Food Chemistry
Farideh Mojrian; Marzieh Moeenfard; Reza Farhoosh; Hadi Mahdavian Mehr
Abstract
Introduction: Date seeds (also known as pits and kernel) are among the most important wastes which are generated during direct consumption or from the date processing industries. Despite the presence of several nutrients and bioactive compounds and their subsequent beneficial health effects, these by-products ...
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Introduction: Date seeds (also known as pits and kernel) are among the most important wastes which are generated during direct consumption or from the date processing industries. Despite the presence of several nutrients and bioactive compounds and their subsequent beneficial health effects, these by-products are frequently discarded to use as soil fertilizer or as feed for livestock. Roasting opens a cost-effective way to include date seed in the human diet. The aqueous extract of roasted date seed represented a coffee-like beverage. Date seed coffee has a relatively low acceptance among consumers and is usually supplemented with a variety of additives to improve the taste. Therefore, due to rising the global coffee price, in the present studywe aimed to substitute Arabica beans with roasted date seeds in order to make a coffee beverage similar to Coffea Arabica boiled coffee brew. Results and Discussion: Substitution with roasted date seed resulted in lower lipids, protein and caffeine of coffee brews as the values were decreased from 330.67, 956.75, 76.51 mg/100 mL in Coffea Arabica (100%) to 192.61, 149.00, 45.59 mg/100 in date seed coffee (100%), respectively. Higher amounts of date seed also resulted in lower pH and acrylamide content. Accordingly, pH was decreased from 5.7 in D100 to 4.4 in A100. Acrylamide content was attenuated from 5.06 µg/100 mL in A100 to 1.71 µg/100 mL in D100. Reduction in viscosity was also observed from 0.93 (A100) to 0.86 mPa.s (D100). The mean value of the color parameter including L*, a* and b* in the 100% Coffea Arabica brew was more than the 100% date seed coffee, which indicated that the coffees brewed from date seeds in different proportions were brighter and had higher red and yellow color parameters. Substitution with date seed had less effect on the total phenol content as TPC of coffees ranged from 28 to 42 mg/100 mL for 100% date seeds brew and Coffea Arabica brew, respectively. On the other hand, the flavonoid content (TFC) of coffees was significantly affected by the amount of date seeds (5 to75 mg/100 mL for 100% date seeds and Coffea Arabica brew, respectively). All brews have high antioxidant activity. For DPPH the highest results (88/9 %) were obtained in the coffee brewed from 100% date seeds, while the FRAP value it was vice versa. The results of sensory evaluation indicated a high similarity among A100 and D10 coffees as parameters such as aroma, color and texture (concentration) of coffee were evaluated appropriate. The results also showed that substituting Coffea Arabica up to 35% with roasted date seeds can improve the overall acceptance of the coffee brews by reducing bitterness.Conclusion: In general, the ability to replace Coffea Arabica with date seeds up to 10 and 35% was reported acceptable in terms of sensory characteristics, as the color and aroma were similar to 100% Coffea Arabica. Besides that due to reduced bitterness, the overall acceptance were almost high.
Food Technology
Dornoush Jafarpour; Parisa Ataei
Abstract
Introduction: Every year during marine fishing, some species that are caught are not suitable for human consumption and they are known as surplus fishing or low consumption, which is an important factor in wasting these rich resources. Therefore, it is necessary to set arrangements to use such species ...
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Introduction: Every year during marine fishing, some species that are caught are not suitable for human consumption and they are known as surplus fishing or low consumption, which is an important factor in wasting these rich resources. Therefore, it is necessary to set arrangements to use such species for human consumption, including the production of surimi. The surimi industry mainly uses Alaska pollock fish as the main source for surimi production. However, due to the increase in the world’s population and partly the depletion of the fish stocks, followed by a reduction in the surimi production of Allaska Pollock fish (due to restrictive fishing laws), the need to use new species is considered urgent. In this regard, additives such as gums can be used to reform and improve the properties of surimi. Therefore, in this study, the possibility of producing surimi paste and gel from Lizardfish and Talang Queenfish was investigated and the effect of Konjac on the physicochemical properties of the product produced from these two types of fish was evaluated. Materials and methods: In this study, Talang Queenfish and Lizardfish with approximate weight of 225.9±33.6 and 275.9±24.4 g and average size of 15.1±2.4 and 17.3± 2.6 cm, respectively, were purchased freshly from the fish market. After preparing surimi paste from both types of fish, Konjac gum in concentrations of 0.25, 0.50 and 0.75 % (w/w) was added directly to the surimi paste. Then to prepare surimi gel, first, the samples were placed in a water bath at 25 ° C for 3 hours for setting and then cooked at 90 ° C for 20 minutes. After that, the prepared gels were cooled in iced water immediately. The produced paste and gel were evaluated in terms of chemical composition, water holding capacity and color factors. Texture and sensory characteristic were assessed on the produced gels of both types of fish and compared with the control sample (without gum). Results and discussion: According to the results, the yield of Lizardfish was 28% and Talang Queenfish was 22%. It seems that the larger size of Lizardfish has been effective in its higher yield than Talang Queenfish. Based on the results, the percentage of ash, protein and fat in the treatments did not change significantly compared to the control sample. Also, there was no significant difference between the two types of fish in the amount of mentioned factors (p>0.05). As the contraction level of Konjac gum increased, the amount of moisture and water holding capacity of the paste samples of both fish increased significantly, which is due to the absorption and binding of water by the Konjac hydrocolloid. The lightness level (L*) of the surimi paste and gel of both types of fish increased significantly with the addition of Konjac, which is related to the increase in water content in the samples. The lightness of the surimi paste and gel of Lizardfish was higher than that of Talang Queenfish, which is due to the presence of more pigments in the Talang Queenfish meat. Control Sample and treatment of 0.25% of Talang Queenfish surimi paste showed more yellowness and redness than Lizardfish, but in the resulting gel, their values were reduced, indicating that the formation of gel structure by Konjac gum and binding to the proteins covered the yellowness and redness of the samples. By increasing the concentration of Konjac in surimi gel of both fish the parameters of texture (firmness, cohesiveness, adhesiveness, springiness, chewiness) breaking force and deformation increased significantly compared to the control sample. Also, the results showed that the surimi gel from Lizardfish has higher firmness, cohesiveness and strength than Talang Queenfish. Sensory evaluations showed that the panelists assigned the highest score for the surimi gel from Lizardfish to the 0.5% treatment and for the Talang Queenfish to the 0.75% treatment of Konjac. Based on the findings of the present study, it was found that surimi gel from Talang Queenfish has a lower quality than Lizardfish, but with the addition of Konjac gum, its properties can be improved.
