Characteristics of production-scale tofu as affected by soymilk coagulation method: propeller blade size, mixing time and coagulant concentration

This study was to investigate the effect of soymilk coagulation method on tofu yield and quality. Tofu was produced from Proto and Vinton soybean varieties using an automatic tofu machine. Stirring with a large three-blade (4W x 7L cm) propeller significantly (p less than or equal to 0.05) reduced the amount of calcium sulfate and mixing time when compared to a small three-blade (3W x SL cm) propeller based on the similar tofu yield, protein content and texture. Coagulant concentration had less effect on tofu quality with the small propeller. Calcium sulfate at 19.2 mM in soymilk and stirring 10 s with the large propeller produced Proto tofu with a high yield and sensory quality. Vinton required a different coagulation condition to yield a high quality tofu. The results suggested that the yield and quality of tofu made from different soybean varieties could be improved through modifications of coagulation method. (C) 1999 Canadian Institute of Food Science and Technology. Published by Elsevier Science Ltd. ALI rights reserved.