Table 1.

Independent and response variables in the Box-Behnken design for the optimization of the formulation of microcapsules

Independent variable	Level			Response variable	Constraint
	Low (−1)	Medium (0)	High (1)
A=ALG concentration (%, 1%=10 g/L)	1.4	1.6	1.8	EE (%)	Maximize
B=COS concentration (%, 1%=10 g/L)	0.0	0.5	1.0	LC (%)	Maximize
C=IgY/ALG ratio (%, mass ratio)	31.25	50.00	68.75	APS (μm)	Minimize

ALG: alginate; COS: chitooligosaccharide; IgY: immunoglobulin Y; EE: encapsulation efficiency; LC: loading capacity; APS: average particle size