Table 1.
Microbial populations (log cfu/g) of total aerobic counts, enterobacteria, yeasts & fungi, lactococci and lactobacilli in Feta-type cheeses during 60 days of ripening and 30 days of storage at 4 °C.
| Time (days) | C1 | C2 | C3 | C4 | C5 | |
|---|---|---|---|---|---|---|
| TBC (log cfu/g) |
1 | 7.1 ± 0.1 a | 7.7 ± 0.2 b | 8 ± 0.1 bc | 8.57 ± 0.06 d | 8.27 ± 0.25 cd |
| 5 | 8.4 ± 0.1 a | 7.67 ± 0.06 b | 8.3 ± 0.1 a | 8.2 ± 0.2 a | 8.2 ± 0.2 a | |
| 10 | 8.33 ± 0.06 a | 8.23 ± 0.06 a | 7.9 ± 0.1 b | 8.03 ± 0.06 b | 8.53 ± 0.06 c | |
| 15 | 8.83 ± 0.06 a | 7.8 ± 0.1 b | 7.47 ± 0.06 c | 8.1 ± 0.1 d | 8.23 ± 0.06 d | |
| 30 | 8.37 ± 0.21 a | 8.13 ± 0.15 ab | 7.87 ± 0.06 bc | 7.67 ± 0.06 c | 7.73 ± 0.06 c | |
| 45 | 8.1 ± 0.1 a | 7.9 ± 0.1 ab | 7.7 ± 0.1 bc | 7.6 ± 0 bc | 7.5 ± 0.2 c | |
| 55 | 8 ± 0.1 a | 7.5 ± 0.2 b | 7.37 ± 0.06 bd | 6.33 ± 0.06 c | 7.17 ± 0.06 d | |
| 60 | 7.4 ± 0.2 a | 6.87 ± 0.06 b | 6.77 ± 0.06 b | 5.6 ± 0.1 c | 6.67 ± 0.06 b | |
| 75 | 7.03 ± 0.06 a | 6.5 ± 0.17 b | 6.67 ± 0.12 b | 5.23 ± 0.15 c | 6.1 ± 0.1 d | |
| 90 | 6.67 ± 0.06 a | 6.7 ± 0.1 a | 6.13 ± 0.06 b | 4.63 ± 0.31 c | 5.8 ± 0.1 b | |
| Count of Lactobacillus genus bacteria (log cfu/g) | 1 | 5.23 ± 0.15 a | 8.1 ± 0.1 b | 7.63 ± 0.06 c | 8.5 ± 0.1 d | 8.2 ± 0.1 b |
| 5 | 5.9 ± 0.1 a | 8.3 ± 0.1 b | 8.13 ± 0.15 b | 8.7 ± 0.1 c | 8.63 ± 0.06 c | |
| 10 | 6.1 ± 0.1 a | 8.6 ± 0.1 bc | 8.3 ± 0.1 b | 8.8 ± 0.2 c | 8.5 ± 0.1 bc | |
| 15 | 6.2 ± 0.1 a | 8.5 ± 0.1 bc | 8.4 ± 0.1 b | 8.6 ± 0.1 bc | 8.7 ± 0.1 c | |
| 30 | 5.7 ± 0.3 a | 8.6 ± 0.2 b | 7.9 ± 0.1 c | 8.6 ± 0.1 b | 8.5 ± 0.1 b | |
| 45 | 5.4 ± 0.1 a | 8.7 ± 0.1 b | 8.03 ± 0.06 c | 8.37 ± 0.06 d | 8.3 ± 0.1 d | |
| 55 | 5.47 ± 0.06 a | 8.17 ± 0.06 bc | 7.7 ± 0.1 d | 8.33 ± 0.06 c | 8.03 ± 0.06 b | |
| 60 | 5.2 ± 0.1 a | 7.7 ± 0.1 b | 7.5 ± 0.1 b | 8.5 ± 0.1 c | 7.7 ± 0.1 b | |
| 75 | 4.67 ± 0.15 a | 7.4 ± 0.1 b | 7.2 ± 0.2 b | 8.03 ± 0.06 c | 7.5 ± 0.1 b | |
