Table 4.
Effect of HTST pasteurization process and storage time (at 4°C) on protein composition (±SD) of goat milk.
ST$ | Milk | HTST pasteurization treatments (temperature-time) | |||||
---|---|---|---|---|---|---|---|
Protein | 72°C | 75°C | 81°C | ||||
15 s | 25 s | 15 s | 25 s | 15 s | 25 s | ||
0∗ | Casein (w/w%) | 2.64 ± 0.05 | 2.64 ± 0.07 | 2.63 ± 0.14 | 2.65 ± 0.22 | 2.64 ± 0.1 | 2.62 ± 0.52 |
Whey protein (TP%)† | 17.28 | 17.00 | 17.28 | 17.00 | 15.80 | 14.91 | |
WPD (%)‡ | 0 | 0 | 0 | 1.63 | 8.23 | 13.45 | |
2 | Casein (w/w%) | 2.61 ± 0.02 | 2.59 ± 0.01 | 2.56 ± 0.03 | 2.58 ± 0.01 | 2.48 ± 0.01 | 2.48 ± 0.00 |
Whey protein (TP%) | 17.70 | 16.52 | 16.42 | 14.84 | 15.29 | 13.17 | |
WPD (%) | 0 | 4.11 | 4.70 | 14.00 | 11.26 | 23.60 | |
3 | Casein (w/w%) | 2.48 ± 0.02 | 2.5 ± 0.1 | 2.49 ± 0.1 | 2.49 ± 0.01 | 2.45 ± 0.03 | 2.43 ± 0.02 |
Whey protein (TP%) | 15.85 | 14.73 | 14.46 | 14.46 | 13.56 | 11.94 | |
WPD (% ) | 8.00 | 14.54 | 16.07 | 16.07 | 21.27 | 30.73 | |
4 | Casein (w/w%) | 2.48 ± 0.01 | 2.45 ± 0.01 | 2.43 ± 0.01 | 2.45 ± 0.01 | 2.24 ± 0.02 | 2.32 ± 0.02 |
Whey protein (TP%) | 11.50 | 11.25 | 11.61 | 11.00 | 11.80 | 8.04 | |
WPD (%) | 33.03 | 34.68 | 32.60 | 36.35 | 31.48 | 53.33 |
$ST = Storage time (weeks) at 4°C; †Whey protein (TP%) = Whey protein as % total protein; ‡WPD = Whey protein denatured (%); ∗0 = immediately after pasteurization (IAP).