The moisture content of a fermented sample was determined by infrared moisture determination balance
(FD-720, Kett Electric Laboratory, Tokyo, Japan). The fermented matter was mixed with deionized water (1:2
w/v) by blender and the pH value was measured by pH meter (DKK-TOA, HM-25G, Japan).
Casein solution (0.65%) in 0.05 M phosphate buffer (pH 6.9) and 0.05 M carbonate buffer (pH 10) were
used as a substrate to analyze neutral and alkaline protease activity, respectively