| 90 | 4.2 ± 0.2 a | 7.1 ± 0.1 b | 6.7 ± 0.1 c | 7.7 ± 0.1 d | 7.1 ± 0.2 b | |
| Count of Lactococcus genus bacteria (log cfu/g) | 1 | 7.7 ± 0.2 a | 7.3 ± 0.2 b | 7.6 ± 0.1 ab | 6.7 ± 0.1 c | 7.7 ± 0.1 a |
| 5 | 8.2 ± 0.1 a | 7.7 ± 0.1 b | 7.4 ± 0.2 b | 6.4 ± 0.1 c | 7.4 ± 0.1 b | |
| 10 | 7.9 ± 0.1 a | 7.5 ± 0.1 b | 6.73 ± 0.06 c | 6.2 ± 0.1 d | 7.6 ± 0.1 b | |
| 15 | 7.6 ± 0.2 a | 7.8 ± 0.1 a | 6.3 ± 0.1 b | 5.9 ± 0.1 c | 7.2 ± 0.1 d | |
| 30 | 7.5 ± 0.1 a | 6.6 ± 0.1 b | 6.4 ± 0.1 b | 5.9 ± 0.1 c | 6.6 ± 0.1 b | |
| 45 | 7.7 ± 0.1 a | 6.8 ± 0.1 b | 6.4 ± 0.1 c | 4.6 ± 0.2 d | 5.27 ± 0.06 e | |
| 55 | 7.4 ± 0.1 a | 6.1 ± 0.1 b | 4.97 ± 0.15 c | 4.1 ± 0.1 c | 4.73 ± 0.06 d | |
| 60 | 6.93 ± 0.06 a | 5.8 ± 0.2 b | 4.7 ± 0.1 c | 3.7 ± 0.1 d | 4.1 ± 0.1 e | |
| 75 | 6.5 ± 0.1 a | 5.5 ± 0.1 b | 4.1 ± 0.1 c | 3.2 ± 0.2 d | 3.7 ± 0.1 e | |
| 90 | 6.13 ± 0.06 a | 5.1 ± 0.1 b | 4 ± 0.2 c | 3 ± 0.1 d | 3.33 ± 0.06 e | |
| Count of Enterobacteriaceae family bacteria (log cfu/g) | 1 | 2.9 ± 0.1 a | 2.4 ± 0.2 b | 2.2 ± 0.2 bc | 1.9 ± 0.1 c | 2.4 ± 0.1 b |
| 5 | 4.8 ± 0.1 a | 2.2 ± 0.1 b | 2.27 ± 0.15 b | 2.3 ± 0.1 bc | 2.6 ± 0.1 c | |
| 10 | 5.3 ± 0.2 a | 3.6 ± 0.1 b | 2.7 ± 0.1 c | 1.6 ± 0.2 d | 2.9 ± 0.1 c | |
| 15 | 4.4 ± 0.2 a | 3.1 ± 0.1 b | 2 ± 0.2 c | 1.8 ± 0.2 c | 2.2 ± 0.4 c | |
| 30 | 4.1 ± 0.1 a | 2.7 ± 0.1 b | 2.27 ± 0.25 c | 1.03 ± 0.06 d | 1.6 ± 0.1 e | |
| 45 | 3.6 ± 0.1 a | 2.1 ± 0.1 b | 1.7 ± 0.1 c | nd | 1.07 ± 0.06 d | |
| 55 | 3.3 ± 0.1 a | 1.6 ± 0.1 b | 1.6 ± 0.1 b | nd | nd | |
| 60 | 2.8 ± 0.2 a | 1.3 ± 0.1 b | 1.3 ± 0.2 b | nd | nd | |
| 75 | 2.6 ± 0.1 | nd | nd | nd | ||
| 90 | 2.4 ± 0.1 | nd | nd | nd | nd | |
| Count of Yeasts & Fungi (log cfu/g) | 1 | 6.4 ± 0.1 a | 5.8 ± 0.2 b | 6.6 ± 0.1 a | 6.7 ± 0.1 a | 6.6 ± 0.1 a |
| 5 | 5.7 ± 0.1 a | 5.1 ± 0.1 b | 6.2 ± 0.1 c | 6.2 ± 0.1 c | 7.2 ± 0.2 d | |
| 10 | 6.1 ± 0.1 a | 5.3 ± 0.2 b | 5.7 ± 0.1 c | 6 ± 0.1 ac | 7 ± 0.1 d | |
