Table 5.
Comparison of the antibacterial effect of different concentrations of NE and NE-SSC on L. monocytogenes and E. coli O157:H7 in milk stored at 4 and 10°C.
| Bacteria | Temperature | Day | NE | NE-SCC | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0% | 3% | 7% | 10% | 0% | 3% | 7% | 10% | |||||
| p-value | p-value | |||||||||||
| L. monocytogenes | 4°C | 0 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 1 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 1 |
| 1 | 5.50 ± 0.06a | 5.48 ± 0.04a | 5.16 ± 0.08b | 4.92 ± 0.04c | < 0.001*** | 5.50 ± 0.06a | 5.39 ± 0.02a | 5.03 ± 0.16b | 4.63 ± 0.02c | < 0.001*** | ||
| 3 | 7.53 ± 0.05a | 7.38 ± 0.07a | 6.51 ± 0.03b | 5.45 ± 0.08c | < 0.001*** | 7.53 ± 0.05a | 7.02 ± 0.06b | 5.59 ± 0.02c | 5.00 ± 0.03d | < 0.001*** | ||
| 7 | 8.09 ± 0.04a | 8.06 ± 0.04a | 7.52 ± 0.18b | 6.88 ± 0.10c | < 0.001*** | 8.09 ± 0.04a | 8.13 ± 0.06a | 7.14 ± 0.10b | 5.46 ± 0.09c | < 0.001*** | ||
| 10°C | 0 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 1 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 4.41 ± 0.06 | 1 | |
| 1 | 6.07 ± 0.11a | 5.58 ± 0.07b | 5.30 ± 0.02c | 5.04 ± 0.03d | < 0.001*** | 6.07 ± 0.11a | 5.26 ± 0.05b | 4.68 ± 0.01c | 4.58 ± 0.05c | < 0.001*** | ||
| 3 | 7.79 ± 0.12a | 7.33 ± 0.12b | 6.43 ± 0.08c | 5.90 ± 0.20d | < 0.001*** | 7.79 ± 0.12a | 7.12 ± 0.08b | 5.56 ± 0.14c | 5.11 ± 0.05d | < 0.001*** | ||
| 7 | 8.04 ± 0.02b | 8.24 ± 0.05a | 7.92 ± 0.04b | 7.46 ± 0.03c | < 0.001*** | 8.04 ± 0.02a | 8.21 ± 0.11a | 7.61 ± 0.07b | 6.23 ± 0.05c | < 0.001*** | ||
| E. coli O157:H7 | 4°C | 0 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 1 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 1 |
| 1 | 4.37 ± 0.05 | 4.44 ± 0.12 | 4.15 ± 0.16 | 4.10 ± 0.06 | 0.124 | 4.37 ± 0.05 | 4.34 ± 0.11 | 4.15 ± 0.17 | 3.89 ± 0.22 | 0.173 | ||
| 3 | 6.02 ± 0.04a | 5.69 ± 0.11b | 4.87 ± 0.08c | 4.48 ± 0.10d | < 0.001*** | 6.02 ± 0.04a | 5.60 ± 0.00b | 4.76 ± 0.03c | 4.14 ± 0.04d | < 0.001*** | ||
| 7 | 7.66 ± 0.03a | 8.09 ± 0.21a | 5.47 ± 0.54b | 4.25 ± 0.01c | < 0.001*** | 7.66 ± 0.03a | 7.58 ± 0.04a | 5.24 ± 0.26b | 3.72 ± 0.07c | < 0.001*** | ||
| 10°C | 0 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 1 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 3.99 ± 0.02 | 1 | |
| 1 | 5.11 ± 0.06a | 4.73 ± 0.04b | 4.33 ± 0.03c | 4.12 ± 0.07d | < 0.001*** | 5.11 ± 0.06a | 3.92 ± 0.26b | 3.57 ± 0.16b | 3.99 ± 0.05b | < 0.001*** | ||
| 3 | 7.05 ± 0.06a | 6.95 ± 0.03a | 5.85 ± 0.00b | 4.45 ± 0.03c | < 0.001*** | 7.05 ± 0.06a | 6.67 ± 0.05b | 4.87 ± 0.03c | 4.27 ± 0.05d | < 0.001*** | ||
| 7 | 8.87 ± 0.02a | 8.54 ± 0.11b | 8.01 ± 0.04c | 5.11 ± 0.06d | < 0.001*** | 8.87 ± 0.02a | 8.23 ± 0.01b | 5.20 ± 0.10c | 4.14 ± 0.07d | < 0.001*** | ||
Values are means (log10 CFU/ml) of three experiments ± SEM.
Means within row not sharing a similar superscript differ significantly (*p < 0.05, **p < 0.01, and ***p < 0.001, where *, **, and *** denote levels of significance difference).
Row-wise comparisons were performed using ANOVA with DMRT post-hoc.