Optimization of Parameters Using Response Surface Methodology to Develop a Novel Kefir-Like Functional Beverage from Cheese Whey Enriched with Myrtle Juice

Table 3

Matrix of the central composite design for three variables and the measured responses (LAB viability, yeast viability, pH, and overall acceptability).

Run	Independent variables			Response variables		pH	Overall acceptability
	X1 (whey permeate, % w/v)	X2 (myrte juice, % w/v)	X3 (kefir grains, % w/v)	LAB viability (log10 CFU/mL)	Yeast viability (log10 CFU/mL)
1	1.0	18	2.6	6.28 ± 0.06	4.15 ± 0.01	5.02 ± 0.01	3.90 ± 0.10
2	4.0	18	2.6	6.80 ± 0.06	4.61 ± 0.06	4.88 ± 0.02	4.90 ± 0.20
3	1.0	42	2.6	6.02 ± 0.03	4.85 ± 0.02	4.78 ± 0.06	4.90 ± 0.10
4	4.0	42	2.6	7.39 ± 0.04	5.68 ± 0.09	4.69 ± 0.04	4.40 ± 0.10
5	1.0	18	4.4	6.98 ± 0.04	5.50 ± 0.07	4.45 ± 0.05	4.10 ± 0.20
6	4.0	18	4.4	7.09 ± 0.02	5.17 ± 0.04	4.41 ± 0.04	4.60 ± 0.10
7	1.0	42	4.4	7.10 ± 0.02	5.11 ± 0.03	4.36 ± 0.03	5.60 ± 0.10
8	4.0	42	4.4	9.23 ± 0.03	6.21 ± 0.07	4.21 ± 0.03	5.10 ± 0.20
9	−0.0	30	3.5	5.47 ± 0.09	4.79 ± 0.01	4.54 ± 0.04	4.90 ± 0.10
10	5.0	30	3.5	8.25 ± 0.04	6.02 ± 0.01	4.39 ± 0.03	4.10 ± 0.00
11	2.5	10	3.5	7.90 ± 0.02	5.19 ± 0.03	4.41 ± 0.05	4.70 ± 0.10
12	2.5	50	3.5	8.30 ± 0.03	5.90 ± 0.06	4.19 ± 0.04	5.60 ± 0.26
13	2.5	30	2.0	6.83 ± 0.06	4.39 ± 0.03	4.65 ± 0.01	4.60 ± 0.10
14	2.5	30	5.0	8.67 ± 0.04	5.29 ± 0.04	3.94 ± 0.05	4.50 ± 0.00
15	2.5	30	3.5	7.60 ± 0.07	5.10 ± 0.02	4.35 ± 0.03	4.40 ± 0.36
16	2.5	30	3.5	7.60 ± 0.03	5.31 ± 0.03	4.31 ± 0.02	3.40 ± 0.10
17	2.5	30	3.5	7.41 ± 0.04	5.25 ± 0.03	4.29 ± 0.08	4.10 ± 0.10
18	2.5	30	3.5	7.70 ± 0.03	5.19 ± 0.06	4.30 ± 0.02	3.95 ± 0.05
19	2.5	30	3.5	7.67 ± 0.02	5.26 ± 0.04	4.29 ± 0.02	4.05 ± 0.35

Overall acceptability score (9-point hedonic scale).