Food Technology
Delaram Hami; Mohammad Goli
Abstract
Introduction: Ice cream contains a mixture of milk components, sweeteners, stabilizers, emulsifiers, and flavorings. The quality of the finished product depends not only on the processing conditions or the freezing efficiency, but also on the constituents, the amount of entrapped air, and the number ...
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Introduction: Ice cream contains a mixture of milk components, sweeteners, stabilizers, emulsifiers, and flavorings. The quality of the finished product depends not only on the processing conditions or the freezing efficiency, but also on the constituents, the amount of entrapped air, and the number of ice crystals. The physical structure of ice cream has a significant effect on the melting properties (melting rate) and texture (hardness) of ice cream (Mouse & Hartel, 2004). The improvement and expansion of the ice cream structure are attributed to the macromolecules present in the ice cream mixture; milk fat, protein, and carbohydrates (Adapa et al., 2000). Quinoa as a high biologically valuable protein can be used in various food products to enrich and positively affect the physical and sensory properties of the product (James, 2009). The purpose of the present study was to replace skim milk powder with quinoa flour (0 to 100%), hydrogenated vegetable oil (4.5 to 8.5%) and Panisol gum (0.25 to 0.65%) to obtain the optimal formulas of Vanilla ice cream using the response surface methodology. Materials and Methods: After adjusting the ratio of the ingredients in the various ice cream formulations, the amount of raw material of each formula was weighed. The milk was then heated to about 45 ° C, and then the remaining ingredients were slowly added and thoroughly mixed. The mixture was then pasteurized at 85 °C for 15 minutes. After the pasteurization operation, the mixture was immediately kept in a water-ice bath and cold down for 4 hours in a 4 °C refrigerator. After the ripening step, the mixture went through the freezing phase in a homemade ice cream maker. The ice cream samples were packed in plastic containers and stored at -18 °C for the period of hardening. To optimize the process conditions, the independent variables A (quinoa flour replacement from 0 to 100%), B (hydrogenated vegetable oil from 4.5 to 8.5%) and C (Panisol gum from 0.25 to 0.65%) were selected at five levels. To obtain optimal points, 34 experiments were recommended by design expert software. The volumetric overrun (%) and the melting rate (g/min.) were measured according to Hashemi et al., (2015) method. Ice cream textural properties were tested after 3 days storage at -18 °C using a Brookfield texture analyzer. It was equipped with a cylindrical probe with a diameter of 6 mm and a height of 15 mm. The probe was applied to the test samples twice at a speed of 1 mm / s and up to 50% of the probe height and the results were recorded by device software. Ice cream textural data used in this study included hardness (g) and adhesiveness (g. sec) (Hashemi et al., 2015). Results and Discussions: Reducing overrun of ice cream samples by increasing the replacement levels of quinoa flour can be attributed to an increase in the viscosity. As viscosity increases, due to the reduced mixing ability of the ice cream mixture, the ability of air to enter the mixture of ice cream containing quinoa flour has been reduced during freezing (Gelroth et al., 2001). The reason for the decrease in the melting rate of ice cream with increasing percentage of quinoa flour replacement can be attributed to the existence of polysaccharide compounds with high water holding capacity, which led to increase the product water intake intensity and viscosity and subsequently decreasethe overrun. One of the factors affecting the melting properties is the increase in volume. In addition, the role of quinoa flour in enhancing the melting resistance of ice cream can be attributed to the type of protein content, the emulsifier potential and the surface active properties of its proteins and lipids. The presence of high amounts of protein in quinoa flour has a significant effect on the stability of air molecules. Since quinoa flour contains high amounts of protein, this fraction of flour quinoa protein, increases the hardness of ice cream through creating hydrogen bonds between the amide-hydroxyl and hydroxyl-carbonyl groups with other polar groups of other ice cream components such as panisol gum. In addition, hydrogen bonds are likely to be formed by electrostatic interactions between the quinoa protein groups of the polar with the polar part of the gum panisol, which may also be the reason for the increased hardness of the ice cream in the presence of the quinoa flour. With polar groups, quinoa flour traps the water in its structure and ultimately increases the consistency and adhesiveness of the ice cream. It is also possible that the protein portion of quinoa flour binds to the water molecules present in the sample through hydrogen bonding and ion-dipole and dipole-dipole interactions, thereby reducing water activity, increasing sample adhesiveness (Fatemi, 2008). The optimal formulas were predicted for replacement of skim milk powder with quinoa flour at 25 and 53%, hydrogenated vegetable oil 8.5 and 8.2% and panisol gum 0.39 and 0.48%, respectively.
