Improving Gelling Properties of Tofu: Study on ApnA Aspartic Protease Enzyme Impact on the Resulting Chemical and Microstructure Properties

Title : Improving Gelling Properties of Tofu: Study on ApnA Aspartic Protease Enzyme Impact on the Resulting Chemical and Microstructure Properties

Abstract:

This study investigated the prospective effect of ApnA enzyme under different concentrations (µL/100 mL soymilk) compared to chemical (pH, MgCl2, and K-carrageenan, respectively) as tofu coagulants. The resultant tofu samples were analyzed for compositional analysis, thermal properties, water distribution, and microstructure properties. The higher concentration of enzyme used, the higher resulted moisture content of tofu. ApnA enzyme increased the cross-linking through protein mol ecules and trapped more water within the gel network. Tofu samples prepared by different concentrations of ApnA enzyme displayed significantly less freezable water content (15.44, 12.84, and 19.46 g/100 g). In particular, 800 µL ApnA/100 mL soymilk formed an interconnected gel matrix with regular distribution with almost invisible cavities. The thermal pretreatment and the increased coagulation time might encourage this irregular structure. On the other hand, the gel network coagulated using the reduction of pH showed a weaker gel due to an accelerated acidification.

Biography:

Fatma Ali received her Ph.D from Tianjin University of Science and Technology, Tianjin, China. Since 2019, she works at Department of Biological Chemical Engineering, College of Chemical Engineering and Materials Science, Tianjin University of Science and Technology, Tianjin, China. She is the first author of more than 11 peer-reviewed papers in Food Engineering (https://www.researchgate.net/profile/Fatma-Ali-43). She collaborates with Food Science and Technology researchers on the regular basis. Her area of interest is dairy technology, non-thermal techniques, milk proteins, plant based food, and food chemistry. She has published a various papers in peer reviewed journals (Trends in Food Science and Technology, Carbohydrate polymers, Food Bioscience, International Journal of Dairy Technology, Journal of Food Process Engineering, etc). Fatma is an Editorial Board Member in International Journal of Dairy Technology (IJDT).