Table 2.

Box–Behnken experimental factors and coding levels

Code	Variable	The coding level
		− 1	0	1
A	Initial temperature  °C	33	35	37
B	Enzymolysis time h	1.5	2	2.5
C	Enzyme additive amount mL	2.25	2.5	2.75
D	Substrate moisture  %	38	40	42