Elham Azarpazhooh
Abstract
IntroductionCeliac disease is one of the most common digestive disorder. Chicken nugget is one of the most popular instant and ready-to-eat foods, and wheat flour is one of its main coating ingredients, which contains approximately 60% gluten. Quinoa is a gluten-free grain, as a good source of dietary ...
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IntroductionCeliac disease is one of the most common digestive disorder. Chicken nugget is one of the most popular instant and ready-to-eat foods, and wheat flour is one of its main coating ingredients, which contains approximately 60% gluten. Quinoa is a gluten-free grain, as a good source of dietary fiber, has various applications in the meat products processing system as a stabilizer, fat substitute, structural components, etc. The addition of hydrocolloids also helps to improve the rheological properties of gluten-free products. The purpose of this research was to evaluate the effect of quinoa-corn mixed flour in the preparation of nugget batter as a gluten-free combination as an alternative to wheat flour, and also to investigate the effect of adding HPMC hydrocolloid on the final product characteristics. In this research, a rotatable central composite design was used to investigate the effect of two independent variables including different proportions of quinoa-corn flour (0-100, 50-50, 100-0%) and different levels of hydrocolloid (0.5-1-1.5%) on the quality characteristics of nugget. With the increase of quinoa replacement level, moisture content (0.60), batter pick up (138) and redness level 5.5 (a*) increased, and oil content (11), hardness (7.5), brightness level 41(L*), yellowness level 20(b*) decreased. The increase of HPMC also caused an increase in moisture content (0.59), brightness level (L*) of 0.39, batter pick up (137) and decrease in oil content (10) and hardness (7). Optimum conditions for the production of gluten-free nugget were determined by considering the optimal amounts for the production of high quality and healthy products, contained 90% quinoa and HPMC at a level of about 1%. Materials and Methods Corn flour was purchased from the pilot of Ferdowsi University of Mashhad. The de-saponified quinoa was prepared from Kashmir and then ground. In order to make the grains more uniform, both flours were sieved using a 30 mesh. Hydrocolloid hydroxypropyl methylcellulose was also prepared from Kian Shimi Mashhad. Oyla frying oil was used for frying the samples.The chicken nugget formulation was a mixture of 86% minced chicken, 10% onion, 1.5% garlic powder, 1% salt and 1.5% pepper. After complete mixing, these materials were poured into a freezer bag until a homogeneous and uniform mixture was obtained, and they were flatted until they reached the desired thickness (1 cm). Plastics containing chicken paste were stored in the freezer for 2 hours to facilitate cutting. Then molding was done with a circular mold with a diameter of 4 cm (Dehghan Nasiri et al., 2012).The batter formulation consisted of flour, water, baking powder, salt and hydrocolloids. In order to investigate the effect of quinoa and corn flours, and hydrocolloids, these substances were added to nugget water paste in different percentages (quinoa-corn ratio: 0-100, 50-50, 0-100 and hydrocolloids at the level of 1-1 / 5 -0.5%) and then mixed with water by mixer for 1 minute. The molded samples were first coated with flour and then immersed in the batter for 60 seconds and dripped for 30 seconds. Finally, deep frying was performed in the fryer at 170 ° C for 3.5 minutes. The fried samples were taken out of the fryer basket and the excess oil on the surface of the nuggets was removed with absorbent paper. The oil was changed after twice frying. After cooling the samples at room temperature, the tests such as moisture content, oil content, texture (hardness), color, batter pick up, peroxide and overall acceptance were performed.In this study, Design Expert 10.0.7 software and a rotatable central composite design to investigate the effect of two independent variables including different ratios of quinoa-corn flour (0-100, 50-50, 0-100%) and hydrocolloid (0.5-1-1.5%), Was used on the quality characteristics of the nugget. Finally, different models were fitted to the data obtained from the experiments and the best model was selected according to the results of analysis of variance. Results and DiscussionWith increasing quinoa replacement level, moisture content, redness (a*) and pH increased and oil content, batter pick up, texture (hardness), brightness (L*), yellowness (b*) and cooking loss decreased. Increasing the HPMC also increased the moisture content, brightness (L*), cooking loss, batter pick up, and decreased oil content and hardness. Optimum condition for production of gluten-free chicken nuggets, considering the appropriate properties was found to be 90% quinoa flour and 1% HPMC. Conclusion In general, it can be concluded that the addition of quinoa and HPMC leads to the production of high quality products with high moisture and low oil content and high nutritional value.
Food Technology
Maryam Khosravani; Seyyed Moein Nazari; Gholamhasan Asadi
Abstract
Introduction In recent years, increasing consumer awareness of the dangers of consuming high-fat products, sensitivity to proper nutritional patterns and the impact of health factors has increased consumer demand for low-fat or free-fat foods. Scientific researchers have provided a great quantity ...
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Introduction In recent years, increasing consumer awareness of the dangers of consuming high-fat products, sensitivity to proper nutritional patterns and the impact of health factors has increased consumer demand for low-fat or free-fat foods. Scientific researchers have provided a great quantity of evidence between the consumption of high-fat products and the development of diseases such as obesity, hardening of the arteries, chronic hypertension, etc. Fat removal is not an easy task because fat, in addition to nutritional aspects, affect rheological and sensory properties such as mouth feel and texture properties of the final product. Using alternative materials that can be completely or partially replaced fat in the formulation of low-fat products by imitating the properties of fat is great important. Unlike fat, which its high consumption causes many problems; fiber can play a vital role in many of the nutritional, functional, and sensory properties of food products, Some types of fiber act as fat substitutes, while producing less energy, provide a large effect of fat function properties. Increasing consumption of easy-cook meat products such as sausages induced replacement the fat content in the formulation of these products, by fat substitutes such as maltodextrin. The aim of this study was to evaluate the chemical and sensory properties of low fat German sausages produced by maltodextrin. Materials and Methods In this study, 0, 6, 12, and 18% of fat was replaced by maltodextrin in the formulation of German sausage. The chemical and sensory properties were then investigated. Chemical properties including moisture, protein, ash, and fat were accomplished according to the ISIRI standard. Evaluation of sensory properties was done by 5-point hedonic method according to Click et al. (2006). Data analysis was performed using SPSS software in a completely randomized design with a 95% confidence level. Results and Discussion The results showed that with increasing the level of maltodextrin, the amount of moisture, ash, and starch of sausage samples increased significantly. As the concentration of maltodextrin increased, the protein content of the samples decreased. The highest protein content observed in the control sample and the sample contained 6% maltodextrin and in contrary, the lowest protein content was in the sample containing 18% maltodextrin and there was no statistically significant difference between the test samples (p>0.05). Changes in maltodextrin concentrations had a significant effect on the fat content of sausage samples so that with increasing the concentration of maltodextrin in the sausage formulation, the fat content of the samples decreased (p≤0.05). Also, with increasing the percentage of maltodextrin replacement in German sausage samples, the cooking yield decreased significantly (p≤0.05). In the evaluation of sensory properties, it was found that the use of maltodextrin reduced the score in all parameters studied so that the lowest score in terms of color, texture, flavor, and total acceptance of sausage samples was related to sample with 18% maltodextrin replacement. Conclusion The vital role of the effect of dietary fiber on improving and managing the health has been proven by researchers for many years. Due to the need to reduce fat in products such as sausages, which considered as a popular meat product and based on the results observed in the present study, it is recommended to use maltodextrin fiber at the level of 6% as a fat substitute in the formulation of German sausages.
