Table 2.

Regression equations for cakes with different formulations baked during different baking times in combination oven

Quality parameter	Equation	r 2	Lack of fit
Weight loss	Y1 = 27.2833*** − 0.6936**X1 − 0.4263* X 2 + 2.6026***X3 − 0.9962**X1 2 − 1.0384** X2 2 − 1.2487** X3 2 − 0.1037nsX1X2 + 0.3010ns X1X3 − 0.0262ns X2X3	96.91	0.267ns
Total color change	Y1 = 58.3728*** + 1.6641***X1 + 0.0716nsX2 + 3.9558***X3 − 0.5407*X1 2 + 0.1550ns X2 2 + 1.8106*** X3 2 + 0.1075nsX1X2 + 0.0533ns X1X3 − 0.3022ns X2X3	99.11	0.594ns
Specific volume	Y1 = 1.30497*** − 0.04634**X1 + 0.02243* X 2 + 0.09863***X3 − 0.05883**X1 2 − 0.06608** X2 2 − 0.02389ns X3 2 − 0.00014nsX1X2 + 0.01725ns X1X3 + 0.00500ns X2X3	93.32	6.49ns
Hardness	Y1 = 0.1528*** + 0.0090nsX1 − 0.0137* X 2 + 0.0395***X3 + 0.0035nsX1 2 − 0.0099ns X2 2 + 0.0036ns X3 2 − 0.0109nsX1X2 + 0.0097ns X1X3 − 0.0029ns X2X3	85.51	15.65ns

*The term is significant at p ≤ 0.05

**The term is significant at p ≤ 0.01

***The term is significant at p ≤ 0.001