Hassan Sabbaghi; Aman Mohammad Ziaiifar; Mahdi Kashani-Nejad
Abstract
Introduction: Fruits and their products in the dried form are good sources of vitamins, energy and minerals. However, during the process of drying or dehydration there are changes in quality parameters in dried products. Texture is one of the most important quality attributes of fruits during drying, ...
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Introduction: Fruits and their products in the dried form are good sources of vitamins, energy and minerals. However, during the process of drying or dehydration there are changes in quality parameters in dried products. Texture is one of the most important quality attributes of fruits during drying, reflecting their mechanical and microstructural properties. Apple is perishable fruit. Drying of apple is very important because of High losses are experienced during the seasonal glut. A novel process in food industry is the simultaneous infrared dry blanching and dehydration operation (SIRDBD) with intermittent heating method (radiation at constant temperature) exerted on fruits and vegetables that is known to enhance the quality of the final product. In the food industry, end-products must achieve a compromise between several properties, including sensory, sanitary and technological properties. Prediction of changes in texture during drying could be helpful in a better process control and improvement in overall acceptability of a dried snack food. The change of the elastic or viscoelastic texture of the fresh apples to rigid, fragile and brittle in the apple chips were evaluated by instrumental and sensory methods. Many attempts have been made to describe the viscoelastic behavior of dehydrated fruits and vegetables. Maxwell’s or compression models are limited to homogeneous, isotropic materials. In contrast, texture profile analysis (TPA) is more suitable for heterogeneous biological materials and shows a good correlation with organoleptic evaluation. Typical TPA parameters are including hardness, adhesiveness, springiness, cohesiveness, gumminess, chewiness and resilience. In this research, for the first time, textural analysis of dried apple slices by infrared heating at different temperatures and different moisture levels was performed. Finally, the optimum texture and overall acceptance of the product are described according to the instrumental analysis. Materials and methods: Apples (Golden Delicious variety) were purchased from a local market and kept in 0°C±1°C and relative humidity ranging from 90% to 95%. Before every thermal processing, the apple specimens were picked up from the cold storage and then they were put into use after reaching the ambient temperature. The samples were skinned manually and then cut into slices with different thicknesses of 5mm, 9mm and 13mm, all 20mm in diameter. The sliced apples were immediately subjected to simultaneous blanching and infrared drying. The texture of dehydrated apple slices using infrared radiation at three surface temperatures of 70, 75 and 80 °C were studied. The product in three thicknesses was dried to achieve a moisture level of 15, 20 and 25% wet weight basis. Then, texture profile analysis (TPA) was carried out to 50% compression strain using texture analyzer. The sensory evaluation of dried slices was also considered for desire texture (Good mouth feels texture, lack of hard tissue, no shrinkage) and overall acceptance (The final acceptability of the product in terms of total sensory properties including color, texture, flavor and aroma) by 10 professional panelists. For statistical analysis, a completely randomized design (CRD) was used in a factorial form (33) and Duncan test with 95% confidence level. Result & Discussion: The results showed that drying to studied moisture levels reduced the hardness and adhesiveness and increased springiness, cohesiveness, gumminess, chewiness and resilience in comparison with raw apple tissue. Hardness of samples dried at higher temperature was higher due to rapid removal of moisture which might have caused collapse of capillary voids inside the product. Due to shrinkage samples became denser and thus a larger fracture force was to be expected. As water content increases (i.e., higher RH) water plasticizes the cell walls and the material and product becomes softer and more pliable, thus hardness decreases. The increase of hardness could be because the rapid mass transfer that damaged the membrane and cell structure of the fruits during drying. Another important factor responsible for the increase of hardness of finish-dried samples is the low final moisture content when compared with other samples. High temperature drying method enables samples to reach low moisture content at relatively short duration and therefore the product with harder texture was obtained. The maximum value of adhesiveness was observed for fresh apples, which could be attributed to the high moisture and sugar content. Adhesiveness decreased with moisture loss, indicating the availability of free water on the sample surface. A significant decrease in springiness following high-temperature drying could be attributed to the glass transition phenomenon and changes from elastic to plastic behavior. In the period of softening, cohesiveness increased with moisture loss. Hardening caused a decrease in cohesiveness depending on the drying temperature. Gumminess is the energy required to disintegrate a semisolid food to a state of readiness for swallowing. High values of gumminess revealed “firm” and “crisp” with a cell rupture mode of tissue failure and lowest values of gumminess could be classified as “soft”. At the end of drying and with apple hardening, chewiness increased to values equal or above initial chewiness, indicating that a larger amount of energy is needed to masticate dried apples. Resilience had increasing with moisture loss. By increasing the thickness of the slices, the cohesiveness and springiness decreased and hence chewiness significantly decreased. The overall acceptance and desire texture in dried samples was observed at lower water evaporation rate conditions (lower temperatures, lower thickness and higher moisture content). In these conditions, the hardness of apple slices tissue was equal to 695.177 ± 7.685 grams. During drying of the apple, textural behavior was varied from the viscoelastic (higher initial hardness, with cohesiveness, springiness and lower resilience) to elastic and then to plastic or glassy.
