Table 3.

ANOVA for response surface quadratic model^a

Source	Sum of squares	df	Mean square	F value	p-Value Prob > F
Modelb	0.15	9	0.016	45.83	<0.0001	Significant
X 1	0.022	1	0.022	61.62	0.0001	Significant
X 2	0.001512	1	0.001512	4.23	0.0788
X 3	0.002812	1	0.002812	7.86	0.0264	Significant
X 1 X 2	0.002025	1	0.002025	5.66	0.0490	Significant
X 1 X 3	0.038	1	0.038	106.26	<0.0001	Significant
X 2 X 3	0.0004	1	0.0004	1.12	0.3255
X 1 2	0.011	1	0.011	31.21	0.0008	Significant
X 2 2	0.062	1	0.062	172.27	<0.0001	Significant
X 3 2	0.008909	1	0.008909	24.90	0.0016	Significant
Residual	0.002505	7	0.0003579
Lack of fit	0.001825	3	0.0006083	3.58	0.1249	not Significant
Pure error	0.00068	4	0.00017
Cor total	0.15	16

^aThe results were obtained with the Design Expert 8.0.5b software

^b X ₁ is milk layer thickness (cm). X ₂ is microwave time (s). X ₃ is microwave power (W)