Food Technology
Rezvan Shaddel; Shadi Rajabi Moghaddam
Abstract
Introduction
Caffeine is one of the most common bioactive compounds in the world that can enhance mental and physical performance However its bitter taste has created challenges for the use of this compound in food. Nano-encapsulation technology, such as the use of liposomes, is one of the simplest ...
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Introduction
Caffeine is one of the most common bioactive compounds in the world that can enhance mental and physical performance However its bitter taste has created challenges for the use of this compound in food. Nano-encapsulation technology, such as the use of liposomes, is one of the simplest ways to overcome this issue. In this research, caffeine was encapsulated in nanoliposomes coated with chitosan and then the drink powder enriched with caffeine nanochitosome was produced.
Materials and methods
In this research, pure caffeine powder was purchased and stored in dry environment at room temperature. Ethanol (96%) and acetic acid were obtained from Mojallali Company, Tween 80 from Merck Company (Germany), lecithin (P3556), cholesterol (C8667), and chitosan (medium molecular weight) purchased from Sigma Aldrich Company (Germany). Sugar, essential oil and citric acid used in the formulation of the drink were purchased from a local store.
First, nanochitosomes in ratios of 9:1, 8:2 and 7:3 lecithin-cholesterol, were prepared using thin-layer hydration method. Then, the particle size and zeta potential were measured to determine the characteristics of the produced particles. Encapsulation efficiency was measured for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios. The stability of the chitosomal sample with a ratio of 9:1 lecithin-cholesterol was evaluated through visual observation of precipitation formation and the amount of release of encapsulated caffeine during 60 days of storage at ambient temperature was calculated. FTIR was performed for each of the components of the wall of chitosomes, caffeine powder, chitosomal solution containing caffeine and chitosomal solution without caffeine with a ratio of 9:1 lecithin-cholesterol. Nanochitosomes with 9:1 lecithin-cholesterol ratio were used in the formulation of beverages due to having the smallest particle size, favorable zeta potential, the highest microencapsulation efficiency, and high stability during storage. The drink samples were prepared in different formulations (samples containing 3 and 5% free caffeine solution, samples containing 3 and 5% chitosomal caffeine solution and the control sample). Then, the drinks were evaluated in terms of sensory characteristics and other physico-chemical characteristics (pH, acidity, Brix degree, etc.). The drinks produced were turned into powder with a freeze-dryer machine, and two important characteristics of powdered products, i.e. water solubility index and their hygroscopicity, were evaluated.
Results and Discussion
The average particle size and zeta potential for different ratios of lecithin -cholesterol were obtained in the range of 133.3-443.6 nm and +40.96 to +48.36, respectively. The encapsulation efficiency for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios were 91.2%, 86.18% and 79.09 %, respectively. The chitosomal sample with 9:1 lecithin-cholesterol ratio showed good stability during 60 days of storage at ambient temperature. FTIR results showed that caffeine was loaded in nanochitosomes. The results of the sensory evaluation of the prepared beverages showed the acceptability of the taste of the samples containing caffeine nanochitosome compared to the samples containing free caffeine, which indicates the success of chitosomal nanocarriers in covering the bitter taste of caffeine. The results of measuring the color of different drink samples showed that there is no significant difference between the color of samples. The results of measuring pH and acidity did not show significant differences between different drink samples. The results of measuring the solubility of different drink powder samples showed that the samples containing caffeine nanochitosomes have low solubility compared to other drink powder samples. Also, the hygroscopic amount of the drink powder containing caffeine nanochitosomes was lower than the other samples, which is considered as an advantage for powdered products.
The results obtained in this research showed that nanochitosomes are an efficient system in covering the bitter taste of caffeine. Therefore, with the production of caffeine nanochitosomes and its usage in the formulation of powder drinks, it is possible to produce energizing and desirable drinks without the need to use high amounts of sucrose.
Food Technology
Yazdan Moradi; Mansoreh Ghaeni; Haleh Hadaegh
Abstract
Introduction
Seaweeds contain a high amount of protein, essential amino acids, vitamins, minerals, unsaturated fatty acids such as arachidonic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), natural pigments, macro and micro nutrient compounds. Microalgae Spirulina (Spirulina ...
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Introduction
Seaweeds contain a high amount of protein, essential amino acids, vitamins, minerals, unsaturated fatty acids such as arachidonic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), natural pigments, macro and micro nutrient compounds. Microalgae Spirulina (Spirulina platensis) is a species with high nutritional value. About 60% to 70% of the dry weight (Spirulina platensis) is protein, which has all the essential amino acids. This is a cyanobacterial microalga that is cultivated all over the world and used as a supplement in the human diet in the form of tablets, powder and cookies, bread, salad and soup. Several studies have been conducted in the field of investigating the effect of microalgae addition in food products. The purpose of the current research was to investigate the effect of this microalgae powder on sensory, physical, protein and iron properties of three different products of bulk bread, cake and layered sweets with different formulations.