Fahimeh Tooryan; Maryam Azizkhani
Abstract
Introduction: Nowadays, consumers are applicant to usage of natural replacements causing to side effects of synthetic preservatives such as carcinogenicity and teratogenicity. The tendency to use natural preservatives and replacing them with chemical preservatives has led to various studies of natural ...
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Introduction: Nowadays, consumers are applicant to usage of natural replacements causing to side effects of synthetic preservatives such as carcinogenicity and teratogenicity. The tendency to use natural preservatives and replacing them with chemical preservatives has led to various studies of natural compounds with antioxidant properties such as essential oils. Considering the environmental problems raised from current plastic packaging, edible and biodegradable coating could be developed and also be effective in controlling the chemical and microbial properties of food; especially if their effect be strengthened by adding natural antioxidant and antimicrobial agents like herbal essential oils. Various herbal compounds such as black pepper essential oils with antioxidant properties can be effective in combining with natural biodegradable coatings such as chitosan in oxidation control and enhance the effects or prevent or delay the chemical spoil. Safety and shelf-life of foods can be improved by using this technologies such as using natural preservatives. Adding essential oil, as a suitable source of antioxidant, for improvement the quality of the fish is the main purpose. Many fruits, especially orange, are rich in polyphenols. These materials are the most commonly existing phytochemicals in most fruits. Orange juice concentrate can be a good source of antioxidant and can be employed as a preservative in food products. Omega-3 fatty acid is used in daily healthy diet and plays an important role in prevention of disease. Being a considerably main source of Omega-3 fatty acid groups, fish preservation against oil oxidation and any other similar causatives seems quite necessary. In the present study, the effects of orange juice concentrate and chitosan coating enriched with black pepper essential oil on the chemical degradation of rainbow trout fillet stored in a refrigerator investigated.
Materials and methods: The chemical composition of black pepper essential oils were determined using a gas chromatography equipped with mass spectroscopy (GC/MS). GC-MS analysis of the essential oil was performed using Agilent-Technologies 6890N Network gas chromatographic (GC) system, equipped with Agilent Technologies 5975 inert XL Mass selective detector and Agilent-Technologies 7683 B series auto injector (Agilent-Technologies, Little Falls, CA, USA). Samples were stored at 4 ± 1 C° up to 12 days and evaluated periodically ( on days 0, 4, 8 and 12) for chemical and sensory characteristics. The samples were divided into 8 groups and assessed for PH-values, total volatile nitrogen (TVN), thiobarbituric acid (TBA), peroxide value (PV), free fatty acids (FFA) and sensory evaluation .The samples were also evaluated for antioxidant activity by measuring their scavenging abilities to DPPH radical (2,2 diphenyl-1-picril hydrazyl) and RP (Reducing power). Statistical analysis was performed using SPSS 20 software.
Results & Discussion: Results showed that More than 21 compounds were identified in oil, representing 97.75% of the total oil. The major constituents of essential oils obtained from the black pepper were β-caryophyllene (25.56%), Limonene (15.19%), Sabinene(12.2) , α-copaene(8.5) and beta –bisabolene (7.81) respectively. Results revealed that in comparison to the other treatments the control showed a significant increase in the trend of oxidative and sensory indexes and In the coated samples, the sample of fish coated with orange juice concentrate ,chitosan, and black pepper essential oil was the least amount of indexes than the rest (p<0/05) and showed lower indexes during the storage time .The radical scavenging DPPH, orange juice concentrate with a Brix 1/39 (66/9 %)and pepper essential oil 2% (64/1%) have more ability and had a greater antioxidant activity. In investigating corruption oxidation and sensory evaluation in all samples,chitosan coating with pepper essential oil and orange juice concentrate was higher(score:7/2) than other treatments and there were significant differences between treatment and control (p<0/05). Final peroxide value (meq O2/Kg oil) and tiobarbituric acid (m gr/kg oil MD) number using chitosan coating with pepper essential oil and orange juice concentrate in sample was 0.14 and 0.015, respectively. This significant deference was also observed when comparing to control sample (p<0.05)Minimum oxidative changes were observed in samples treated with orange juice concentrate,chitosan, and black pepper essential oil and had the best conditions in reduction of oxidative rancidity. The results obtained in this study showed that the chitosan coating enriched with black pepper essential oil with orange juice concentrate has a good potential to being employed as an active packaging to preserve food products. Overall, this study demonstrated that using concentrated juice incorporated with chitosan coating with pepper essential oil has a good effect on the quality of rainbow trout fillets and can keep on the sensorial attributes acceptably during 12 days storage time and present a good potential for their application in the food industry.
Safura Jalali; Hossein Jalali; Seyyed Hossein Hosseini Ghaboos
Abstract
Introduction: Cakes by appropriate organoleptic characteristics are considered the most commonly used flour products all over the world. According to the role of dietary fiber on health and its ability to prevent some types of cancer and diabetes, fans of high-fiber foods is increasing. Pumpkin is a ...
