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 Whipped cream is one of the most popular dairy products with a complex structure of foam emulsion. Production of low fat whipped cream with fat substitutes is recommended with regard to the high fat content in whipped cream and side effects of fat on the public health. Based on, the effects of whey protein concentrate, carboxymethyl cellulose, xanthan gum and mix of them were investigated on the properties of low fat whipped cream. For this purpose, different amounts of them were determined by the surface response design and then they were added to the cream with 20% fat. Then, apparent viscosity, cream firmness, particle size distribution, foam stability, overrun tests, sensory evaluation, color characteristics (L *, a *, b *) were done on the samples. The results showed that fat substitutes in low fat whipped cream compared to the control sample were increased the apparent viscosity, overrun, firmness, foam stability and change in particle size (p<0/05). However, the stabilizers had no alone statistically effects on the color factors. Also, whey protein concentrate in compared with other treatments had the highest overrun and lowest particle size, xanthan gum had the lowest water leakage and carbohydrates, especially xanthan, had the highest viscosity and firmness (p<0/05). Based on the sensory evaluation data, optimal sample that contain 0.35 whey protein concentrate and 0.15 xanthan and carboxymethyl cellulose had statistically more desirable than control and other treatments in texture and overall acceptance. At the end, we pointed out that these additives could be a good alternative to reduce the percentage of fat in whipped cream due to they improve the physical, rheological and sensory properties of whipped cream without significant effects on the most of external parameters such as color and sensory.

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Celiac disease is the most common disease caused by gluten consumption and the only way to prevent it is to use gluten-free foods. The aim of this study was to optimization the formulation of gluten-free bread based on quinoa flour, laccase enzyme, and xanthan gum. For this purpose, the sensory properties and texture of bread under the influence of independent variables including quinoa flour (0-50%), xanthan gum (0-0.5%), and laccase enzyme (0-2 units of enzyme activity per gram of flour (U/g) were evaluated using the response level method based on the central composite design. Then some qualitative characteristics of gluten-free bread sample in optimal conditions were compared with the control sample (gluten-free bread containing rice and corn flours without quinoa flour, laccase enzyme, and xanthan gum) for 7 days of storage. The results showed that quinoa flour and laccase enzyme had a significant effect on sensory properties including crust color, porosity, taste, aroma, firmness, and overall acceptibility (p<0.05) of breads. While the effect of quadratic level of gum on overall acceptibility as well as the interaction of laccase enzyme and xanthan gum on bread firmness was significant (p<0.05). The optimal bread formulation consisted of 40% quinoa flour, 0.46% xanthan gum, and 2 U/g laccase enzyme. Comparison of the gluten-free optimal sample with the control gluten-free sample showed that the enthalpy and peak temperature of the control bread was higher than the optimal bread, which indicates more staleness. In terms of textural properties and sensory evaluation, the optimal sample was significantly better than the control sample. However, in terms of L* color indice, the control sample showed higher values (p<0.05).