Food Technology
Marjan Karami; Leila Nateghi; Simin Asadollahi
Abstract
Introduction Oxidation of lipids results in changes that may affect the nutritional quality, wholesomeness, colour, flavour and texture of food. The aim of this study was to investigate the type and amount of phenolic compounds in ethanolic extract of aloe vera gel as a source of natural antioxidant ...
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Introduction Oxidation of lipids results in changes that may affect the nutritional quality, wholesomeness, colour, flavour and texture of food. The aim of this study was to investigate the type and amount of phenolic compounds in ethanolic extract of aloe vera gel as a source of natural antioxidant and its effect on the oxidative stability of soybean oil.Using synthetic antioxidant due to the possibility of toxic and carcinogenic effects is limited. Thus, it is important to find an alternative to synthetic antioxidants by natural antioxidant. Different intrinsic and extrinsic factors may initiate the oxidation of lipids. The initial products of oxidation are tasteless and odorless and after degradation and production of secondary products, the off-flavors and off-odors will appeared in edible oils. This is a great concern in food industry, because it decreases the shelf life of food products. Free radicals are produced during chain reactions in lipid oxidation process. To avoid this, synthetic antioxidants are usually used which are sensible to heat and are hazardous to human health and may cause cancer. Polyphenols have antioxidant activity and absorb free radicals. Thus, the vegetable oils rich in polyphenols can affect human health. In this research, we aimed to investigate the application of natural extract of aloe vera gel as a natural antioxidant to avoid soy oil oxidation and to compare it with synthetic antioxidants.The rate of oxidation reaction can be delayed by adding antioxidants. Consumers today tend to use natural antioxidants instead of synthetics. The overall purpose of this study was to investigate the effect of adding ethanolic extract of aloe vera gel as natural antioxidant on improving the stability of soybean oil. Materials and Methods The compounds in ethanolic extract of aloe vera gel were determined using GC / MS. The antioxidant activity was evaluated by the method of DPPH. For this purpose, ethanolic extracts of aloe vera gel were added to soybean oil in four different concentrations (500, 1000, 1500, 2000 ppm) and peroxide value, acidity, thiobarbituric acid, total phenol, oxidative stability to Rancimat method, fatty acid profile and sensory evaluation were performed on soybean oil samples and compared with the control sample containing 120 ppm BHA and soybean oil sample without adding antioxidants during 30, 60 and 90 days of storage at 25 ° C. Results and Discussion The results showed that by increasing the concentration of aloe vera extracts from 500 to 2000 ppm, the oxidation rate decreases during 90 days of storage, the amount of peroxide, thiobarbituric acid and acidity of soybean oil containing 2000 ppm ethanolic extract of aloe vera gel was lower than the control sample containing 120 ppm BHA. The total phenol content and free radical scavenging and stability to oxidative degradation by Rancimat method in soybean oil sample containing 2000 ppm aloe vera ethanol extract was higher than soybean oil samples containing BHA120 ppm. Evaluation of sensory properties showed that no significant difference was observed between the sensory properties of the oil sample containing 2000 ppm ethanolic extract of aloe vera gel and the control soybean oil sample of BHA120 ppm. Conclusion Considering that the sample of soybean oil containing 2000 ppm ethanolic extract of aloe vera gel had higher phenol content and free radical scavenging and more antioxidant properties than the control sample, it did not differ significantly from the control sample. Qualitative and health properties were selected as the superior treatment. The results of this study showed that the ethanolic extract of aloe vera gel can be used as a natural antioxidant instead of conventional synthetic antioxidants in the oil industry and to prevent oxidative spoilage of the oil in a desirable way. Therefore, it might be employed as a natural antioxidant in foods, particularly those containing edible oils.
Food Chemistry
Atefeh Irankhah; Leila Nateghi; Simin Asadollahi
Abstract
Introduction: Currently, synthetic antioxidants are used to reduce the oxidation of oils and fatty foods and to prevent the reduction of the nutritional value and sensory properties of edible oils. Due to the adverse effects of synthetic antioxidants, the use of natural antioxidants seems essential. ...
