Table 2.
Effect of OCHs and CH on pH and metabolism and content of L. bulgaricus in the fermented milk product at 17-days storing.
| Index | Concentration of OCHs and CH, % | ||||
|---|---|---|---|---|---|
| 0 (control) | 0.0025 | 0.005 | 0.0075 | 0.01 | |
| 25.4 kDa, 1% DD OCH (glucosamine monomers 140/mol OCH) | |||||
| pH | 3.80 ± 0.10A | 3.30 ± 0.10B | 3.66 ± 0.10A | 3.88 ± 0.10A | 4.35 ± 0.10B |
| LA content, mol/L | 0.121 ± 0.011A | 0,037 ± 0.001B | 0,017 ± 0.001C | 0,034 ± 0.002B | 0,015 ± 0.002C |
| The average rate of LA synthesis, mol/L/h | 7.3 × 10−3A, I | 2.2 × 10−3B, I | 1.0 × 10−3C, I | 2.0 × 10−3B, I | 0.9 × 10−3C, I |
| L. bulgaricus content, CFU/g | 3.73 × 103A, α | 2.28 × 102B, α | 2.46 × 102B, α | 3.89 × 103A, α | 4.65 × 104C, α |
| 45.3 kDa, 1.5% DD OCH (glucosamine monomers 248/mol OCH) | |||||
| pH | 3.82 ± 0.10A | 3.48 ± 0.10B | 3.61 ± 0.10B | 3.91 ± 0.10A | 3.96 ± 0.10A |
| LA content, mol/L | 0.116 ± 0.01A | 0.043 ± 0.001B | 0.048 ± 0.001B | 0.070 ± 0.001C | 0.063 ± 0.001C |
| The average rate of LA synthesis, mol/L/h | 6.8 × 10−3A, I | 2.5 × 10−3B, I | 2.8 × 10−3B, II | 4.1 × 10−3C, II | 3.7 × 10−3C, II |
| L. bulgaricus content, CFU/g | 3.71 × 103A, α | 2.6 × 102B, α | 2.56 × 102B, β | 3.49 × 103A, α | 4.89 × 104C, α |
| 350 kDa, 5% DD CH (glucosamine monomers 1850/mol CH) | |||||
| pH | 3.82 ± 0.1A | 3.85 ± 0.1A | 3.87 ± 0.1A | 3.96 ± 0.1A | 4.04 ± 0.1A |
| LA content, mol/L | 0.113 ± 0.01A | 0.102 ± 0.009B | 0.104 ± 0.009B | 0.072 ± 0.007C | 0.063 ± 0.005C |
| The average rate of LA synthesis, mol/L/h | 7.0 × 10−3A, I | 6.0 × 10−3B, II | 6.0 × 10−3B, III | 4.2 × 10−3C, II | 3.7 × 10−3C, II |
| L. bulgaricus content, CFU/g | 3.69 × 103A, α | 3.65 × 103A, β | 3.59 × 103A, γ | 5.3 × 105B, β | 6.34 × 106C, β |
The values represent the mean ± SD (n = 3). Means without a common letter within the same column (I–III; α-γ) and row (A–C) indicate significant difference at p <0.05.