The evolution of antioxidative properties of protein-derived peptides of Mexican Panela goat and cow milk cheese during its shelf life

Figures & data

Table 1. Physicochemical parameters of cow’s and goat’s milk (raw material).

Parameter	Cow´s milk	Goat´s milk
Fat (%)	2.45 ± 0.04^A	3.87 ± 0.02^B
Non-fat Solids (%)	8.01 ± 0.01^A	7.48 ± 0.028^B
Density (kg/m^3)	1028.19 ± 0.08^A	1026.05 ± 0.13^B
Lactose (%)	4.40 ± 0.01^A	3.34 ± 0.01^B
Proteins (%)	2.93 ± 0.01^A	3.54 ± 0.01^B
Total solids (%)	10.46 ± 0.04^A	11.36 ± 0.01^B
Freezing point (ºC)	−0.50 ± 0.00^A	−0.41 ± 0.00^B
Electrict conductivity (mS/cm)	5.76 ± 0.27^A	5.05 ± 0.01^B

The results were expressed as a mean value with standard deviation. ^A,BDifferent literals indicate significant differences (p < .01) between parameters by type of milk.

Figure 1. Sensory acceptance of attributes (flavor, texture and acidity) in Panela cheeses made from cow’s milk (black) and goat’s milk (gray). With standard error bars. There are no significant differences because of cheese type between attributes (p > .01).

Table 2. Titratable acidity (° Dornic) during shelf life in Panela cheese made with cow’s and goat’s milk.

Monitoring day	Cow´s milk Panela cheese	Goat´s milk Panela cheese
Day 1	12.33 ± 0.57^Bd	11.33 ± 1.15^Ad
Day 7	14.33 ± 0.57^Bd	14.00 ± 2.00^Ad
Day 14	17.00 ± 2.00^Bc	28.33 ± 5.77^Ac
Day 21	29.66 ± 4.72^Bb	63.00 ± 2.64^Ab
Day 28	47.33 ± 6.80^Ba	67.00 ± 2.00^Aa

The results were expressed as a mean value with standard deviation. ^A,BDifferent literals in the same row indicate significant differences in the samples (p < .01) due to the effect of milk type. ^a,b,c,d Different literals in the same column indicate significant differences in the samples (p < .01) due to the effect of monitoring day.

Table 3. Proteolytic activity (%) in water-soluble peptides extract of Panela cheese made with cow´s and goat´s milk.

Monitoring day	Cow´s milk Panela cheese	Goat´s milk Panela cheese
Day 1	1.68 ± 0.64^Bc	4.51 ± 0.67^Ad
Day 7	3.10 ± 0.85^Bc	6.41 ± 0.32^Ac
Day 14	6.00 ± 1.79^Bb	8.32 ± 0.54^Ab
Day 21	9.47 ± 1.23^Ba	9.09 ± 0.02^Aa
Day 28	10.57 ± 2.98^Ba	9.19 ± 0.26^Aa

The results were expressed as a mean value with standard deviation. ^A,BDifferent literals in the same row indicate significant differences in the samples (p < .01) due to the effect of milk type. ^a,b,c,d Different literals in the same column indicate significant differences in the samples (p < .01) due to the effect of monitoring day.

Table 4. Peptide concentration (mg/mL) in water-soluble peptides extract of Panela cheese made with cow´s and goat´s milk.

Monitoring day	Cow´s milk Panela cheese	Goat´s milk Panela cheese
Day 1	0.07 ± 0.03^Bd	0.24 ± 0.03^Ad
Day 7	0.14 ± 0.01^Bc	0.20 ± 0.01^Ac
Day 14	0.25 ± 0.01^Ba	0.24 ± 0.03^Aa
Day 21	0.23 ± 0.01^Bb	0.19 ± 0.01^Ab
Day 28	0.21 ± 0.01^Bc	0.16 ± 0.01^Ac

The results were expressed as a mean value with standard deviation. ^A,BDifferent literals in the same row indicate significant differences in the samples (p < .01) due to the effect of milk type. ^a,b,c,d Different literals in the same column indicate significant differences in the samples (p < .01) due to the effect of monitoring day.

Table 5. Antioxidant activity in water-soluble peptides extract of Panela cheese made with cow´s and goat´s milk, with two different concentrations of the DPPH reagent.

Monitoring day	Cow´s milk Panela cheese^B		Goat´s milk Panela cheese^A
	Concentration 1 (0.04 mM)	Concentration 2 (0.06 mM)	Concentration 1 (0.04 mM)	Concentration 2 (0.06 mM)
Day 1	28.33 ± 6.40^a1	15.99 ± 5.44^a2	79.71 ± 3.41^a1	69.11 ± 2.88^a2
Day 7	34.98 ± 19.81^b1	13.99 ± 5.70^b2	74.12 ± 7.59^b1	25.66 ± 14.08^b2
Day 14	32.22 ± 19.53^a1	29.71 ± 6.33^a2	64.80 ± 8.66^a1	59.12 ± 5.10^a2
Day 21	20.91 ± 10.16^ab1	30.65 ± 9.68^ab2	63.76 ± 11.14^ab1	56.76 ± 3.66^ab2
Day 28	22.75 ± 7.37^ab1	24.43 ± 15.82^ab2	63.09 ± 8.07^ab1	60.90 ± 7.21^ab2

The results were expressed as a mean value with standard deviation. ^{A, B,} Different literals indicate significant differences in the samples (p < .01) due to the effect of milk type. ^{a, b, c, d,} Different literals in the same column indicate significant differences in the samples (p < .01) due to the effect of monitoring day. ^1,2 Different numbers in the same row indicate significant differences in the samples (p < .01) due to the effect of DPPH reagent concentration.

Figure 2. Loading plots from the Principal Component Analysis (PCA) carried out on all variables at day 1 of shelf life (proteolysis, peptide concentration, and antioxidant activity). 1: cheeses with cow’s milk and 2: cheeses with goat´s milk. Prin: Principal Component. Figure obtained statistical package Statistical Analysis System (SAS, 2016).

Table 6. Pearson correlation coefficients in water-soluble peptides extract of Panela cheese made with cow´s and goat´s milk.

Variables	Proteolytic activity	Peptide concentration	Antioxidant activity
Proteolytic activity	1.000	0.93043 <0.0001	0.95450 <0.0001
Peptide concentration	0.93043 <0.0001	1.000	0.92450 <0.0001
Antioxidant activity	0.95450 <0.0001	0.92450 <0.0001	1.000

Statistical Analysis System. (2016). SAS 9.4 TS1M3. for Windows. SAS Institute Inc.

 Google Scholar