Materials and Methods
Spirulina microalgae dry powder in 0.25%, 0.5%, 0.75%, 1% and 1.25% was added to the formula of three products: bulk bread, layered pastry, and cake. From each product, a sample without microalgae powder was also prepared and considered as a control. The treatments were evaluated in terms of sensory, color, texture, protein and iron content. Sensory evaluation was carried out by 30 panelists using 7 hedonic points to evaluate the color, flavor, texture, smell and overall acceptance. The color of the surface of the samples was done with a Minolta Chroma Meter (CR-300 Minolta Japan). The results calculated based on L* (whiteness/darkness), a*(redness/greenness) and b*(blueness/yellowness). Hardness of samples was measured with Texture Analyzer TA-XT2 (Stable Micro Systems, Surrey, England) and P/0.5 cylindrical probe (12.5 mm diameter) with 30 kg load cell. Protein of the samples was measured by Kjeldahl method and the amount of iron was measured according to the standard method of AOAC 999.11. All analyses were performed in three repetitions and one-way ANOVA and Tukey's test were used to compare the means.
Results and Discussion
The results showed that the behavior of spirulina microalgae in changing the characteristics of the three products is different, and this difference is especially significant in sensory characteristics. The addition of spirulina microalgae increased the amount of protein and iron in different treatments. This increase for protein in bread, cake and sweets was about 1, 0.6 and 1.2 percent, respectively. Also, the amount of iron in treatments containing microalgae in bread, cake, and layered sweets was 4, 5, and 3 mg/kg, respectively. Spirulina microalgae is basically known as an aquatic plant with high protein and iron. The microalgae used in this research contained a high amount of protein (67.97%) and 29.5 mg/100 grams of iron, so adding this microalga to the samples increased the amount of protein and iron. Sensory evaluation of the samples showed that all three products had an acceptable acceptance score. However, in comparison among the three products of bread, cake and layered sweets, bread had a lower score than the other two products. The instrumental analysis of L*, a*, b* color indices showed that the increase of spirulina caused green color in the treatments and this color change is more significant in the bread sample. Also, the results of texture analysis showed that the addition of spirulina reduces the hardness of samples containing spirulina. It can be concluded that spirulina microalgae can be used to improve texture, color, and also increase the amount of protein and iron in products.
Food Technology
Bahareh Nowruzi
Abstract
Introduction
Intelligent food packaging as a new technology can maintain the quality and safety of food during its shelf life. This technology uses indicators and sensors that are used in packaging and detects physiological changes in food (due to microbial and chemical degradation). These indicators ...
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Introduction
Intelligent food packaging as a new technology can maintain the quality and safety of food during its shelf life. This technology uses indicators and sensors that are used in packaging and detects physiological changes in food (due to microbial and chemical degradation). These indicators usually provide information that can be easily identified by the food distributor and the consumer. However, most of the markers currently used are non-renewable and non-degradable synthetic materials. Microalgae that live in both marine and freshwater are a versatile solution for building new biosensors to detect pollutants such as herbicides or heavy metals. These photosynthetic microorganisms are very sensitive to their environmental changes and allow the detection of pollutants. In the past few years, several studies have been conducted in relation to the development, evaluation and application of biosensors using natural compounds in smart food packaging, and some of them are reported and summarized in Table 2.
Materials and Methods
In these studies, examples are mainly focused on biosensors related to biopolymers, but some other synthetic polymers that are easily degraded have also been used as examples. In Table 2, it is also specified what the function and application of the sensor is and how it reacts to the loss of freshness of food. Most sensors are sensitive to the change in pH caused by the release of volatile nitrogen compounds, and this change is characterized by a colorimetric response. Sensors are usually placed in the space above the food container, avoiding direct contact with the food, but close enough to detect changes in the environment and respond to changes in food quality. When these biosensors are integrated with biopolymers, they are usually incorporated into the polymer structure, and the color change of the layers (film) indicates changes in food quality in the packed product. The collected information also clearly shows that extracts rich in chemical compounds of pigments that change color with pH and especially anthocyanins have been used in these biosensors. In addition, most studies of biosensors have been conducted on fish, meat, and seafood, which is probably because their quality degradation is an important economic loss and also because the pH of the surrounding environment is changed during the degradation process. , and this change is easily detected through pH-sensitive biosensors. Smart food packaging technology has made it possible to monitor food quality by incorporating markers, sensors and radio frequency identification (RFID) into packaging. The technology also allows producers and consumers to trace the history of a product through important points in the food supply chain.Interestingly, some compounds applied and tested in the sensor not only provide a pH-sensitive dye, but also have other bioactive properties, for example, antimicrobial properties, and its presence in the polymer matrix can also increase the storage activity of packaging materials.
Results and Discussion
This paper shows that microalgae can be used as biosensors to detect pollutants such as herbicides, heavy metals and volatile organic compounds. These biosensors are very sensitive and reproducible for physical or chemical analysis. One of the main advantages of these microalgal biosensors is that repeated measurements can be performed without extensive sample preparation. They can also be selective, for example chlorophyll fluorescence emitted from photosynthetic activity allows the detection of herbicides, while inhibition of alkaline phosphatase and esterase allows the determination of heavy metals and organophosphate insecticides. Recently, great progress has been made in the identification of genes and related pathways in microalgae, and powerful techniques for genetic engineering have been developed. Collectively, the progress achieved in these areas will rapidly increase our ability to genetically optimize the production of more sensitive microalgae-based biosensors.
Food Technology
Massoumeh Mehraban Sangatash; Maryam Dadras-Moghadam; Seyed Ali Mortazavi; Hanieh Yarabbi
Abstract
The increasing growth of cardiovascular diseases, high blood pressure, and hardening of the vessel walls as well as obesity in many countries has made low-fat and low sodium pizza cheese one of the subjects of study all over the world. The effects of four important independent variables including inulin ...
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The increasing growth of cardiovascular diseases, high blood pressure, and hardening of the vessel walls as well as obesity in many countries has made low-fat and low sodium pizza cheese one of the subjects of study all over the world. The effects of four important independent variables including inulin (0-0.025 %), pre-gelatinized starch (0-0.5 %), NaCl (0.35-1%), and KCl (0.35-1%) were studied. The fat content of imitation pizza cheese was significantly decreased to 11.91% with the increased levels of inulin and starch substitution (p<0.05). Also, its moisture and pH values were significantly different (p < 0.05). The increased levels of pre-gelatinized starch and inulin reduced hardness (from 5.04 to 3.55) and adhesiveness (from 4368.89% to 1640.54%), however, increased cohesiveness (from 0.365 to 0.43) and springiness (from 0.456 to 0.545). NaCl and KCl increased the hardness of the product. Inulin and starch led to decrease the a* value. The b* value decreases with the increase of inulin and increases with the increase of modified starch. The formulation containing 0.19% inulin, 0.4% pre-gelatinized starch, 0.35% NaCl, and 0.50% KCl was found as the optimal formulation for low-fat imitation cheese. Results of scanning electron microscope (SEM) images revealed that inulin crystals were accumulated in the continuous phase, which this can lead to important changes in the sensory and textural properties. The study concludes that inulin or starch can be used to replace up to 3.6% of fat in the imitation pizza cheese and 0.35% NaCl-0.50% KCl to lower the sodium content of the product.