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Introduction: Currently, synthetic antioxidants are used to reduce the oxidation of oils and fatty foods and to prevent the reduction of the nutritional value and sensory properties of edible oils. Due to the adverse effects of synthetic antioxidants, the use of natural antioxidants seems essential. Ferulago angulata extract is a natural source of antioxidants that, in addition to enhancing flavor, help extend the shelf life of the product. The aim of this study was to investigate the antioxidant effect of Ferulago angulata extract on the physicochemical and sensory characteristics of potato- chips and the resulting oil during shelf life. Ferulago angulata plant was purchased from the local market of Sarpol-e-Zahab city in Kermanshah province and was extracted using 96% ethanol soaking and solvent by distillation machine. The thin sheets of potatoes were fried in oils containing 1000, 2000, 3000 and 4000 ppm of chamomile extract and the oil containing 100 ppm of synthetic antioxidant TBHQ at 190°C for 9 minutes. The ability to inhibit DPPH free radicals, total phenolic compounds, and sensory evaluation on potato chips and peroxide, acidity, and thiobarbituric acid tests on oil from frying potato chips over time 1, 15 and 30 days of storage were evaluated. The results showed that the use of Ferulago angulata extract increased antioxidant power in inhibiting DPPH free radicals and total phenolic compounds and reduced the amount of peroxide, acidity and thiobarbituric acid, so that the lowest amount of peroxide, acidity. And thiobarbituric acid and the highest amount of total phenolic compounds related to treatment containing 4000 ppm of Ferulago angulata extract. A treatment containing 4000 ppm of chamomile extract has the highest resistance to oxidative spoilage and can be compared to synthetic antioxidant TBHQ. The results of this study showed that using Ferulago angulata extract with a concentration of 2000 ppm, a potato chips with desirable organoleptic properties can be obtained and used as a suitable alternative to synthetic antioxidants such as TBHQ in food and oil oxidation. Materials and Methods: Ferulago angulata plant was purchased from the local market of Sarpol-e Zahab city in Kermanshah province. Then, by Herbarium of Medicinal Plants, Faculty of Pharmacy, University of Tehran, its scientific name was confirmed as Boiss (Schlechat) Ferulago angulata, belonging to the Apiaceae family. 96% ethanol soaking and solvent were used for extraction. For this purpose, 100 grams of powdered leaves of Ferulago angulata plant were carefully weighed by a digital scale balance. Then, to prepare ethanolic extract, 500 ml of 96% ethanol was added to the Erlenmeyer flask. For 72 hours, the flask was placed at room temperature on a 1500 rpm magnetic shaker to fully extract the Ferulago angulata t. The solvent mixture and the plant were then separated by filter paper. Then squeeze the pulp until it is completely emptied and finally the initial extract is obtained. The initial extract was centrifuged for 10 min at 3000 rpm. The resulting extract was then poured into a vacuum distiller (rotary) and heated to 80 °C for one hour to evaporate the solvent from the extract. The concentrated extract contained 4.0623 mg of gallic acid per gram, total phenol and IC50. Ferulago angulata extract in concentrations of 1000, 2000, 3000 and 4000 ppm and TBHQ synthetic antioxidant with a concentration of 100 ppm in frying oil (a mixture of super olein, soybean and sunflower oils) without antioxidants in dark color glass was added and a sample of oil without antioxidants was prepared. Variegated potatoes are washed, peeled and then cut into thin slices using a slicer and immersed in water until fried. Immediately after the dewatering, the potato slices were transferred to a frying pan containing a variety of oils and fried for 9 minutes at 190 °C. The fried sheets were then cooled to room temperature. The frying oil was kept in a 20 °C oven. Then, at 1, 15 and 30 days after storage of frying oil in a 20 °C oven, t the acid number, peroxide and thiobarbituric acid on the oil from frying the potato chips were determined. Sensory and phenolic compounds and DPPH were performed on potato chips. Data analysis was performed using Minitab-16 software and ANOVA. Results and Discussion: The aim of this research was to investigate the antioxidant effect of Ferulago angulata extract on the physicochemical and sensory properties of potato chips and the resulting oil during its shelf life. According to the results, the highest and lowest levels of acidity, peroxide and thiobarbituric acid were assigned to the control treatment (synthetic anti-oxidant oil) and the treatment containing 4000 ppm of Ferulago angulata extract, respectively. Examination of phenolic compounds showed that by using Ferulago angulata extract and increasing its concentration, antioxidant properties increased and the highest antioxidant property was belonged to the treatment containing 4000 ppm of Ferulago angulata extract, which contained higher phenolic compounds. The results of sensory evaluation showed that the highest score of sensory properties was given to the control treatment and treatments containing 1000 and 2000 ppm of Ferulago angulata extract. As can be seen, antioxidant properties and polyphenolic compounds had the opposite effect on sensory scores. The fried chips in oil containing 2000 ppm of Ferulago angulata extract were selected as the optimal treatment in terms of the highest score of sensory evaluation. The results showed that the extract of Ferulago angulata plant could be a good alternative to synthetic antioxidants in frying oils to delay the oxidation of frying oil, and in addition to its antioxidant properties, it can create desirable sensory properties in fried foods and reduce the risk of consuming these foods.
