Preparation of ACE Inhibitory Peptides from Mytilus coruscus Hydrolysate Using Uniform Design

Table 2

Uniform Design with the observed responses and predicted values.

Treat	Variable levels				Experimental 𝑌𝑒	Predicted Y	LRE (%)
	𝑋1	𝑋2	𝑋3	𝑋4
1	25	2	7.0	60	87.98±3.14	88.08	4.8
2	50	4	8.5	55	77.21±2.18	77.49	3.7
3	75	6	6.5	50	36.92±1.91	36.83	5.0
4	100	1	8.0	45	26.54±1.47	26.28	2.1
5	125	3	6.0	40	39.46±2.31	39.02	3.6
6	150	5	7.5	35	58.13±2.35	58.47	4.4
7	175	7	9.0	65	20.17±1.17	20.46	3.2

𝑋₁: protease concentration, U/mL; 𝑋₂: hydrolysis time, h; 𝑋₃: hydrolysis pH; 𝑋₄: hydrolysis temperature, °C; experimental 𝑌_𝑒 was expressed as mean ± standard deviation of three determinations; LRE: largest relative error = 100×|thelargestorthelowest𝑌_𝑒−𝑌|/average 𝑌_𝑒.