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Background and Objective: Chocolate is one of the most popular food products, which, despite its desirable nutritional and health effects, can cause health risks/problems in consumers due to its high energy content. One way to reduce these risks/problems is to replace the sucrose with low-energy prebiotic compounds.The objective of the present study wasto explore the possibility of replacing sucrose with inulin, polydextrose, and maltodextrin in producing a low-energy dark chocolate with prebiotic properties using a Simplex Lattice Mixture Design. Materials and Methods: Sucralose (an artificial sweetener substituted for sucrose), was used along with inulin (a prebiotic), polydextrose and maltodextrin (bulking agents) with different ratios (0, 25, 50, 75 and 100%) to produce samples of a dark chocolate. The physicochemical (pH, water activity, and moisture, fat, and protein contents), mechanical and rheological (hardness, viscosity and yield value), as well as sensory (sweetness, firmness, mouth coating, and color) properties of the samples were examined. Results: The results showed that chocolate samples containing high levels of sugar substitutes had the highest moisture content and viscosity, as well as lower hardness. Out of the 5 mathematical models tested to predict the rheological characteristics of the chocolates produced, the Casson model was found to be the most suitable. There were no statistically significant differences between the treated and control samples as regards sensory characteristics. Furthermore, the results of superimposed contour plot showed optimum ranges to be 0–6% and 11–15% for inulin, 22–38% and 64–79% for polydextrose and 21–31% and 62–77% for maltodextrin. Conclusion: The findings show that a low-energy dark chocolate with prebiotic functional food properties can be produced using a low-energy sweetener (substituted for sucrose) and bulking agents (to improve rheological and sensory properties). Such a chocolate can compete with ordinary dark chocolate and can be consumed by children, adults and dieters with little restriction. Keywords: Dark chocolate, Inulin, Polydextrose, Maltodextrin, Rheology, Prebiotic

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Background and Objective: Cup cake is one of the foods that fat replacement can be used in its preparation. In this study, the application of flaxseed mucilage (as fat replacer) in reducing the fat content in cake formulations was investigated, and its effect on the characteristics of low-calorie cake and batter was then evaluated. Materialsand Methods: Flaxseed mucilage extraction was performed. In order to produce low calorie cake, different percentages of fat were considered. Optimization of the reaction and the optimum level of each variable were conducted by response surface methodology using design expert software. Any changes in batter viscosity and cake firmness were monitored, and based on the model, optimum formulation was obtained. The tests were carried out to examine the properties of optimized formulation, including viscosity, specific gravity of batter and volumetric index of cakes. Then the results were analyzed by SAS software. Results: Variables of the model (water, mucilage and fat) were effective on the viscosity and texture, as linear and quadratic levels, respectively there was an interaction between the water and mucilage content. According to the results, there was no significant difference between the measured and predicted viscosity of the batter and firmness of the cake. The optimum conditions (p<0.05) were determined as 71.53% water, 1.60% mucilage and 10.38% fat. then the properties of batter and cake at optimum conditions were studied. It was observed that viscosity and specific gravity of the optimized batter formulation were more than those of the control (p<0.05). Volumetric index of the optimized cake was higher than that of the control (p<0.05). In respect to sensory evaluation, there was no significant difference between the optimized (low-calorie) and control cakes (P<0.01). Generally, the results indicated that production of low-calorie cake by using flaxseed mucilage as fat replacer is possible, so that the lipid levels could reduce to 76.40%. Conclusion: By using flaxseed mucilage, fat content can be reduced without considerable decrease in the product quality. Keywords: Low-calorie cup cake, Fat replacer, Flaxseed mucilage, Response surface methodology

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Background and Objectives: Recently, the use of synthetic antioxidants has been limited due to having chemical and toxic compounds, so the use of natural compounds such as algae, as an alternative to synthetic compounds, is important for the storage of fishery products. The aim of this study was to investigate the effect of Padina australis alga extract on controlling the oxidative spoilage of muscle of  Epinephelus coioides during refrigerated storage.

 Materials & Methods: Extraction of algae was performed using methanol. The fish were immersed in four different levels of the extract including 0 (control), 150, 300 and 600 mg/L, and were immediately stored in refrigerated polyethylene bags for 12 days. Sampling was carried out on days 0, 3, 6, 9 and 12 to measure lipid oxidative indices.

Results: The results showed that the amount of peroxide, thiobarbituric acid, anisidine and Totox value at 300 and 600 mg/l levels of algae extract decreased significantly from day 9 comparing to the control treatment (p <0.05). There was no significant difference between the conjugated diens’ indices in different treatments and days (p> 0.05). The amount of free fatty acids only decreased in the 600 mg/L treatment comparing to the control treatment (p <0.05).

Conclusion: Algae extract at 600 mg/L concentration had high antioxidant effect; in this concentration, oxidative degradation indicators were in the standard range until the end of the storage, so it can be used as an alternative to synthetic compounds in food.