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Introduction: Cakes by appropriate organoleptic characteristics are considered the most commonly used flour products all over the world. According to the role of dietary fiber on health and its ability to prevent some types of cancer and diabetes, fans of high-fiber foods is increasing. Pumpkin is a good source of carotene, water-soluble vitamins and amino acids. Pumpkin can be converted to powder with longer shelf-life. Pumpkin flour is used because of its highly-desirable flavor, sweetness and deep yellow orange –red color. In this study, kinetic modeling of pumpkin drying in an infrared-hot air dryer was investigated. Malting is a result of biochemical processes that includes steeping, germination and kilning of cereal in controlled environment in which hydrolytic enzymes are synthesized and cell wall, protein and starch of endosperm are largely digested. The aim of this study was to determine the physico-chemical, textural and sensory properties of sponge cake supplemented with four different levels (0, 10, 20 and 30 %) of pumpkin and malt powder
Materials and methods: Fresh pumpkins (Cucurbita moschata) were obtained from local market. Slices of pumpkin with 5 mm thickness were prepared with the aid of a steel cutter and were immediately placed into the dryer. The pumpkin slices were dried in a hot air dryer (65°C). The effect of pumpkin and malt powder replacement with wheat flour on physicochemical and sensory properties of sponge cake including pH, fat, protein, moisture, ash, fiber, β-carotene, mineral, carbohydrate, texture and color were evaluated. The ingredients used in the sponge cakes formulation were cake wheat flour, sucrose, sunflower oil, fresh eggs, whey, baking powder, vanilla, water and nonfat milk powder. In this study pumpkin and malt powders at four levels of 0, 10, 20 and 30 % as wheat flour replacer were used. For each cake, 40 g of cake batter was poured into a cake pan and baked at 180-200°C for 20-25 min in an oven. Cakes were then allowed to cool for 40 min, and removed from the pans. The cooled cakes were packed in polypropylene bags at room temperature before performing physico-chemical and sensory evaluation s. Moisture content of the samples was determined in an oven at 105°C for 4 h (AOAC, method no. 934.06). For measuring β – Carotene content 1 gram of cake was dried and then crushed in 10-15 ml of acetone with the help of pestle and mortar and few crystals of anhydrous sodium sulphate were added. The supernatant was decanted into a beaker. The process was repeated twice and combined supernatant was transferred to a separating funnel, then 10-15 ml of petroleum ether was added and mixed thoroughly. Two layers separated out on standing. The lower layer was discarded and upper layer was collected in 100 ml volumetric flask. The volume was made to 100 ml with petroleum ether and optical density was recorded at 452 nm using petroleum ether as blank. The crumb color determinations of cake samples from the midsection of the cakes was measured with HP Scanner (Hp Scanjet G3110). L* (lightness/darkness that ranges from 0 to 100), a*(redness/greenness ranges from -120 to 120) and b* (yellowness/blueness ranges from -120 to 120) were measured. In this study, the image analyses of sponge cakes were performed using Image J software version 1.42e, USA. The texture analysis of sponge cake samples (2.5 × 2.5 × 2.5 cm) from the midsection of the cakes was performed using a texture analyzer (TA-XT Plus, Stable Micro Systems Ltd., Surrey, UK) and a test speed of 1.0 mm s−1. The crust of cake samples was removed in cake texture determination. The textural properties were determined using Texture Expert 1.05 software (Stable Microsystems). Each measurement was conducted in triplicate, except for the sensory evaluation (n=16). The experimental data were subjected to analysis of variance (ANOVA) for a completely random design using SPSS 19 and Excel 2010. Duncan’s multiple range tests were used to determine the difference among means at the level of 0.05.
Results & Discussion: The results showed no significant differences between treatment on fat, protein and pH. With increasing of pumpkin and malt powder in sponge cake formulation, significant difference was observed between the fiber contents of cakes. Fiber contentof all treatments was in the range of 0.28-1.13. Redness (a*) and yellowness (b*) indexes of cakes were increased but lightness (L*) index was decreased. Significant difference (P
Zeynab Raftani Amiri; Mohammad Ezazi
Abstract
Introduction: Nowadays, use of by products in formulation of functional foods in order to improve their nutritional value and also avoid environmental pollution in food industry is increasing. Whey, a by product of dairy industry is one of such compounds. The acid whey resulted from concentration of ...
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Introduction: Nowadays, use of by products in formulation of functional foods in order to improve their nutritional value and also avoid environmental pollution in food industry is increasing. Whey, a by product of dairy industry is one of such compounds. The acid whey resulted from concentration of yoghurt, as a by-product, can be applied in whey based fruit beverages due to its minerals and beneficial residual proteins. It represents about 85–95% of the milk volume and contains nutrients, such as lactose as a most content, soluble proteins, lipids, minerals, vitamins, and organic acids. Acid whey has a pH of approximately 4.5 due to the conversion of lactose into lactic acid by lactic acid bacteria during the process of yoghurt production. Lactose is the main ingredient of whey, which comprises 90 percent of whey dry matter. According to FAO, the worldwide production of cheese was estimated to be 19,000 kilo tones (kt) in 2010, thus resulting in approximately 177,000 kt whey as a by product. The annual growth arises to production of approximately 211,000 kt whey in 2020. Therefore, the research for new lucrative whey utilization beside whey protein recovery is an ongoing challenge for the dairy industry. More than 70% of the world’s population suffer from lactose intolerance, which limits consumption of lactose containing dairy products. Lactose intolerant individuals, who consume milk or other dairy products like as acid whey, even at small quantities, facing gastroenterological complications related to the uptake of calcium and certain other nutrients. Thus it is important to reduce the lactose content of mild and dairy by products before using them in new foods formulation. In this study production of low lactose whey by enzyme was investigated. Beta-D-Galactosidases, EC (3.2.1.23), is a hydrolase enzyme that converts lactose into glucose and galactose and increases the sweet taste in products. It is commonly known as lactase, which is one of the most important enzymes in food, dairy and fermentation industries. Mixing of the low lactose whey with fruit compound or concentrates and sweetener agents make delicious and functional new beverage.
