With Dangshan pear as raw material,color protection and concentration process in the processing of pear paste were optimized. The terminal concentration point and rheological type of pear paste were determined. The best ratio of pear paste composite color protection was determined by single factor experiment and orthogonal experiment. Then,the optimal temperature of vacuum concentration was determined by single factor experiment. Finally,the study compared the quality differences with the congeneric product. The results showed that the terminal concentration point of pear paste was 69 °Brix,and the pear paste belonged to pseudoplastic non-Newtonian fluid with shear thinning phenomenon. The optimal technical parameters for pear paste composite color protection was citric acid 0.7 %,ascorbic acid 0.04 % and sodium chloride 1.1 %. And the optimal vacuum concentration parameters for pear paste were also obtained. The vacuum concentration temperature was 70 ℃,vacuum degree was -0.1 MPa and the rotary speed was 60 r/min.
Food Research and Developent
terminal concentration point