Development of a Novel Whey Date Beverage Fermented with Kefir Grains Using Response Surface Methodology

Table 4

Analysis of variance as a linear, quadratic, and interaction for each response variable.

	Coefficient	Standard deviation	t.exp	Signif. %	Coefficient	Standard deviation	t.exp	Signif. %
	pH				LAB (log10 CFU/mL)
b0	4.175	0.024	175.17		3.796	0.144	26.44
b1	0.093	0.014	6.43		−0.426	0.087	−4.90
b2	0.165	0.014	11.43		−0.688	0.087	−7.92
b3	−0.059	0.014	−4.10		−1.144	0.087	−13.15
b11	0.019	0.014	1.32	21.7	−0.218	0.087	−2.51
b22	0.051	0.014	3.53		0.259	0.087	2.98
b33	0.024	0.014	1.69	12.3	1.092	0.087	12.55
b12	0.004	0.019	0.20	84.1	0.807	0.114	7.11
b13	0.044	0.019	2.32		−0.467	0.114	−4.11
b23	−0.079	0.019	−4.17		−0.613	0.114	−5.39
	Yeasts (log10 CFU/mL)				DPPH scavenging activity (%)
b0	3.434	0.043	80.07		90.914	0.110	826.23
b1	−0.317	0.026	−12.19		−1.630	0.067	−24.45
b2	−0.417	0.026	−16.06		0.108	0.067	1.62	18.0
b3	−0.559	0.026	−21.51		1.083	0.067	16.24
b11	−0.342	0.026	−13.15		−1.384	0.067	−20.75
b22	−0.110	0.026	−4.24		−1.060	0.067	−15.90
b33	0.956	0.026	36.77		−0.629	0.067	−9.43
b12	0.422	0.034	12.45		2.731	0.087	31.36
b13	−0.652	0.034	−19.22		3.036	0.087	34.86
b23	−0.460	0.034	−13.55		−2.856	0.087	−32.80
	Total phenolic content (mg/mL)				Overall acceptability (scores)
b0	24.179	0.374	64.70		3.664	0.051	71.95
b1	0.419	0.226	1.85	13.7	−0.117	0.031	−3.81
b2	10.358	0.226	45.75		1.073	0.031	34.77
b3	−8.993	0.226	−39.72		−0.231	0.031	−7.50
b11	6.409	0.226	28.30		0.397	0.031	12.88
b22	5.702	0.226	25.18		0.433	0.031	14.03
b33	7.117	0.226	31.43		0.786	0.031	25.48
b12	−0.875	0.296	−2.96		−0.138	0.040	−3.41
b13	−5.375	0.296	−18.17		0.037	0.040	0.93	40.7
b23	−6.875	0.296	−23.24		0.013	0.040	0.31	76.7

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