Materials and methods: The acid whey resulted from concentration of Greek yoghurt, as a by-product, was applied in whey based fruit beverages. The lactase enzyme (Sapherra FMP) was prepared from Novozyme Company. Pineapple compound prepared by Orana Company from Denmark. The quantity of sugar (Shadianeh) in each sample has been investigated based on the equivalent sweetness recognition by panelists in lactase treated samples in comparison with non treated samples. Premixed sugar and stabilizer in precise amount for each treatment was added to water and agitated in stainless steel agitating mix. After that whey and pineapple compound, and then 1000 ppm enzyme were added to samples and kept at 4 degree Celsius for 3 hours and finally pasteurized. All samples homogenized by 150 bar in 60 degree Celsius. Packaging of samples was done in 250 gram tetra pack container at aseptic condition. The effect of lactase enzyme on sugar quantity and taste improvement of acid whey based beverage produced by 5 percent of pineapple compound, has been investigated by lactase enzyme (0 and 0.1 percent), acid whey (30 and 40 percent), storage temperature (ambient and refrigerator) and time storage (0, 4, 8, 10 and 12 weeks after production) on a factorial experiment in a completely randomized design.
Results and discussion: The results of sensory evaluation in 12 weeks at two different storing temperatures (refrigerator and ambient), showed that addition of lactase enzyme before pasteurization of whey based pineapple flavored compound could kept not only the pH on constant, and reduced the sugar quantity to achieve constant sweetness in all samples, but also improved the sensory specification of beverage, significantly (p
Hadi Bagheri; Mahdi Kashani-Nejad; Mehran Alami; Aman Mohammad Ziaiifar
Abstract
Introduction: Roasting is one of the processing steps involved in the nut industry to improve the flavor, color, texture and overall acceptability of the product. Ppeanut is a fruit or pod of the order Leguminosae and contains 47–50% oil, 25–30% protein and is an essential source of minerals and ...
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Introduction: Roasting is one of the processing steps involved in the nut industry to improve the flavor, color, texture and overall acceptability of the product. Ppeanut is a fruit or pod of the order Leguminosae and contains 47–50% oil, 25–30% protein and is an essential source of minerals and vitamins; thus it makes a substantial contribution to human nutrition. Peanuts are readily acceptable as a cheap protein source and popular snack item that can be eaten alone or combined with other foods. Recently, peanuts have gained much attention as functional food and roasted peanuts is one of the most popular snack foods, in which roasting is a key step in the process and directly impacts the quality (crispness, taste, and flavor) and shelf-life of the final product. Understanding of the roasting process is of interest because roasting is a critical processing step not only for peanuts, but many other food products such as coffee, cocoa, grains and other tree nuts. Roasting is a process to develop color, flavor and textural characteristics of product through chemical reactions, therefore proper roasting is critical to flavor and texture development as well as nutritional content of the final product.
Materials and methods: In this study, dried Goli peanuts were supplied from a local market in Minodasht, Iran in 2015 and stored at 4°C until processing. The average moisture content of peanut kernels was measured as 5.1 % (d.b.). Kernels were sorted manually to get the uniform sizes for roasting. 100 g peanut kernels were soaked in 500 ml of 25% salt solution for 30 min. After soaking, the salt solution was drained using a strainer and the excess water was removed by a cloth filter. After soaking, the moisture content of soaked peanut kernels increased to 8.27 % (d.b.). For roasting, three temperatures (140, 160 and 180°C) and three times (10, 20 and 30 min) and constant air velocity (1 m/s) were applied. Roasting was performed in a hot air roaster equipped with a controller to adjust the roasting temperature. After roasting, the whole kernels were allowed to cool at room temperature (23 ± 2°C). Roasting process was performed in 3 replications. Instrumental texture measurements (Uniaxial compression test) were carried out at room temperature using a TA-XT Plus Texture Analyzer using cylinder probe (diameter 25 mm) on peanut halves. The textural parameters of peanut halves were expressed as fracture force (initial peak or first fracture force (N)), hardness (highest peak compression force (N)), initial tangent modulus or apparent modulus of elasticity that shows sample rigidity in the linear part of the force-deformation curve (N/m) and compressive energy or area under the curve for the compression that is the work (N×m) required to attain deformation, indicative of internal strength of bonds within product. Sensory attributes including colour, texture, flavor, odour, total acceptance and final acceptance were assessed according to a five-grade hedonic scale (5 points – the best, 1 point – the worst). A completely randomized factorial design was used to evaluate the results and analysis of variance (ANOVA) was carried out to compare the mean values. All significant differences were reported at P ≤ 0.05 levels. Minitab statistical software (Minitab Release 16, Minitab Inc., USA) was used for all statistical analyses in the present research. However, MSTATC (Version 2.10, Michigan State University) was used to determine significant differences.