Maryam Zaeri; Simin Asadollahi; Mahnaz Hashemiravan
Abstract
Introduction: Fat substitutes are the compounds that use for providing all or some fat properties, while producing fewer calories than it. It is noteworthy that in confectionary products, carbohydrate-based fat substitutes are more used than other substitutes because of having other technical and economic ...
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Introduction: Fat substitutes are the compounds that use for providing all or some fat properties, while producing fewer calories than it. It is noteworthy that in confectionary products, carbohydrate-based fat substitutes are more used than other substitutes because of having other technical and economic benefits and one of these substitutes is gum. In this regard, in the present research, the effects of locust bean gum and xanthan gum as a fat substitute on the physicochemical, rheological and sensory properties of oil cake were studied.
Materials and Methods: Treatments included: A0 (control), A1 (0.2% (w/w%) xanthan and 0% locust), A2 (0.4% (w/w%) xanthan and 0% locust), A3 (0.6% (w/w%) xanthan and 0% locust) B1 (0.2% (w/w%) locust and 0% Xanthan), B2 (0.4% (w/w%) locust and 0% Xanthan), B3 (0.6% (w/w%) locust and 0% Xanthan), C1 (0.1% (w/w%) locust and 0.2% xanthan), C2 (0.2% (w/w%) locust, and 0.2% xanthan), C3 (0.3% (w/w%) locust, and 0.3% xanthan), D1 (0.4% (w/w%) locust, and 0.2% xanthan) and D2 (0.2% (w/w%) locust and 0.4% xanthan). In order to produce an oil cake, in the first step, the eggs, the sugar and emulsifier in the formulation were completely mixed by mixer with high speed for 3 minutes. In the second step, the oil and water were added to the mixture and mixed by the mixer with high speed. In the third step, flour, vanilla, baking powder, invert syrup and salt were added and mixed for 3 minutes at medium speed. In the fourth step, the dough obtained from the previous stage was poured into the desired molds and cooked in an oven at 175 o C for 30 minutes. Finally, the cakes were packed in polyethylene bags and stored at room temperature. The tests performed on the dough included the density, viscosity and specific weight, as well as tests on the final product included the measurement of moisture, aw, volume, color, fat, height and sensory tests. On the other hand, to evaluate the effect of xanthan gum and locust gum on cake texture, the test of firmness was performed on days 1, 7 and 15. In order to analyze the data obtained from the experiment (except for the instrumental analysis of data on the staling conducted by using a factorial experiment in a completely randomized block design), a completely randomized design with three replications was used and the mean comparisons were conducted by Duncan's multiple range test, at the probability level of α=1% and by SPSS software version 16.
