Table 1.

The factors and levels of the orthogonal array design.

Trial No.	(A) Precipitation Pressure (MPa)	(B) Precipitation Temperature (°C)	(C) MG Concentration (mg/mL)	(D) Feeding Speed (mL/min)
1	10	35	5	4
2	15	43	23	7
3	20	51	41	10
4	25	59	59	13