Food Technology
Fayza Hussein Alhasan; Mostafa Mazaheri Tehrani; Mehdi Varidi
Abstract
Preparing air-in-oil-in-water (A/O/W) double emulsion involves two key steps: oleofoam formation and dispersion of the oleofoam in an aqueous solution containing protein as an emulsifier and hydrocolloid as a thickening agent. This study aimed to investigate the effect of oleofoam level and varying concentrations ...
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Preparing air-in-oil-in-water (A/O/W) double emulsion involves two key steps: oleofoam formation and dispersion of the oleofoam in an aqueous solution containing protein as an emulsifier and hydrocolloid as a thickening agent. This study aimed to investigate the effect of oleofoam level and varying concentrations of protein-polysaccharide ratios on the thermal stability, encapsulation yield and rheological properties of A/O/W double emulsion. An oleofoam was obtained using a lipophilic emulsifier (distilled monoglyceride MG) and sunflower oil at 5°C with maximum stability. Two levels of oleofoam (20% and 25 wt %) were added to an aqueous solution containing different concentrations of sodium caseinate (SC) (5, 8, and 10 wt %) and kappa carrageenan (KC) (0.4 and 0.8 wt %). Results indicate that oleofoam level did not significantly affect air encapsulation efficiency and particle size, while protein-polysaccharide ratios could significantly impact all properties of A/O/W double emulsion. Increasing the concentration of sodium caseinate and kappa carrageenan improved thermal stability and encapsulation yield while simultaneously reducing particle size. All A/O/W emulsions exhibited shear thinning behavior among the range of shear rates studied, indicating significant potential for food applications.
Food Technology
Zeinab Mohkami; Hasan Ghorbani Ghouzhdi; Fateme Bidarnamani; Yasub Shiri
Abstract
Introduction Yogurt is one of the most widely consumed fermented milk products, which, like any other dairy products, is prone to spoilage and poor quality. On the other hand consumers have become more cautious about their diet and health. Their is an increasing demand for food products with higher ...
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Introduction Yogurt is one of the most widely consumed fermented milk products, which, like any other dairy products, is prone to spoilage and poor quality. On the other hand consumers have become more cautious about their diet and health. Their is an increasing demand for food products with higher nutritional values and health benefits. The continuous improvement of the production process and the quality of yogurt is at the heart of manufacturers’ concerns. Also, finding a safe, cheap and affordable solution that, in addition to controlling blood sugar and preventing the complications of diabetes, relieves the pain of diabetic patients; has always been of interest to researchers. The medicinal plant Bitter gourd (Momordica charantia L.) from the cucurbitaceae family is used in traditional medicine to control blood sugar. Carla fruit is a rich source of phytochemical compounds such as proteins, steroids, alkaloids, mineral compounds, lipids, triterpenoids and polyphenols. Functional yogurt is one of the dairy products that can contain bioactive compounds in order to increase its acceptability and improve its nutritional and medicinal properties. Therefore, this study was carried out with the aim of producing colored yogurt containing Carla fruit powder in order to increase the variety of appearance, marketability of the product and improve the nutritional characteristics of yogurt with emphasis on the consumption of novel product. Materials and Methods In this study, the effects of adding Carla powder to yogurt were investigated with the aim of producing a beneficial food for diabetics. Carla fruit was collected from the medicinal plants collection of the Agriculture Institute, Research Institute of Zabol, Zabol, Iran. Then it was washed with water and cut into thin layers. These parts were completely dried in an electric oven at 40 ºC for 48 hours and pulverized with an electric mill. Carla fruit powder was added to the samples in four levels of 0 (control), 0.2, 0.4 and 0.6%. Physicochemical properties of samples such as pH, acidity, viscosity (using Brookfield spindle viscometer) and water holding capacity were measured. Total phenol content was measured by Folin Ciocalteu reagent method. Antioxidant properties were investigated by scavenging rate of DPPH free radicals. The results were analyzed by SPSS version 21 statistical software at the probability level of 5% (P˂ 0.05). Duncan's multiple range test was performed to determine the statistically significant difference between the means. Results and Discussion The results of this study showed that the highest pH (4.17) was detected in the control and the addition of Carla fruit powder led to a decrease in pH. Storage time also lower the pH in yogurt samples. The highest acidity (1.3%) was measured in the treatment containing 0.6% Carla fruit powder and the lowest (0.59%) was in the control. It means that adding Carla powder to yogurt leads to an increase in acidity. The highest amount of phenolic compounds (475.63 μg equivalent of gallic acid/ml yogurt), was calculated in a sample containing 0.6% of Carla fruit powder. However, extended storage time, decreases the amount of phenolic compounds. By increasing the percentage of Carla fruit powder in yogurt samples, the amount of antioxidant activity increased. So that the highest antioxidant activity (93%) was related to the treatment containing 0.6% Carla powder on the 28th day of the storage. In the present study, the highest percentage of water holding capacity (84%) was observed in samples containing 0.6% Carla powder. The lowest water holding capacity (57.61%) was measured in the control sample at the first day of storage. Conclusion According to the results of this study, adding Carla powder to yogurt at the level of 0.6%, in addition to maintaining appearance properties, can increase its physicochemical properties and produce a novel food. In general, Carla powder can play a significant role in improving the textural properties of yogurt, and by increasing the viscosity and the water holding capacity, can reduce the negative effects of the storage period. Acknowledgement This research was conducted with the financial support by Research Institute of Zabol (Grant code: IR-RIOZ-GR-9027).