Results & discussion: Roasting is one of the most important steps in peanuts processing that leads to the development of the desired aroma, taste, texture and color of the final product. The results showed that increasing the roasting temperature and time decreased the fracture force (75.19–45.92 N), instrumental hardness (81.74–48.90 N), apparent modulus of elasticity (7.508-5.446 N/s), compressive energy (469.0–199.1 N.s) and improved the sensory characteristics of peanut kernels. During roasting process, moisture content of peanut kernels decreased and they became more crumble and fragile which causes to break easier and moisture reduction helps to create a desirable crisp texture. The results of the consumer test showed that the roasted peanut kernels have good acceptability for color (4.50), texture (4.15), flavor (3.89), odor (4.05), total acceptance and final acceptance (3.97) on roasting temperature and time (160°C and 30 min). The results obtained for VIP coefficients (standard coefficients) in PLS regression for fracture force, instrumental hardness; apparent modulus of elasticity and compressive energy variables indicated that apparent modulus of elasticity could be able to predict the individual sensory attribute of peanut kernels except color. PLS results showed that apparent modulus of elasticity could successfully predict quality sensory characteristics of peanut kernels. Thus, instrumental apparent modulus of elasticity could be replaced with sensory analysis for evaluation the quality of peanut kernels.
Esmail Khazaei; Fakhri Shahidi; Seyed Ali Mortazavi; Mohebbat Mohebbi
Abstract
Introduction: Kiwifruit (Actinidia sp.) has many appealing properties for consumers such as flavor, color, and nutritional content, especially vitamin C. Kiwi seems to be used as one of the major ingredients within the formulation of this category of foods.Microalgae are nutritional and innovative natural ...
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Introduction: Kiwifruit (Actinidia sp.) has many appealing properties for consumers such as flavor, color, and nutritional content, especially vitamin C. Kiwi seems to be used as one of the major ingredients within the formulation of this category of foods.Microalgae are nutritional and innovative natural sources that can be used in the development of novel foods. Among the known species of algae, Chlorella vulgaris and Spirulinaplatensis are common edible microalgae that have no side effects on health of human. The amino acid, carbohydrate, and fatty acid profiles of these microalgae are very similar to those of other food materials. Spirulina is a multicellular filamentous blue-green microalga, which was introduced as generally recognized as safe (GRAS) after being approved by food and drug administration (FDA). Spirulina can also be incorporated into common food preparations such as pastas, biscuit, bread, snack,pastille, candy, yoghurt, soft drink, causing health-promotion that are associated with microalgae biomass.The aim of this study was to investigate the possibility of producing new product based on kiwifruit and its enrichment with Spirulinaplatensis microalgae so that this product could replace common snacks, especially the pastilles containing synthetic colors and flavors, which have increasingly been used day by day despite having a low nutritional value and causing a variety of side effects. The role of pHysicochemical and sensory properties is very important in producing new products which can help producers design the products suitably. Therefore, some of the pHysicochemical properties of the kiwi base pastille were examined in this study, as well as the formulation and enrichment of it with Spirulinaplatensis. Material and methods: The ingredients of the formulations consist of 65% w/w kiwifruit puree, 30% w/w sweeteners (sugar, powdered glucose, invert syrup and sorbitol), 0.25% w/w high methoxyl pectin, 0.5% Agar, 0.5% Guar and Spirulinaplatensis(0, 0.25, 0.5, 1 and 2% w/w) as well.In order to produce fruit pastille based on kiwifruit puree, the kiwifruits were fist washed up, peeled and cut into pieces. Then the pieces were grinded. The prepared puree was mixed with Spirulinaplatensis, hydrocolloids and sweeteners at 70°C with specific ratios. Agar was dissolved in distilled water at 90°C and added to the concerned mixture. Finally, after moderating pH to 3.4 by adding 40 M citric acid and controlling the Brix degree in constant Brix of 45, the mixture was prepared. The mixture was then poured into stainless steel mesh molds with cavity dimensions of 1.2 cm × 2 cm × 2 cm and the molds were kept at 4°C for 2 hours to form the gel. Then the obtained gel was taken out of the mold cavities and the samples were dried at 70°Cfor 6 hours in a hot air drier with 1.5 m/s airflow rate. Then the regarded tests were performed on the dehydrated samples. To measure pH, pH meter (Hana, Portugal) was used. The measurement of mixture Brix was performed by an optical refract meter (Carlze, Germany). The drying process of the samples was conducted in a hot air drier (Soroush Medicine Co. Iran).Moisture, protein, fiber, lipid, ash, vitamin C, calcium and iron elements were measured according to the Iran national standard.Texture profile analyzer (QTS25 CNS Farnell England) equipped with a software was used to determine the textural properties of the samples. Samples were compressed and decompressed in two reciprocating cycles by a round plate cylindrical probe with 3.5 cm diameter, 1 mm/s probe speed and 5 g force to 30% initial height.Histological properties obtained from force-deformation curve are as follows: Hardness, Cohesiveness, Elasticity, Adhesiveness and Chewiness.Sensory test was performed with the judgment of 10 trained panelists. In order to evaluate the samples. A 9-point Hedonic method (1: very undesirable - 9: very desirable) was used. 5 sensory attributes (color, texture, flavor, odor and overall acceptance) were evaluated.SPSS software was used for the statistical analysis of the parameters. Mean of the replicates were compared via the multi-range Duncan`s test at 95% confidence level.In order to pHotograpHy with Scanning electron microscope, initial preparation should perform on all of samples.The obtained sampleswas removed from the templates and were sectioned on a scale of 2×1×1mm. samples were dehydrated in ethanol solution and then dried in a critical point. Then samples with 30 nm of gold/palladium coated and were tested using SEM (model LEQ1450VP) in the maximum voltage of 15 kv. At least four images with magnification of 500, 1000, 2000 and 5000 were prepared in several different areas of the samples.Results and discussion: The obtained results indicated that the effect of Spirulinawas significant on the moisture content and increasing Spirulinaconcentration led to increased moisture content of the product.The results of texture profile analysis indicated that the hardness and chewness was increased, but the cohesivness of samples was decreased when the amount of Spirulina is increased. The amount of protein, vitamin C, total ash, iron and calcium was increased by increasing the amount of Spirulina. SEM microscopic results showed that adding up Spirulina is led to the reduction of the uniformity of sample’s structure and then the gel matrix will be created with a larger pore. Results of sensory analysis indicate that samples containing 0.25% Spirulina have sensory characteristics (color, aroma, flavor and overall acceptability) than other samples.
