Table 5.
Microbial loads of samples collected during the artificial contamination test.
| Samples | Microbial Counts | |||||
|---|---|---|---|---|---|---|
| TMM | Lc. lactis | E. coli | L. monocytogenes | S. Enteritidis | St. aureus | |
| Pasteurized milk | 2.71 | 2.64 | <1 | <1 | <1 | <1 |
| Inoculated milk | ||||||
| CCP | 7.09 | 7.01 | 3.99 | 3.91 | 4.02 | 3.88 |
| ECPO100 | 7.13 | 7.06 | 3.86 | 3.82 | 3.97 | 3.80 |
| ECPO200 | 7.08 | 7.09 | 3.90 | 3.90 | 4.05 | 3.99 |
| SEM | 0.06 | 0.05 | 0.06 | 0.05 | 0.05 | 0.06 |
| p value | 0.972 | 0.914 | 0.829 | 0.865 | 0.928 | 0.673 |
| Curd | ||||||
| CCP | 7.96 | 7.95 | 4.90 | 4.82 | 4.79 | 5.01 |
| ECPO100 | 8.03 | 7.87 | 4.91 | 4.73 | 4.82 | 4.94 |
| ECPO200 | 8.01 | 7.92 | 4.84 | 4.66 | 4.76 | 5.05 |
| SEM | 0.05 | 0.04 | 0.05 | 0.06 | 0.04 | 0.04 |
| p value | 0.926 | 0.870 | 0.929 | 0.782 | 0.942 | 0.817 |
| Cheese | ||||||
| CCP | 8.85 | 8.67 | 5.71 a | 5.31 a | 5.09 a | 5.66 a |
| ECPO100 | 8.96 | 8.84 | 2.99 b | 2.55 b | 3.01 b | 3.11 b |
| ECPO200 | 8.90 | 8.70 | 2.74 b | 2.23 b | 2.93 b | 3.01 b |
| SEM | 0.05 | 0.06 | 0.34 | 0.35 | 0.25 | 0.31 |
| p value | 0.857 | 0.727 | <0.0001 | <0.0001 | <0.0001 | <0.0001 |
Units are Log CFU/mL for milk samples and Log CFU/g for curds and cheeses. Results indicate the mean values of six plate counts (carried out in triplicate for two independent productions). Data within a column followed by the same letter are not significantly different according to Tukey’s test. Abbreviations: TMM, total mesophilic microorganisms; Lc., Lactococcus; E., Escherichia; L., Listeria; S., Salmonella; St., Staphylococcus; CCP, control cheese product inoculated with the milk starter cultures (MSC); ECPO100, experimental cheese product inoculated with MSC + 100 μL/L of oregano essential oils (OEOs); ECPO200, experimental cheese product inoculated with MSC + 200 μL/L of OEOs.