Food Technology
S. Mostafa Sadeghi; Mandana Tayefe; Leili Fadayi Eshkiki; Kambiz Ghiasvand
Abstract
IntroductionBakery products such as cakes are consumed in a relatively large amount all over the world due to their ready to eat format. Among different foods, bakery products provide a great opportunity to use edible portions of seeds, vegetables or other unconventional food sources. On the other hand, ...
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IntroductionBakery products such as cakes are consumed in a relatively large amount all over the world due to their ready to eat format. Among different foods, bakery products provide a great opportunity to use edible portions of seeds, vegetables or other unconventional food sources. On the other hand, cakes are susceptible to oxidation due to high amounts of fat and consequently reduce shelf life. Therefore, due to the high nutritional value of cake, improving its characteristics seems necessary. Wheat germ is the richest known source of vitamin E of plant origin. Consumption of wheat germ can prevent artery- clogging and also helps fight against free radical damage and procrastination are effective in the aging process of cells and preventing coronary disease. Despite the beneficial properties of wheat germ, it is difficult to keep it raw in the formulation of crops due to the presence of high unsaturated fatty acids and lipase enzymes. However, by performing thermal processes such as steam, fluidized substrate or thermal dryer, enzymes such as lipase and lipoxygenase can be deactivated. In this study, the effect of adding wheat germ as a rich source of fiber, tocopherols and essential fatty acids as well as ascorbyl palmitate as antioxidant compound on the qualitative and structural properties of cake was investigated. Materials and MethodsIn this study, five treatments of oil cake including control, ascorbyl palmitate (100 ppm), wheat germ (5, 10 and 15%), were prepared and physic-chemical properties including the moisture, firmness and volume of cake at the beginning of storage period, peroxide number and acidity during 14-day storage period were investigated. In order to evaluate the texture of the cake, texture analyzer was performed with dimensions of 25 mm and penetration of 50% in the sample at a speed of 2 mm/s and a 30-second stop between the first and second compressions. The specific volume of the produced samples and moisture of the middle part of the samples were measured 3 hours after baking. Results and DiscussionThe results showed that addition of L-ascorbyl palmitate had no significant effect on moisture content, hardness and cake volume. However, wheat germ increased hardness (in amounts more than 5%), decreased moisture content and specific volume of cake. Also, with increasing the amount of wheat germ, a significant decrease in peroxide and acidity of the samples were observed during the storage period. However, the values of the mentioned indices in the sample containing palmitate ascorbyl were lower than those containing wheat germ. According to the results, it seems that the sample containing 5% processed wheat germ can be recommended as a suitable formulation for cake enrichment. ConclusionConsidering that oxidation of cakes and reduction shelf life in different type of cakes are probable due to the presence of considerable amounts of fatty acids, in this study the effect of adding L-ascorbyl palmitate as a common antioxidant and processed wheat germ due to its antioxidant behavior on the moisture content, hardness, specific volume, texture and shelf-life characteristics of the oil cake was investigated. The overall results show that by adding L-ascorbyl palmitate, there was no significant effect on moisture content, hardness and specific volume. However, processed wheat germ increased hardness (in amounts more than 5%), decreased moisture content and specific volume of cake. Also, with increasing the amount of wheat germ, a significant decrease in peroxide value and acidity of the cake was observed during the storage period. However, the values of moisture content, hardness and specific volume in the sample containing palmitate ascorbyl were lower than samples containing wheat germ. According to the results, it seems that sample containing 5% processed wheat germ can be recommended as a suitable formulation for cake enrichment and artificial antioxidant replacement.
Food Technology
Parisa Dianat; Mahdi Haji Abdolrasouli; Morteza Yousefzadi
Abstract
Introduction Consumer demand for healthy food free of chemical preservatives and environmental concerns with plastic packaging environments are analyzed, which can be replaced by aquatic environments that can be contaminated, for the development of bio-based packaging materials. Natural polymers ...
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Introduction Consumer demand for healthy food free of chemical preservatives and environmental concerns with plastic packaging environments are analyzed, which can be replaced by aquatic environments that can be contaminated, for the development of bio-based packaging materials. Natural polymers have the ability to be biodegradable due to the presence of oxygen or nitrogen atoms in their main polymer chain compared to the dominant carbon-carbon bonds in fossil-based polymers. Among the various biopolymers used to prepare multilayer films, polysaccharides are considered as the main components of the film due to their abundance and non-toxicity. These films generally have good mechanical strength, moderate physical properties, and most importantly, are edible and easily degradable. However, they are very brittle and hydrophilic, and these properties are undesirable in food packaging applications. Among polysaccharides, agar, commercially extracted from seaweed, is one of the most common and widely studied base materials. Agar is insoluble in cold water, but soluble in water at 90-100°C. When making an agar film, the solution and casting surface must be kept above the agarose gel setting temperature to avoid premature gelation. Compared to other biopolymers, agar is more stable at low pH and high temperature. This thermoplastic and biocompatible polysaccharide creates films with high mechanical strength, transparency and moderate barrier properties to carbon dioxide and oxygen, and most importantly, it is edible and easily biodegradable. Mixing agar with other polymers such as polyvinyl alcohol (PVA) and polyethylene improves the mechanical, thermal and biodegradability properties of bio composites. The main goal of this study is to make biofilms for use in packaging industries with agar polymer extracted from macroalgae species Acanthophora sp. Agar was extracted by sodium hydroxide/heating method and the film was prepared in combination with industrial polymer PVA and glycerol. Materials and Methods To make biofilms based on agar polymer, firstly, optimization of agar polymer extraction from macroalgae species Acanthophora sp. was done by sodium hydroxide/heating method, and in the next step, total phenolic compounds and the amount of soluble protein in extracted agar were measured. In the next step, glycerol with 30% by weight was used as a softener and PVA polymer with a weight ratio of 25% to the dry weight of agar powder was used to make bio composite by solvent casting method, in order to strengthen the mechanical and physical properties of bio composites. Characterization tests of the prepared composites included: XRD, FTIR and Tensile test. Laboratory tests include; The percentage of solubility in water and degree of swelling for all bio-composites were evaluated to determine the optimal physical properties of bio-films. Results and Discussion:he results showed that; 15% extraction efficiency was obtained for sodium hydroxide/heating pretreatment method. The results of measuring the amount of total phenolic compounds in agar solution extracted by sodium hydroxide/heating method showed that the number of phenolic compounds in agar solution was 0.077 ± 0.004 in terms of mg of gallic acid/g of agar. The results of measuring the amount of protein in extracted agar determined by Bradford method showed that the agar solution contains 0.040 ± 0.019 mg/ml of protein. A decrease in the swelling rate and an increase in the water solubility of the agar bio composite occurred with the addition of glycerol and PVA polymer. The results of the tensile test showed that the addition of glycerol, a small hydrophilic molecule, to the agar bio composite leads to a decrease in the elastic modulus and an increase in flexibility. Adding PVA to agar/glycerol biofilm caused a decrease in the amount of elastic modulus and percentage of flexibility, which is the main factor of this phenomenon, the low values of elastic modulus and flexibility of PVA. Finally, the results confirm the use of these coatings for packing fruits and vegetables in tropical regions by increasing their shelf life for at least 5 days at 25°C.