Esmail Khazaei; Fakhri Shahidi; Seyed Ali Mortazavi; Mohebbat Mohebbi
Abstract
In this research, the production of a new kiwi- based product by applying kiwi puree, agar (0.25, 0.5 and 1%), guar (0.25, 0.5 and 1%) and other formulation ingredients (kiwi puree, sweeteners and pH modulators) has been investigated. Dependent variables include moisture content measurement, instrumental ...
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In this research, the production of a new kiwi- based product by applying kiwi puree, agar (0.25, 0.5 and 1%), guar (0.25, 0.5 and 1%) and other formulation ingredients (kiwi puree, sweeteners and pH modulators) has been investigated. Dependent variables include moisture content measurement, instrumental texture analysis and sensory evaluations were carried out in a factorial design and the means were compared at significance level of 5 % by Duncan test. The results indicated that guar had a significant effect on the moisture content of final product. Textural properties of the kiwi pastille were influenced by the type and amount of hydrocolloids. Synergistic effects of agar and guar on the textural properties were also observed. While all products were acceptable regarding sensory properties, the samples prepared with 1% agar and 1% guar obtained the highest score.
Asal Gachpazian; Sodeif Azadmard Damirchi; Javad Hesari; Seyed Hadi Peighambardoust; Mahbub Nemati; Sadegh Alijani; Effat Ahmadi
Abstract
Milk and dairy products are in diet almost every day. Milk fat contains 70% of saturated fatty acids which can cause an increase in total and low-density lipoprotein cholesterol, and the risk of cardiovascular diseases. Therefor, modification of fat composition at dairy products such as yoghurt seems ...
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Milk and dairy products are in diet almost every day. Milk fat contains 70% of saturated fatty acids which can cause an increase in total and low-density lipoprotein cholesterol, and the risk of cardiovascular diseases. Therefor, modification of fat composition at dairy products such as yoghurt seems necessary. Walnut has high amount of essential fatty acids, anti oxidants and other beneficial components. In this study, ground walnut is added to yoghurt at level of 0 (control sample), 3, 6 and 9% and their texture properties (synersis and viscosity), sensory, fatty acids profile and dry matter were analysed every week for 4 weeks during storage. Results showed that fortification of yoghurt samples with ground walnut and storage had significant effects ( ) on synersis, viscosity, fatty acids profile and dry matter. Control sample had the highest synersis and the lowest viscosity and dry matter among samples. By adding ground walnut to yoghurt samples, the amount of saturated fatty acids decreased and the amount of unsaturated fatty acids increased. Major fatty acids of yoghurt incorporating ground walnut were linoleic acid, oleic acid, linolenic acid, palmitic acid and stearic acid, respectively. The highest final score in sensory evaluation in 1, 14 and 28 days of storage time were for yoghurt samples with 9% of gorund walnut, yoghurt with 6 and 3% of ground walnut and yoghurt with 3% of gorund walnut, respectively. Results of this study showed that adding ground walnut modifies yoghurt fat composition, forify it with essential fatty acids and also has good effect on its texure properties.
Roya Rezaee; Fakhri Shahidi; Mohammad Elahi; Mohebbat Mohebbi; Mehdi Nasiri mahalati
Abstract
In this research, the production of plum pastille-like with starch and gelatin was studied. Thirteen formulation of plum pastille-like were prepared according to a second-order composite rotatable design (with five central points). Response surface methodology (RSM) was used to optimize product formulation ...
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In this research, the production of plum pastille-like with starch and gelatin was studied. Thirteen formulation of plum pastille-like were prepared according to a second-order composite rotatable design (with five central points). Response surface methodology (RSM) was used to optimize product formulation with: gelatin concentration ranging from 3.85 to 6.925 % (w/w), and starch concentration ranging from 0 to 3.85 % (w/w) as independent variables. The dependent variables were texture objective evaluation and total acceptance obtained from sensory analysis. The texture and flavor attributes of the samples were identified and evaluated by a trained descriptive panel. The thickeners strongly affected texture and flavor attributes of the samples. The resulting polynomial equation (R2=0.9325) revealed that a formulation with 5.38% gelatin and 3.85% starch had a maximum total acceptance.
