The presence of some pathogen micro organisms, yeasts and moulds in cheese samples produced at small dairy-processing plants
The presence of pathogenic and some indicator micro organisms was studied in 40 samples of cheese comprising 14 curd samples, 13 samples of soft ripened salted or non-salted cheese and 13 samples of semi-hard cheese manufactured at five small dairy-processing plants. The mean number of coagulase-...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
University of Ljubljana Press (Založba Univerze v Ljubljani)
2006-11-01
|
| Series: | Acta Agriculturae Slovenica |
| Subjects: | |
| Online Access: | https://journals.uni-lj.si/aas/article/view/15059 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | The presence of pathogenic and some indicator micro organisms was studied in 40 samples of
cheese comprising 14 curd samples, 13 samples of soft ripened salted or non-salted cheese and
13 samples of semi-hard cheese manufactured at five small dairy-processing plants. The mean
number of coagulase-positive staphylococci in all tested samples was 2.5 × 104
cfu*
g–1
, while
the number of E. coli bacteria was 1.4 × 106
cfu g–1
. In 20.0% out of 40 samples tested, the
number of coagulase-positive staphylococci exceeded the prescribed regulations, particularly in
soft cheese (12.5%) and curd (7.5%). About 17.5% of samples were contaminated with E. coli in
higher concentrations than national valid regulations allowed. The number of E. coli was mostly
exceeded in soft cheese and curd in 12.5% and 5.0% of all examined samples, respectively. One
sample of semi hard cheese was contaminated with sulphite-reducing clostridia. Proteus was
detected in 3 samples (7.5%) and L. grayi in 1 (2.5%) sample. Salmonela and L. monocytogenes
were not detected. According to the valid regulations 9 (22.5%) samples in our investigation did
not reach the adequate microbiological quality. Both, yeasts and moulds were isolated from 60% of tested cheese samples with average concentrations of 5.8 × 104 cfu g–1 and 2.0 × 104 cfu g–1, respectively. The genera Geotrichum (91.9%), Moniliella (5.4%) and Aspergillus (2.7%) were the most frequently isolated strains from examined cheese samples. The Aspergillus strains did not belong to the species A. flavus or A. parasiticus and did not produce aflatoxins. |
|---|---|
| ISSN: | 1854-1941 |