Microbiological and Chemical Changes During the Production of Acidic Whey, A Traditional Chinese Tofu-Coagulant

Abstract

In this study, acidic whey (AW), a natural tofu-coagulant in China, was investigated for the micro flora and chemical changes of AW during tofu whey natural fermentation. The gel properties of AW tofu coagulated with AW were also studied. Throughout the fermentation stages, the change of lactic acid bacteria (LAB) was found to be similar to that of total mesophilic aerobic bacteria (TMAB), implying that LAB is the most important role that works on AW fermentation. The numbers of enterobacteriaceae, yeast and mould (fungi) were too low to detect. Bacterial spores (spores) and acetibacteria was found to increase slowly with fermentation time. The pH value, protein, carbohydrate, organic acid changes during the production of acidic whey were studied. It was found that the pH value of acidic whey had a significant effect on the gel properties of AW tofu. The microbiological findings in this study have clearly demonstrated the presence of the high counts of LAB investigated and a large amount L-lactic acid produced by LAB must have act as the main tofu coagulant.

Keywords:

• acidic whey
• micro flora
• acidic whey tofu
• gel properties
• Chinese

ACKNOWLEDGMENTS

This study was conducted within the framework of the collaborative research project between Japan and China titled “Development of sustainable production and utilization of major food resources in China” supported by Japan International Research Centre for Agricultural Sciences (JIRCAS).