| 15 | 5.8 ± 0.1 a | 5.2 ± 0.1 b | 6.1 ± 0.1 c | 6.03 ± 0.06 ac | 6.8 ± 0.1 d | |
| 30 | 5.6 ± 0.1 a | 4.8 ± 0.1 b | 5.4 ± 0.1 a | 5.7 ± 0.1 a | 6.2 ± 0.2 c | |
| 45 | 5.9 ± 0.2 a | 4.1 ± 0.1 b | 5.2 ± 0.1 c | 5.2 ± 0.1 c | 5.7 ± 0.1 a | |
| 55 | 6.2 ± 0.1 a | 4.1 ± 0.1 b | 4.9 ± 0.1 c | 5.03 ± 0.06 c | 5.1 ± 0.1 c | |
| 60 | 5.9 ± 0.1 a | 3.8 ± 0.2 b | 4.4 ± 0.2 c | 4.3 ± 0.1 c | 4.9 ± 0.1 d | |
| 75 | 5.4 ± 0.2 a | 3.4 ± 0.2 b | 4.2 ± 0.2 c | 3.6 ± 0.1 b | 4.6 ± 0.1 c | |
| 90 | 4.8 ± 0.1 a | 3.1 ± 0.1 b | 3.7 ± 0.1 b | 3.2 ± 0.1 c | 4.4 ± 0.1 d | |
| Count of Staphylococcus genus bacteria (log cfu/g) | 1 | 1.1 ± 0.1 a | 1.4 ± 0.2 b | 1.0 ± 0.0 a | 1.1 ± 0.1 ab | 1.2 ± 0.1 ab |
| 5 | 1.7 ± 0.1 ab | 1.3 ± 0.1 c | 1.3 ± 0.2 c | 1.4 ± 0.1 ac | 1.9 ± 0.1 b | |
| 10 | 1.4 ± 0.1 a | 1.1 ± 0.1 b | 1.4 ± 0.1 a | 1.1 ± 0.1 b | 1.7 ± 0.1 c | |
| 15 | 1.27 ± 0.25 ab | 1.0 ± 0.0 a | 1.6 ± 0.1 b | 1.0 ± 0.0 a | 2.1 ± 0.1 c | |
| 30 | 1.1 ± 0.1 a | nd | 1.2 ± 0.1 ac | 1.03 ± 0.06 a | 1.4 ± 0.1 c | |
| 45 | 1.0 ± 0.0 a | nd | 1.0 ± 0.0 a | nd | 1.1 ± 0.1 a | |
| 55 | 1.1 ± 0.1 a | nd | nd | nd | 1.0 ± 0.0 a | |
| 60 | 1.0 ± 0.0 | nd | nd | nd | nd | |
| 75 | 1.0 ± 0.0 | nd | nd | nd | nd | |
| 90 | 1.0 ± 0.0 | nd | nd | nd | nd |
* nd. viable cells not detected. * C1–commercial Feta cheese manufactured with rennin enzyme, C2–Feta-type cheese manufacture with free starter culture added prior rennin enzyme, C3–Feta-type cheese manufacture with immobilized starter culture added prior rennin enzyme, C4–Feta-type cheese manufacture with free starter culture added after rennin enzyme, C5–Feta-type cheese manufacture with immobilized starter culture added after rennin enzyme. a–e Similar superscript letters in each row indicates no difference between the mean microbial counts for samples C1 to C5 (ANOVA with Tukey’s HSD post hoc application at 95% confidence level).