Recently, the quality of powder product was considered in food industry. Foam mat drying is an economical alternative to spray, drum and freeze-drying for the production of food powders. The high porosity and surface-to-volume ratio of foams during foam-mat drying improve final product quality. In this work, foaming properties of white button mushroom(Agaricusbisporus) were analyzedby response surface methodology. For optimization,xanthan gum (XG)solution range was considered between 0.05–0.3% w/w, mushroom concentration (water: mushroom puree) range was considered 1:0.5– 1:3.5 w/w and whipping time range was considered between 2–8 min. Based on face centered central composite design (CCF),twenty tests were done. Analysis of variance showed that the quadratic modelshaveconsiderable effects on both responses.In this research, the optimized pointwasobtainedat xanthan gum solution 0.2% w/w, mushroom concentration (water:mushroom puree) = 1:2.2 and whipping time= 6.19 minand the predicted values for foam density and drainage volumewere0.56 gcm-3 and 1.8 mL, respectively.At the second step, optimized foam dried at 50, 65 and 80°C and then drying behavior of optimized foam was investigated by different mathematical models. The results indicated that theMidilli model is high accurate model for evaluating the drying behavior of mushroom foam. At the third step, the influence of the drying temperatures on some qualitative characteristics of foam-matdried mushroom powder was investigated. It was found, as the temperature increased, water activity and water binding capacity decreased. Also, Lightness parameter for the temperature of 65°Cwas higher than other temperature.So, white button mushrooms can be processed into powder and used as a functional or nutritional addition in a variety of food products.

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