Table 2.

Box–Behnken design variance analysis.

Source	Sum of Squares	df	Mean Square	F Value	p-Value Prob > F	Significance
Model	84.95	14	6.07	15.33	<0.0001	**
X1-Temperature	2.88	1	2.88	7.28	0.0173	*
X2-pH	1.75	1	1.75	4.42	0.0542
X3-Time	0.89	1	0.89	2.24	0.1569
X4-Enzyme dose	2.65	1	2.65	6.7	0.0215	*
X 1 X 2	0.9 × 10−3	1	0.9 × 10−3	2.27 × 10−3	0.9626
X 1 X 3	0.1	1	0.1	0.26	0.619
X 1 X 4	2.5	1	2.5	6.31	0.0249	*
X 2 X 3	2.15	1	2.15	5.42	0.0354	*
X 2 X 4	13.88	1	13.88	35.05	<0.0001	**
X 3 X 4	0.4	1	0.4	1.02	0.33
X 1 2	6.23	1	6.23	15.74	0.0014	**
X 2 2	19.98	1	19.98	50.48	<0.0001	**
X 3 2	39.34	1	39.34	99.37	<0.0001	**
X 4 2	18.31	1	18.31	46.26	<0.0001	**
Residual	5.54	14	0.4
Lack of Fit	4.73	10	0.47	2.35	0.2134
Pure Error	0.81	4	0.2
Cor Total	90.49	28

* Significant (p < 0.05); ** Extremely significant (p < 0.01).