Table 2.
Changes in some physicochemical and microbiological properties of yogurt samples
| Properties | Storage period (day) | Yogurt samples | ||
|---|---|---|---|---|
| C | HM15 | HM20 | ||
| pH | 1 | 4.31 ± 0.00a, A | 4.07 ± 0.00b, A | 3.95 ± 0.01c, A |
| 7 | 4.25 ± 0.01a, B | 4.03 ± 0.01b, B | 3.91 ± 0.01c, B | |
| 14 | 4.20 ± 0.01a, C | 4.03 ± 0.01b, B | 3.87 ± 0.01c, C | |
| 21 | 4.16 ± 0.01a, D | 3.99 ± 0.00b, C | 3.84 ± 0.01c, D | |
| Titratable acidity (%) | 1 | 1,00 ± 0.02c, C | 1.05 ± 0.00b, B | 1.08 ± 0.01a, D |
| 7 | 1.04 ± 0.01c, B | 1.06 ± 0.01b, B | 1.10 ± 0.01a, C | |
| 14 | 1.07 ± 0.02b, A | 1.08 ± 0.01b, A | 1.13 ± 0.01a, B | |
| 21 | 1.08 ± 0.01b, A | 1.08 ± 0.01b, A | 1.15 ± 0.01a, A | |
| Total solid (%) | 1 | 14.91 ± 0.33c, A | 22.27 ± 0.60b, A | 24.40 ± 0.09a, AB |
| 7 | 15.11 ± 0.37c, A | 22.16 ± 0.14b, A | 24.54 ± 0.43a, A | |
| 14 | 14.77 ± 0.34c, A | 21.65 ± 0.56b, AB | 23.80 ± 0.52a, B | |
| 21 | 15.30 ± 0.61c, A | 21.39 ± 0.26b, B | 23.06 ± 0.42a, C | |
| Fat (%) | 1 | 3.06 ± 0.06a, AB | 2.68 ± 0.07b, A | 2.48 ± 0.01c, AB |
| 7 | 3.10 ± 0.08a, AB | 2.61 ± 0.02b, AB | 2.52 ± 0.05b, A | |
| 14 | 2.97 ± 0.07a, B | 2.53 ± 0.07b, B | 2.43 ± 0.05b, B | |
| 21 | 3.20 ± 0.13a, A | 2.61 ± 0.03b, AB | 2.43 ± 0.05c, B | |
| Protein (%) | 1 | 3.38 ± 0.19a, B | 3.31 ± 0.04b, A | 2.76 ± 0.58c, D |
| 7 | 3.82 ± 0.16a, A | 3.15 ± 0.03b, B | 2.96 ± 0.01c, C | |
| 14 | 3.79 ± 0.08a, A | 3.44 ± 0.01b, A | 3.19 ± 0.02c, B | |
| 21 | 3.52 ± 0.04a, B | 3.13 ± 0.06b, B | 3,00 ± 0.08c, A | |
| Ash (%) | 1 | 0.624 ± 0.01c, A | 0.651 ± 0.03b, A | 0.683 ± 0.01a, A |
| 7 | 0.623 ± 0.00c, A | 0.657 ± 0.01b, A | 0.676 ± 0.01a, A | |
| 14 | 0.627 ± 0.05c, A | 0.651 ± 0.05b, A | 0.677 ± 0.02a, A | |
| 21 | 0.631 ± 0.01c, A | 0.642 ± 0.02b, A | 0.682 ± 0.00a, A | |
| SPC | 1 | 8.91 ± 0.02a, A | 8.37 ± 0.11b, A | 8.29 ± 0.01b, A |
| 7 | 8.76 ± 0.01a, B | 8.27 ± 0.01b, B | 8.26 ± 0.03b, AB | |
| 14 | 8.35 ± 0.08b, C | 8.23 ± 0.01ab, B | 8.12 ± 0.14b, B | |
| 21 | 8.20 ± 0.06a, D | 7.33 ± 0.01b, C | 7.22 ± 0.12b, C | |
| LAB | 1 | 9.05 ± 0.01a, A | 8.89 ± 0.11b, A | 8.83 ± 0.04b, A |
| 7 | 8.99 ± 0.09a, A | 8.75 ± 0.03b, B | 8.58 ± 0.09c, B | |
| 14 | 8.65 ± 0.30a, B | 8.59 ± 0.06a, C | 8.17 ± 0.10b, C | |
| 21 | 8.50 ± 0.01a, B | 7.97 ± 0.03b, D | 7.90 ± 0.04c, D | |
*Different lower letters (between samples at the same storage day) in the same column and different capital letters (during storage days) in the same line indicate significant differences (p < 0,01)