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

Table 2

Matrix of the central composite design for three variables and the measured responses (DPPH scavenging activity and total phenolic content).

Run	Independent variables			Response variables
	X1 (whey permeate, % w/v)	X2 (myrte juice, % w/v)	X3 (kefir grains, % w/v)	DPPH scavenging activity (%)	Total phenolic content (mg EGA/mL)
1	1.0	18	2.6	68.40 ± 0.61	57.58 ± 0.28
2	4.0	18	2.6	72.60 ± 0.26	59.75 ± 0.42
3	1.0	42	2.6	71.25 ± 0.36	64.80 ± 0.49
4	4.0	42	2.6	75.60 ± 0.26	63.60 ± 1.04
5	1.0	18	4.4	70.80 ± 0.06	69.97 ± 0.08
6	4.0	18	4.4	73.60 ± 0.30	70.68 ± 0.29
7	1.0	42	4.4	91.36 ± 0.13	85.00 ± 0.04
8	4.0	42	4.4	95.95 ± 0.38	89.45 ± 0.39
9	−0.0	30	3.5	80.45 ± 0.03	82.20 ± 0.91
10	5.0	30	3.5	85.62 ± 0.01	81.69 ± 0.14
11	2.5	10	3.5	69.80 ± 0.04	55.25 ± 0.68
12	2.5	50	3.5	91.60 ± 0.29	90.45 ± 0.07
13	2.5	30	2.0	65.25 ± 0.22	69.30 ± 0.26
14	2.5	30	5.0	89.85 ± 0.20	81.20 ± 0.42
15	2.5	30	3.5	71.50 ± 0.44	63.10 ± 0.13
16	2.5	30	3.5	72.05 ± 0.15	62.50 ± 0.14
17	2.5	30	3.5	71.95 ± 0.43	63.01 ± 0.026
18	2.5	30	3.5	72.42 ± 0.02	62.90 ± 0.35
19	2.5	30	3.5	71.15 ± 0.38	63.05 ± 0.39