Food Technology
Reza Safari; Soheil Reyhani Poul
Abstract
Introduction Phycocyanin is one of the pigments used in the food industry due to its antioxidant and antibacterial as well as coloring properties. This pigment is commercially produced from Spirulina platensis microalgae, in the form of photoautotrophic cultures and in open environments in large ...
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Introduction Phycocyanin is one of the pigments used in the food industry due to its antioxidant and antibacterial as well as coloring properties. This pigment is commercially produced from Spirulina platensis microalgae, in the form of photoautotrophic cultures and in open environments in large ponds or pools in tropical or subtropical areas at the edges of oceans. Different techniques are used in order to extract phycocyanin from spirulina microalgae.. Each technique has its own advantages and disadvantages besides different efficiency. These methods include freezing-defrosting, enzymatic, ultrasound, high hydrostatic pressure, ultracentrifuge, ultra homogenization, extraction using water and various solvents. Of course recently, the production of recombinant phycocyanin has been considered as a suitable option for the production of heterotrophic phycocyanin. The purpose of the current research was to cultivate Spirulina platensis, evaluation of the microalgae growth process, and comparison of the efficiency of different methods in the extraction of phycocyanin pigment. Materials and Methods The pure sample of Spirulina platensis microalgae was prepared from Algaeology Laboratory, Biology Department of Tarbiat Modares University. For the cultivation of spirulina, Zarrouk culture medium with different compositions was used, and after cultivation in smaller scales (100 and 500 ml), the final cultivation was carried out in volumes of 5 and 50 liters. After cultivating the microalgae and exposing them to fluorescent light with appropriate light lux intensity (3500 to 8000) and a period of 12 hours of darkness and 12 hours of light, the samples were placed at 29 °C for 16 days. In order to evaluate the growth process of the algal mass, the absorbance of the solution containing the algal cells was read at a wavelength of 540 nm. After preparing the dry mass of spirulina microalgae, four methods of ultrasound, freezing-defrosting, enzymatic and mineral solvent technique were used to extract phycocyanin. In the next steps, the efficiency of each method was evaluated by measuring the concentration and purity of phycocyanin. In addition, the effect of applying the purification process by ammonium sulfate on the concentration and purity of the extracted pigment was also evaluated. This research was conducted in a completely randomized design and SPSS and EXCEL softwares were used for statistical analysis and drawing of diagram, respectively. Data were analyzed using one-way analysis of variance and the difference between the means was evaluated by Duncan's test at 95% confidence level. Results and Discussion The results showed that microalgae growth from day 0 to 14 had an upward trend and the resulting changes were significant at all times, except days 14 and 16 (p<0.05). Also, after passing the short resting phase (2 days), the microalgae entered the logarithmic growth phase and continued to grow until the 14th day, but between the 14th and 16th days, the growth was almost constant. In the following, it was found that the mass produced after 16 days is 1120 mg/l. The concentration of phycocyanin extracted in enzymatic and ultrasound methods (1.815 and 1.786 mg/ml, respectively) had no significant difference (p>0.05) and was at a higher level than the other two methods (p<0.05); In addition, the pigment concentration was higher in the freezing-defrosting technique (1.535 mg/ml) than in the mineral solvent method (1.121 mg/ml). After purification of the pigment using ammonium sulfate, the pigment concentration and purity increased significantly in each method (p<0.05). The results of this research showed that by choosing the optimal method and applying the purification process using ammonium sulfate, the extraction efficiency of phycocyanin from Spirulina microalgae (Spirulina platensis) could be increased. Conclusion Based on the results of this research, the growth trend of Spirulina platensis in Zarrouk culture medium was ascending first and then constant (during 16 days). Ultrasound technique and enzymatic method (lysozyme enzyme) to extract phycocyanin pigment from Spirulina platensis microalgae have more efficiency than freezing-defrosting and inorganic solvent (hydrochloric acid) methods. Also, purification of the extracted pigment using 40% ammonium sulfate increases the concentration and purity of phycocyanin in each method.
Food Technology
Ali Hosseini; Nafiseh Zamindar; Yasaman Esmaeili
Abstract
IntroductionToday, carrots are widely used in freshly cut products, including ready to eat salads, however, its shelf life is reduced due to the damage caused on the texture of the product which accelerate the reduction of nutritional value as well as the growth of microorganisms, (Azizian et al., 2020). ...
