The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makers

The microbiological quality of 98 samples taken at some critical control points during the milking and processing of 14 semi-hard cheese made from raw cow milk by individual Slovenian producers was studied. The sampling points were: swabs from cows’ udders, milking machines inner surfaces before and...

Full description

Bibliographic Details
Main Authors: Karmen GODIČ TORKAR, Slavica GOLC TEGER
Format: Article
Language:English
Published: University of Ljubljana Press (Založba Univerze v Ljubljani) 2004-12-01
Series:Acta Agriculturae Slovenica
Subjects:
Online Access:https://journals.uni-lj.si/aas/article/view/15424
_version_ 1826532180312981504
author Karmen GODIČ TORKAR
Slavica GOLC TEGER
author_facet Karmen GODIČ TORKAR
Slavica GOLC TEGER
author_sort Karmen GODIČ TORKAR
collection DOAJ
description The microbiological quality of 98 samples taken at some critical control points during the milking and processing of 14 semi-hard cheese made from raw cow milk by individual Slovenian producers was studied. The sampling points were: swabs from cows’ udders, milking machines inner surfaces before and after milking, fresh raw and mixed milk from vats, whey immediately after curdling, brine, cheese after one month of ripening and after the following month of being kept vacuum packed at 6 °C. The high number of micro-organisms on the inner surfaces of washed milking machines before milking revealed ineffective cleaning (washing) by about 60% of cheese producers. There were no seasonal differences in the number of micro-organisms, except that the number of coliforms was higher in spring. The average of total number of micro-organisms was 4.9·105 cfu/ml in raw milk and 5.5·106 cfu/ml in mixed milk from a vat (raw fresh milk mixed with milk kept for about 18–24 hours at room temperature), which did not grow significantly during cheese-processing. The number of coliforms in raw and mixed milk was in the range of 3.4·105 cfu/ml and fell to 5.4·104 cfu/ml in whey. The average number of enterococci, aerobic spore-forming micro-organisms, yeasts and moulds, lactobacilli, lactococci, proteolytic and lipolytic micro-organisms in milk and in whey were in the same logarithmic range of about 2.2·104, 310, 3.5, 31.2·104, 2.1·106, 6.2·103 and 1.7·104 cfu/ml of the sample, respectively. Listeria spp. was isolated from 5.3% (cows’ udders, milking machine, milk and whey), while none of the examined samples were positive to the presence of Salmonella spp. and Campylobacter spp. Proteus was present in 7 (7%) cases of milk and whey. Clostridia were detected in 10 (10%) samples (swabs, raw milk, whey). E. coli was isolated from 12 (12%) samples of swabs, raw and mixed milk, whey and brine. After one month of ripening the average total bacterial count was 9.2·107 cfu g–1 of cheese, of these 6.8·107 represented lactic-acid producers and 2.2·107 represented non-lactic acid producers. The average number of coliforms, enterococci, aerobic spore-forming micro-organisms, yeasts and moulds, lactococci, lactobacilli, proteolytic and lipolytic micro-organisms were 2.0·105, 6.3·106, 280, 960, 2.5·107, 9.8·107, 450 and 9.8·104 cfu g–1 of cheese, respectively. Salmonella spp., Listeria spp., Proteus, sulphite-reducing clostridia and Campylobacter spp. were not detected in cheese samples. E. coli was found in 4 (30%) of samples while coagulase positive staphylococci were present in 9 (64%) of cheese samples. A high number of enterococci (from a min. 3.103 to a max. 15.107 cfu g–1) and coliforms (from a min. 10 to a max. 19.105 cfu g–1) were detected as well. After one month of keeping vacuum-packed ripened cheeses at 6 °C, the number of micro-organisms did not rise significantly, except for the number of yeasts and moulds which grew to 3.6·104 cfu g–1 of cheese. Because of improper milking and processing hygiene conditions, three (21%) of the tested cheese samples did not correspond to the microbiological criteria according to the applicable regulations.
first_indexed 2024-03-08T23:22:58Z
format Article
id doaj.art-9d7ea29c3d894549921f01d78803b460
institution Directory Open Access Journal
issn 1854-1941
language English
last_indexed 2025-03-14T01:47:08Z
publishDate 2004-12-01
publisher University of Ljubljana Press (Založba Univerze v Ljubljani)
record_format Article
series Acta Agriculturae Slovenica
