Food Technology
Azade Farazmand; Hossein Jalali; Ali Najafi
Abstract
Introduction Potato strips are one of the most widely consumed products, and due to their high oil content, they have caused public health concerns. Therefore, efforts to reduce oil absorption can alleviate these concerns to some extent. Edible coating is an effective way to reduce oil uptake, because ...
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Introduction Potato strips are one of the most widely consumed products, and due to their high oil content, they have caused public health concerns. Therefore, efforts to reduce oil absorption can alleviate these concerns to some extent. Edible coating is an effective way to reduce oil uptake, because the oil absorption is a surface phenomenon. Edible coatings should adhere well to the surface of the product and provide a uniform and complete coverage for the product. Preventing the migration of oxygen, carbon dioxide, aromas, oils, moisture, improving the appearance of food and mechanical properties. In this study, the possibility of reducing oil absorption in French fries was investigated using okra mucilage and chitosan as edible coatings. Material and Methods The okra was washed and then cut into about 1 cm pieces and poured into containers with lids. Then water in a ratio of 2:1 weight of okra was added to the container and completely covered its surface. The okra were refrigerated for 72 hours until the mucilage was completely extracted. Then the mucilage was smoothed. This solution was considered as 100% mucilage solution. To prepare a 50% solution of okra mucilage, 100% solution was mixed with an equal amount of distilled water and filtered. To produce a solution of 0.75 and 1.5% of chitosan, 7.5 and 15 g of chitosan powder was dissolved in 1000 ml of 1% acetic acid and then adjusted to pH 5. Then 5 g of glycerol was added as a plasticizer. The potato slices were first blanched in 0.5% calcium chloride solution at 90°C for 5 minutes. Then, they were immersed in coating solutions at 60°C for 5 minutes. After coating, the potato strips were fried at 180°C using a fryer and then various characteristics including coating percentage, oil absorption, and moisture content, texture firmness, peroxide value, acid number, color indices and sensory properties were examined. Design Expert 8.0.7.1 software was used to analyze the results and to draw the curves. Results and Discission The results showed that the increasing the amount of chitosan led to better coating formation in comparison with okra. The highest coverage was observed in the concentration of 1.2% chitosan and 0% okra mucilage (2.38%) and the lowest was observed in the control sample (0.11%). It was also observed that with increasing the concentration of chitosan and okra mucilage, the amount of oil absorption decreases. However, the amount of oil absorption in high concentrations of okra mucilage increased slightly. The highest oil uptake in the control sample was 20% and the lowest was observed in the sample of fried strips covered with 41% okra mucilage and 1.5% chitosan at 15.44%. The obtained model of oxidation index was not significant. The effect of okra mucilage and chitosan concentration on the texture of the samples (p <0.05) and the color indices of a* (p<0.01) and L* (p <0.05) were significant. For sensory attributes, the highest and the lowest taste score was observed for samples coated with 100% okra mucilage and 0.75% chitosan and samples coated with 18% okra mucilage and 0% chitosan respectively. Conclusion The aim of this project was to reduce the oil absorption of fried potato strips by coating them with chitosan and okra mucilage. Optimization to minimize the consumption of okra and chitosan mucilage showed that coating with 74% okra and 0.89% chitosan is suitable for coating potato slices. The desirability of this optimization was 71%, which is a reasonable percentage.
Seyed Mohsen Mortazavi; Hossein Jalali; Seyed Hamidreza Ziaolhagh
Abstract
In this study, the probiotic bacterium Lactobacillus acidophilus with different percentages of pomegranate peel powder (0, 0.5, 1, 1.5, and 2%) were used to produce a functional camel milk-based beverage. The physicochemical, antioxidant and sensory properties of the resulting drinks were evaluated. ...
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In this study, the probiotic bacterium Lactobacillus acidophilus with different percentages of pomegranate peel powder (0, 0.5, 1, 1.5, and 2%) were used to produce a functional camel milk-based beverage. The physicochemical, antioxidant and sensory properties of the resulting drinks were evaluated. The results showed that enrichment of milk with pomegranate peel powder improved the survival of probiotic bacteria from 6.95 to 7.35 Log CFU/ml. Addition of pomegranate peel to beverages increased their antioxidant activity from 7 to 85.33, 9.13 to 93.66 and 0.126 to 0.435 as measured by DPPH free radical scavenging, ABTS+ free radical scavenging and reduction potency tests, respectively. Rheological studies also showed that the addition of pomegranate peel powder to beverages increased their viscosity from 5.65 to 21.5 mPa. Adding pomegranate peel powder to beverages also changed the color factors (L*, a* and b*) so that increasing the level of pomegranate peel powder increased the red and yellow color in the samples. Also, the results of the sensory evaluation, including taste, appearance, smell and general acceptance indicated that the produced beverages were well-liked by consumers. However, the results of sensory evaluation showed that adding high percentages of pomegranate peel powder to beverages could reduce the sensory acceptance of the final product.
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