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IntroductionToday, carrots are widely used in freshly cut products, including ready to eat salads, however, its shelf life is reduced due to the damage caused on the texture of the product which accelerate the reduction of nutritional value as well as the growth of microorganisms, (Azizian et al., 2020). To increase the shelf life of freshly cut products, it is recommended to use coatings on the surface of these products. Alginate is a hydrophilic biopolymer and having unique colloidal characteristics, it demonstrates a suitable coating function. Olivas et al. (2008) showed that by coating fresh apple slices with alginate and antimicrobial agents increased the shelf life of apple and decreased weight loss. Among the native plants of Iran, we can mention the Oliveria plant, which belongs to the Amblifra family. The aerial parts of this plant have a significant amount of essential oils (EOs). Researches by Amin et al. (2005) on the antimicrobial properties of Oliveria essential oils have shown a broad-spectrum antimicrobial activity against all studied organisms, and this effect is comparable to that of commercial antibiotics. Packaging with modified atmosphere is one of the best ways to increase the shelf life of fruits and vegetables. The purpose of this study was to investigate the effect of alginate and Oliveria essential oils on the physicochemical and microbial characteristics of grated carrots in polypropylene packages with modified atmosphere during storage. MethodsEssential oil of Oliveria plant was extracted, dehydrated by sodium sulfate and placed in sealed glass container and stored at 4˚C until using. Carrots prepared from Wilmoren cultivar. An industrial crusher crushed the carrots, and samples were coated by treatment solutions. Two treatments of coating were prepared, one as control with 0% and the other one with 1.5% alginate with stirring and moderate heat (50-60°C) (Lu et al., 2009). Then the Oliveria EO was added to the alginate solution at the specified concentration. The resulting solution was deaerated at 25˚C.T1: control sample (without coating)T2: 1.5% alginateT3: 150 ppm Olivieria EOT4: 250 ppm Olivieria EOT5: 1.5% alginate and 150 ppm of Olivieria EOT6: 1.5% alginate and 250 ppm of Olivieria EOAfter weighing (250 g), the grated carrots (control and coated) were placed in 10 g polypropylene packages of suitable food grade in dimensions of 50 × 190 × 144 cm and the package was injected with 5% O2, 5% CO2 and 90% N2. The packages were then stored in the refrigerator for 12 days at 4±1˚C. All experiments were performed on days 1, 3, 6, 9, and 12. Evaluation of Chemical, Microbial and Sensory CharacteristicsA pH meter used for pH determination (Rad et al., 2020). The acidity measured based on Rocha et al. (2007) method.The weight was reported using pre and post-storage weight. The carotenoid concentration calculated by Rocha et al. (2007) method. Total soluble solids determined by refractometer (Rad et al., 2020). Ascorbic acid content measured by Falahi et al. (2013) method. The L*, a*, b* and WI (white index) indicators of grated carrots evaluated by Hunter lab system. A 5-point hedonic test was used to assess sensory attributes(Ajnevardi et al., 2002). The internal gas concentration evaluated by Ullsten & Hedenqvist (2003) method. Total count microorganisms, mold, and yeast were counted according to the method of Azizian et al. (2020). Data AnalysisThis study was conducted in a completely randomized design with factorial form to investigate the effect of independent variables of type of alginate coating (2 levels), essential oil (3 levels) and time (5 levels) on the physicochemical properties of grated carrots (3 replications) and total counting, mold and yeast (2 replications). Mean comparison was performed using LSD test at 5% probability level and SPSS software was used to statistically analyze data. ResultThe results showed that the level of acidity, carotenoid and acid ascorbic, the amount of L* and sensory (color, quality, flavor, odor) scores reduced during time. By contrast the level of pH, weight loss, the amount of a*, b*, CO2, TSS and total counts increased (P<0.05). Also, with increasing the concentration of essential oils and alginates, the amount of acidity, carotenoids, ascorbic acid, L* increased and pH, weight loss, TSS, a*, b*, CO2 and total count decreased (P<0.05). Escherichia coli, mold and yeast count of the samples did not show any growth from the mentioned treatments until the 12th day. Overall, the Oliveria essential oil and alginate were effective in improving the properties of grated carrots under the modified atmosphere during storage. ConclusionThe study showed that Oliveria EO and alginate added to grated carrots in modified atmosphere packaging during storage was effective in reducing respiration, water loss, microbial load and increased the shelf life. Treatment containing 1.5% alginate and 250 ppm Oliveria EO showed the best chemical, microbial and sensory characteristics. The results indicated that by packing under modified atmosphere and coating by alginate and Oliveria EO, a new carrot product provided to the market with maintaining durability and quality characteristics during storage.
Food Technology
Elham Safaei; Hannan Lashkari; Sara Ansari; Alireza Shirazinejad
Abstract
Introduction Manufacturers are trying to replace plastic materials in the food packaging industry with biodegradable and edible films. Biodegradable edible films and coatings are mainly made from carbohydrates, lipids and proteins and their mixtures. In recent decades, various carbohydrates from ...
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Introduction Manufacturers are trying to replace plastic materials in the food packaging industry with biodegradable and edible films. Biodegradable edible films and coatings are mainly made from carbohydrates, lipids and proteins and their mixtures. In recent decades, various carbohydrates from plant sources have been investigated and introduced as new compounds for the preparation of these films. Flaxseed gum is a white to cream-colored powder that dissolves in water and produces a gel, and is a desirable compound for forming films and coatings. Recently, through the integration of reinforcements or fillers with at least one nanometer dimension in the substrate of one or more natural biopolymers, the physicochemical, mechanical, optical, thermal and barrier properties of pure biofilms have been improved. The use of cellulose nanoparticles in biofilms as a reinforcing agent for polymer materials leads to the creation of composite films with better quality characteristics and leads to the creation of functionalization activities in film production. Therefore, the aim of this research was to produce and characterize edible and biodegradable film based on the combination of flaxseed gum and cellulose nanocrystals. Materials and Methods Cellulose nanocrystals (Degree of crystallinity: 42% and average particle size: 58 nm) were extracted from cotton linters. Glycerol and other chemicals used for this research were obtained from Merck, Germany. Flaxseeds were purchased from the local market of Shiraz (Iran). Bionanocomposite films were prepared from different ratios (0:100, 30:70, 50:50, 70:30 and 100:0) of flaxseed mucilage (2% w/v) and cellulose nanocrystal (6% w/v) solutions. The prepared solutions were poured on a petri dish with a diameter of 15 cm and dried in an oven at 80°C for 4 hours. Their physical, color and mechanical properties were investigated and the best ratio was selected for the preparation of bionanocomposite film. The produced films were subjected to different analysis to determine thickness, solubility, water absorption capacity, permeability to water vapor, tensile strength, elongation at break point, and colorimetry. The microstructure of the produced film was studied using a scanning electron microscopy (SEM).The average data were analyzed by analysis of variance in a completely randomized design using SPSS 22.0 software. Differences between treatments were expressed in Duncan's multiple range test at the 95% probability level (p<0.05) and the corresponding graphs were drawn with Excel 2013. Results and Discussion The results of the film thickness test showed that the film containing 100% mucilage has the lowest thickness and with the addition of cellulose nanocrystals, the thickness increased significantly (p<0.05). The results of the water solubility and water absorption capacity of the film samples showed that the addition of cellulose nanocrystals to the flaxseed mucilage film initially led to a significant decrease in the water solubility and water absorption capacity (p<0.05), so that the lowest level ofthese two physical parameters were obtained in the film containing the combination of 70% flaxseed mucilage and 30% cellulose nanocrystal, and then with the increase of cellulose nanocrystals, an increase in water solubility and water absorption capacity of the films was observed. Nanocrystal cellulose at low levels (30%) acted as a filler and was uniformly dispersed in the network of the film and by filling the empty pores of the biopolymer film based on flaxseed mucilage, it caused the transfer of water vapor more complicated and reduced the permeability to water vapor. However, its higher amount increased the permeability of the film to water vapor.The results showed that by adding cellulose nanocrystal to the film based on flaxseed mucilage and increasing its amount, the brightness of the films decreased and the intensity of redness, yellowness and turbidity of the films increased significantly (p<0.05). By combining flaxseed mucilage and cellulose nanocrystals in a ratio of 30:70, the best film was produced in terms of mechanical strength and stability against moisture and water vapor. The SEM image of this film showed a smooth, even surface and a uniform distribution of cellulose nanocrystals in the film network. Conclusion The results finally showed that the combination of flaxseed mucilage and cellulose nanocrystals in a ratio of 30:70 was able to produce a biodegradable and edible film with favorable structural and barrier properties. The characteristics of this film include; thickness (0.313mm), solubility (53.42%), water absorption capacity (44.44%), permeability to water vapor (0.350 g.m-1s-1Pa-1 × 10 -10), tensile strength (0.973 MPa), elongation at break point (30.52%) were obtained. The colorimetric indices L*, a*, b* and turbidity were determined as 79.73, 1.95, 3.48 and 1.335 mm-1 respectively. Acknowledgement The authors would like to express their sincere gratitude to Islamic Azad University, Sarvestan Branch.