Results and Discussion: According to the results, adding gum at different levels increased the viscosity of the dough samples compared to the control. The reason for the results is that the reaction between the gums and the protein of flour, especially gluten, leads to the strength of the gluten network and the increase in viscosity of the dough. According to the results, with the addition of different levels of gum, the density of dough decreased, some reasons of which can be water absorption and the amount of air bubbles in the dough. According to the results, by increasing gum content, the moisture content of cake samples increased due to the presence of hydroxyl groups in these compounds that form a hydrogen bonding with water, resulting in the stability of the gluten dough network, better preservation of dough water, reduction of the staling and firmness of the product. Also, by increasing the amount of gum, the fat content of the samples decreased. The reason for decreasing the fat in the cake samples containing the gum was to use them in the formulation of produced cakes instead of oil. On the other hand, the height of the cake is directly related to the volume of the samples, so that the height of the cake samples will be decreased by decreasing the volume, which it is consistent with the results obtained in this study. According to the results obtained in this study, when the amount of gum used in the product structure increased, the amount of fat decreased, and gradually the height of the desired cakes also increased. Then, the volume of samples increased by increasing gum content. The reason for increasing in volume of the samples containing gum is increasing the viscosity of the dough, slowing down the gas release rate, maintaining it in the early stages of cooking, and thus retaining CO2 and water vapor in the air cells. According to the results, the addition of gum increased the L * color index compared to the control sample. The reason for the increase of L* color index in gum-based treatments can be attributed to the dark color of gums, and on the other hand, to the reaction of becoming brown in the formulation of cake production. Adding the different gum levels also decreased a* color index. This is due to the moisture content in the crust, the intensity of the Maillard reaction, and the amount of light and bright colored compounds in the cake. According to the results, adding different gum levels decreased the b* color index in the treatments containing it. Also, increasing the levels of xanthan and Locust gum consumption decreased the staling of samples. According to the results, the addition of gums to the treatments increased the sensory scores of flavor due to the presence of aldehyde compounds in xanthan and locust gums. Addition of Locust bean and xanthan gums also increased the sensory score of color. The reason for this result can be attributed to the Maillard reaction. Overall, the addition of different levels of gums increased the total acceptance score of samples compared to the control sample, which can be attributed to the presence of xanthan and locust gums which have the special and proper work properties. Finally, according to the results, D2 treatment was introduced as the best treatment.
Nafiseh Ravatab; Simin Asadollahi; Mohammad Reza Eshaghi
Abstract
Introduction: Chocolate is a complete and correct process of mixing one or more primary ingredients with the cocoa beans. These raw materials include the edible sweeteners or sugar, dry milk powder, edible essential oil and flavors as well as plant kernels. Despite high levels of fat and sugar, chocolate, ...
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Introduction: Chocolate is a complete and correct process of mixing one or more primary ingredients with the cocoa beans. These raw materials include the edible sweeteners or sugar, dry milk powder, edible essential oil and flavors as well as plant kernels. Despite high levels of fat and sugar, chocolate, has a significant contribution to human nutrition through the supply of antioxidants and polyphenols. It also has the beneficial minerals, especially potassium, magnesium, copper and iron. Milk chocolate is a complex rheological system that includes the solid phase (cocoa powder, sugar powder and no-fat dry milk powder) released in the continuous phase of cocoa butter. As mentioned, the chocolate contains three essential ingredients in foods, namely, protein, carbohydrate and fat, along with essential minerals that considering its physicochemical properties, the property of functionality can be activated in it by adding certain materials. The first member of omega-3 family is the alpha-linolenic acid that is not produced in the human body, hence it is called essential fatty acid and plays a very important role in many physiological responses of the human body and is considered as a necessity in the diet. The plant resources are healthier, cheaper, and more accessible. The highest amount of fatty acids, α-linolenic acid (short omega-3 chain), was found in plants. Among the plants, flaxseed has the highest fatty acid content (about 50%). Considering the above-mentioned cases, the possibility of producing the functional milk chocolate containing omega-3 fatty acid by this plant resource was investigated.
Materials and Methods: The treatments included control, L10, L20, L30 and L40 with the amounts of 0, 10, 20, 30 and 40% of flaxseed powder replacing butter, cocoa powder, dry milk and sugar. The experiments conducted included the study of physicochemical (sugar, fat, acidity, moisture content, peroxide, ash, particle size, texture and omega-3 levels) and sensory properties. In order to analyze the data of the research, a factorial experiment was used in a completely randomized design and the mean comparison was conducted by Duncan's multiple range test at the probability level of α =5%.
