Changes of the enzyme activity during koji-making in Beijing surrounding areas

By tracking and monitoring the koji-making process of four soy sauce factories in Beijing surrounding areas,changes of different enzyme activities including neutral protease,acid protease and alkali protease,amylase,cellulase,glutamine and leucine aminopeptidase were analyzed.The results showed that the enzyme activities are significantly different from factories though the koji was made in the same process and the current brewing process could not produce sufficient enzymes with high activity.