Food Technology
Parisa Parsa; Mostafa Mazaheri Tehrani; Mohebbat Mohebbi
Abstract
Introduction Bran-enriched bread is a source of dietary fibers and other nutritional compounds; However, wheat bran also contains phytic acid, asparagine, a high ratio of insoluble to soluble fiber, insoluble arabinoxylans, and glutathione that cause nutritional and technological problems in the ...
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Introduction Bran-enriched bread is a source of dietary fibers and other nutritional compounds; However, wheat bran also contains phytic acid, asparagine, a high ratio of insoluble to soluble fiber, insoluble arabinoxylans, and glutathione that cause nutritional and technological problems in the product. Therefore, to produce bran-enriched bread, it is necessary to use pre-processed wheat bran. Despite the modifications made in wheat bran to improve its nutritional and functional properties, wheat bran-rich cereal products have a dark color, rough texture, and small loaf volume. To improve the quality of bran-enriched bread, common additives in the bakery industry such as enzymes, alcoholic sugars, emulsifiers can be used. Xylanase is one of the important classes of hemicellulase enzymes that delays the aggregation of amylose chains, and consequently, bread staling. Moreover, the xylanase enzyme increases the loaf volume by converting water-insoluble arabinoxylans into soluble ones. SSL emulsifier can interact with gliadin protein and prevent its participation in crosslinking bonds, which softens the bread crumbs. Polyols can reduce water activity and improve the softness of bread. Sorbitol is commonly used in starch-based foods to improve their quality by modifying starch gelatinization and retrogradation. So far, no article has been presented on the simultaneous effect of enzyme, alcoholic sugar, and emulsifier improvers on bread enriched with processed wheat bran. In addition, the amount and composition of improvers used in combination with each other can cause various effects on different properties of bread. This study aims to improve the technological, physicochemical, and finally stalling of optimal bread enriched with 15% of pre-processed wheat bran while benefiting from the nutritional properties of wheat bran. Materials and Methods In this study, the effect of sodium stearoyl-2-lactylate emulsifier (0-0.8%), xylanase enzyme (0-0.05%), and sorbitol sugar alcohol (0-6%) as improving agents on The physicochemical and technological parameters of bread enriched with 15% pre-processed wheat bran were investigated based on the response surface method in the form of a rotatable central composite design. After that, design-expert software determined the optimum percentage of improvers to achieve the minimum amount of firmness and cohesiveness of bread and the maximum amount of specific volume, moisture of bread crumbs, lightness of bread crust, and solidity of bread pore structure. Finally, optimal and control samples were compared using the Differential Scanning Calorimetry and Scanning Electron Microscopic experiments. Results and Discussion The experiments showed the bread's firmness under the influence of SSL emulsifier and sorbitol alcoholic sugar and chewiness, by adding SSL emulsifier and xylanase enzyme decreased significantly. All three improvers caused a significant increase in the specific volume of bread. The pore characteristics of bread crumbs, such as solidity and circularity, were significantly improved by adding an SSL emulsifier, and roundness was considerably enhanced by adding sorbitol alcohol. The brightness of bread crust was also increased significantly by the SSL emulsifier and xylanase enzyme. In addition, the Xylanase enzyme improved the moisture content of bread by substantially increasing the moisture content of bread crumbs, and alcoholic sugar and SSL emulsifier with a significant reduction in crust moisture. Moreover, the chewiness of bread on the first day after baking, specific volume, moisture of bread crust on the third day after baking, and the solidity of bread crumbs were significantly improved due to the interaction of SSL emulsifier and sorbitol alcohol. Also, the interaction of the xylanase enzyme and SSL emulsifier improved the specific volume, moisture of the bread crumbs on the first day after baking, the lightness of the bread crust, the pore area fraction, and the circularity of the bread crumbs. Finally, the optimal formula was obtained, including 0.563% of SSL emulsifier, 0.040% of xylanase enzyme, and 2.356% of alcoholic sugar sorbitol. The results showed a significant decrease in enthalpy and an increase in the initial gelatinization temperature in the optimal sample compared to the control ones. Also, a weaker gluten network, more swelling, and amounts of starch granules in the microstructure of sample bread were observed. Conclusion In conclusion, SSL emulsifier by interaction with amylose and amylopectin in starch granules, sorbitol alcohol via interacting with water molecules surrounding starch chains or by bonding between starch chains in amorous regions, and xylanase enzyme through reducing rate of crystallization can reduce the gelatinization of starch granules, enthalpy, and finally the retrogradation process of amylopectin and stalling rate of bread with their synergic effects. In this research, we formulate the wheat bran-enriched bread that not only benefits from the nutritional features of wheat bran but also preserves the quality characteristics of bread.