Results & discussion:The results obtained by studying the effect of adding flaxseed powder on the physicochemical properties, color, texture and sensory properties of functional milk chocolate showed that the addition of this material does not have a negative effect on the chemical properties of any treatment. The biggest concern was the oxidation of the oil in the flaxseed powder, which was solved with keeping conditions at 4 ° C and in none of the treatments the amount of peroxide did not increase more than the standard of chocolate (2%). On the other hand, the moisture content of the chocolate remained at the standard level due to the proper packaging and dry storage. Chocolate produced had a bitter taste in L30 and L40 treatments, despite having a good amount of sugar and dry milk powder, due to the relatively bitter taste of flaxseed oil and powder, but this bitterness was not so bad and unpleasant in L10 treatment. Chocolate acidity was not changed undesirably by adding flaxseed powder and replacing some of its oil with cocoa butter. Since the particle size of the flaxseed powder was more than that of cocoa powder and sugar, it reduced the volumetric surface, and fewer chemical bonds was formed between the hydrophilic and hydrophobic surfaces, resulting in less storage time of product at room temperature. Of course, this problem was less significant in L10 treatment, but in L30 and L40 treatments an inappropriate texture were found. The amount of omega-3 residues was zero in L10 and L20 treatments and was not detected by chromatography device, which indicated an inadequate ratio of antioxidant and flaxseed powder. However, since the maximum allowed antioxidants were used in chocolate, more amount of flaxseed should be used, so that as L30 and L40 treatment this fatty acid remains in the chocolate and does not oxidize. Also, by increasing the amount of flaxseed powder in treatments, viscosity also increased, due to the large size of particles and the lack of adequate bonding between hydrophilic and hydrophobic parts. Of course, this indicator was so high in L40 treatment that a problem was even created in molding. The texture analysis behavior of the chocolate indicated that the chocolate texture was loose in L40 treatment so that it lacked the value of production. The texture of this treatment was so loose that it became doughy at ambient temperature. In terms of sensory properties, a significant difference was found between the treatments and the control sample, indicating a decrease in the quality of chocolate produced. Overall, L40 treatment score was low due to so weak and doughy texture, inappropriate and bitter taste, the relatively dark color and the presence of many large pieces of flaxseed powder on chocolate. Therefore, its production does not seem logical, despite the proper amount of omega-3. L30 treatment had more desirable condition, but here, the texture was relatively loose too due to the presence of coarser flaxseeds. Of course, covering the bitter taste of flaxseed with sugar and dry milk powder and vanilla improved the opinion of the experts and increased their scores. It is noteworthy that the appearance and color of the product had better quality than L40 treatment. Regarding L10 and L20 treatments, although the scores of experts were better and they had better texture, color and flavor than two L30 and L40 treatments, but they did not have justifiable production due to the lack of remaining omega-3 in them that was the main purpose of this study. Totally, considering all properties, L30 treatment was introduced as the best treatment.
Sanaz Ojnordi; Majid Javanmard; Simin Asadollahi
Abstract
Due to environmental risks generated by application of non-degradable and synthetic films, many researches have shown increasing tendency to edible coatings for storing food such as fruits and vegetables. Whey protein is considered one of the most common sources of edible coatings and its use has been ...
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Due to environmental risks generated by application of non-degradable and synthetic films, many researches have shown increasing tendency to edible coatings for storing food such as fruits and vegetables. Whey protein is considered one of the most common sources of edible coatings and its use has been studied in the current research. In this paper, the simultaneous effect of coating with whey protein and Zataria multiflora Boiss extract on the quality of peach kept in refrigerator has been studied. According to response surface methodology, were measured 20 treatments repeating 6 times in the center point and effects of the three factors including whey protein (2. 5 to 5 gr), Zataria multiflora Bioss extract (0 to 500 μL) and glycerol (0. 375 to 2. 25 gr) on the physicochemical characteristics, fungal decay and organoleptic traits of peach, were investigated in the condition 5±2 ̊C and 80% relative humidity during 21 days of storage. According to the results, by increasing Zataria multiflora Bioss extract concentration and whey protein of the coating, microbial decay and weight loss of the fruit was reduced and texture and soluble solids were conserved. Peel colour changes of the coated fruit was not significant compare to control and the coated samples had a light and bright colour. Coating peach resulted in natural ripening of the fruit and the coated fruits were softer and juicier than the fruits without any coating. The coating formulations had significant effect on TSS and TA. Optimized points of variables for achieving a coating with the maximum effect on shelf life improvement of peach (Prunus Persica cv. Anjiri) are: whey protein 4. 7475 gr, Zataria multiflora Bioss extract 498. 00 μL and glycerol 0. 6212 gr.
