7603

7075

كارشناسي ارشد

علوم و صنايع غذايي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1391

دوازده،123ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

علي نصيرپور، جواد كرامت

19/1/92

ميلاد فتحي، غلامرضا قرباني

مهندسي كشاورزي

ID7075

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Effect of Whey Proteins Modification by Thermal Treatment and pH Adjustment on Physical and Stability of Low fat Whipped Cream Abstract Whey is a by product of cheese making and casein manufacture in dairy industries It is considered as one of the most polluting by product in environment Otherwise whey is an excellent source of functional proteins that can be used in food industry for example dairy foods bakery products infant foods and beverages Extensive physical treatments were investigated to modify whey proteins in order to improve their functionalities Among these thermal treatment is one of the most effective methods Heat treatments can be used to improve the foaming properties of whey proteins Whipping cream is a high consumption of dairy products that is a complex emulsion structure based on foam It is highly desirable due to its special flavor but because of the high fat content the nutrition experts recommend avoiding consumption of this product Thus researchers are seeking a replacement for fat that in addition to creating the appropriate texture the flavor will not be damaged In this research effort WPC structure modified using thermal processes at different pH Then their ability to as a fat replacer in the whipping cream was evaluated In 9 WPC solution with pH adjusted in three pH values of 3 2 5 2 and 7 2 the thermal process at a temperature of 80 C and three times 5 12 5 and 20 minutes was performed After preparation of the stabilizer there physical propertieses such as amount of insoluble aggregates turbidity of WPC dispersions Intrinsic fluorescence spectroscopy and particle size distribution were investigated Then these stabilizers added to whipping cream with a fat percentage of 25 30 and 35 at concentrations of 1 2 and 3 percent Then after various examinations the effects of these factors were investigated using RSM design Analysis showed that pH of thermal process of whey proteins and fat percentage of whipping cream have a significant effect on overrun viscosity syneresis and firmness of the final product Also time of whey proteins heat treatment process has significant effects on viscosity and firmness In addition the percentage of stabilizer also has a significant effect on the viscosity and overrun of the final product Keywords Aggregate pH Thermal treatment Whey Proteins Whipping Cream

علي نصيرپور، جواد كرامت

ميلاد فتحي، غلامرضا قرباني