spelling doaj.art-9d7ea29c3d894549921f01d78803b4602025-03-12T12:22:22ZengUniversity of Ljubljana Press (Založba Univerze v Ljubljani)Acta Agriculturae Slovenica1854-19412004-12-01841436110.14720/aas.2004.84.1.1542421817The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makersKarmen GODIČ TORKAR0Slavica GOLC TEGER1Univ. of Ljubljana, Biotechnical Fac., Zootechnical Dept., Groblje 3, SI-1230 Domžale, SloveniaUniv. of Ljubljana, Biotechnical Fac., Zootechnical Dept., Groblje 3, SI-1230 Domžale, SloveniaThe microbiological quality of 98 samples taken at some critical control points during the milking and processing of 14 semi-hard cheese made from raw cow milk by individual Slovenian producers was studied. The sampling points were: swabs from cows’ udders, milking machines inner surfaces before and after milking, fresh raw and mixed milk from vats, whey immediately after curdling, brine, cheese after one month of ripening and after the following month of being kept vacuum packed at 6 °C. The high number of micro-organisms on the inner surfaces of washed milking machines before milking revealed ineffective cleaning (washing) by about 60% of cheese producers. There were no seasonal differences in the number of micro-organisms, except that the number of coliforms was higher in spring. The average of total number of micro-organisms was 4.9·105 cfu/ml in raw milk and 5.5·106 cfu/ml in mixed milk from a vat (raw fresh milk mixed with milk kept for about 18–24 hours at room temperature), which did not grow significantly during cheese-processing. The number of coliforms in raw and mixed milk was in the range of 3.4·105 cfu/ml and fell to 5.4·104 cfu/ml in whey. The average number of enterococci, aerobic spore-forming micro-organisms, yeasts and moulds, lactobacilli, lactococci, proteolytic and lipolytic micro-organisms in milk and in whey were in the same logarithmic range of about 2.2·104, 310, 3.5, 31.2·104, 2.1·106, 6.2·103 and 1.7·104 cfu/ml of the sample, respectively. Listeria spp. was isolated from 5.3% (cows’ udders, milking machine, milk and whey), while none of the examined samples were positive to the presence of Salmonella spp. and Campylobacter spp. Proteus was present in 7 (7%) cases of milk and whey. Clostridia were detected in 10 (10%) samples (swabs, raw milk, whey). E. coli was isolated from 12 (12%) samples of swabs, raw and mixed milk, whey and brine. After one month of ripening the average total bacterial count was 9.2·107 cfu g–1 of cheese, of these 6.8·107 represented lactic-acid producers and 2.2·107 represented non-lactic acid producers. The average number of coliforms, enterococci, aerobic spore-forming micro-organisms, yeasts and moulds, lactococci, lactobacilli, proteolytic and lipolytic micro-organisms were 2.0·105, 6.3·106, 280, 960, 2.5·107, 9.8·107, 450 and 9.8·104 cfu g–1 of cheese, respectively. Salmonella spp., Listeria spp., Proteus, sulphite-reducing clostridia and Campylobacter spp. were not detected in cheese samples. E. coli was found in 4 (30%) of samples while coagulase positive staphylococci were present in 9 (64%) of cheese samples. A high number of enterococci (from a min. 3.103 to a max. 15.107 cfu g–1) and coliforms (from a min. 10 to a max. 19.105 cfu g–1) were detected as well. After one month of keeping vacuum-packed ripened cheeses at 6 °C, the number of micro-organisms did not rise significantly, except for the number of yeasts and moulds which grew to 3.6·104 cfu g–1 of cheese. Because of improper milking and processing hygiene conditions, three (21%) of the tested cheese samples did not correspond to the microbiological criteria according to the applicable regulations.https://journals.uni-lj.si/aas/article/view/15424cheese-makingcritical control pointsmicrobiological qualityslovenia
spellingShingle Karmen GODIČ TORKAR
Slavica GOLC TEGER
The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makers
Acta Agriculturae Slovenica
cheese-making
critical control points
microbiological quality
slovenia
title The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makers
title_full The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makers
title_fullStr The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makers
title_full_unstemmed The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makers
title_short The microbiological quality of some critical control points in the cheese production of individual Slovenian cheese-makers
title_sort microbiological quality of some critical control points in the cheese production of individual slovenian cheese makers
topic cheese-making
critical control points
microbiological quality
slovenia
url https://journals.uni-lj.si/aas/article/view/15424
work_keys_str_mv AT karmengodictorkar themicrobiologicalqualityofsomecriticalcontrolpointsinthecheeseproductionofindividualsloveniancheesemakers
AT slavicagolcteger themicrobiologicalqualityofsomecriticalcontrolpointsinthecheeseproductionofindividualsloveniancheesemakers
AT karmengodictorkar microbiologicalqualityofsomecriticalcontrolpointsinthecheeseproductionofindividualsloveniancheesemakers
AT slavicagolcteger microbiologicalqualityofsomecriticalcontrolpointsinthecheeseproductionofindividualsloveniancheesemakers