The presence of some pathogen micro organisms, yeasts and moulds in cheese samples produced at small dairy-processing plants

Godič Torkar, Karmen (avtor), Golc-Teger, Slavica (avtor)

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 atfive small dairy-processing plants. The mean number of coagulase-positive staphylococci in all tested samples was 2.5 * 104 cfu[1] g-1, while the numberof 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. grazi 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.

• Jezik: Angleški jezik
• Ključne besede: milk products, cheese, microbiology, pathogen micro-organisms, yeasts, moulds, aflatoxins
• Vrsta gradiva: Delo ni kategorizirano
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: BF - Biotehniška fakulteta
• Založnik: Biotehniška fakulteta
• Leto izida: 2006
• Št. strani: Str. 37-51
• Številčenje: Letn. 88, št. 1
• PID: 20.500.12556/RUL-59924
• UDK: 637.1:579
• ISSN pri članku: 1581-9175
• COBISS.SI-ID: 1968776
• Datum objave v RUL: 10.07.2015

GODIČ TORKAR, Karmen in GOLC-TEGER, Slavica, 2006, The presence of some pathogen micro organisms, yeasts and moulds in cheese samples produced at small dairy-processing plants. Acta agriculturae Slovenica [na spletu]. 2006. Vol. 88, no. 1, p. 37–51. [Dostopano 14 april 2025]. Pridobljeno s: http://www.dlib.si/details/URN:NBN:SI:doc-ZWZII4B1

Gradivo je del revije

• Naslov: Acta agriculturae Slovenica
• Skrajšan naslov: Acta agric. Slov.
• Založnik: Biotehniška fakulteta
• ISSN: 1581-9175
• COBISS.SI-ID: 213840640

Sekundarni jezik

• Jezik: Slovenski jezik
• Naslov: Prisotnost nekaterih patogenih mikroorganizmov, kvasovk in plesni v vzorcih sira, proizvedenih v malih mlekarsko-predelovalnih obratih

Izvleček

Proučevali smo prisotnost patogenih in nekaterih indikatorskih mikroorganizmov v 40 vzorcih sira, od tega v 14 vzorcih skute, 13 vzorcih soljenega ali nesoljenega svežega (mehkega) sira in 13 vzorcih poltrdega tipa sira, proizvedenih v petih malih mlekarsko-predelovalnih obratih. Povprečno število koagulaza-pozitivnih stafilokokov v vseh vzorcih je znašalo 2,5 * 104 KE[1] g-1, medtem ko je bilo število bakterij vrste E. coli 1,4 * 106 KE g-1. Izmed 40 vzorcev je v 20.0 % število koagulaza- pozitivnih stafilokokov presegalo slovenske veljavne normative, posebno v vzorcih mehkega sira (12,5 %) in skute (7,5 %). Okrog 17,5 % vzorcev je bilo okuženo z bakterijami E. coliv višjih koncentracijah, kot to dovoljujejo slovenski veljavni predpisi. Število bakterij E. coli je bilo previsoko v vzorcih mehkega sira (12,5 %) in skute (5,0 %). En vzorec poltrdega sira je vseboval sulfid-reducirajoče klostridije. Vrste rodu Proteus smo ugotovili v 3 (7,5 %) in L. grayi v 1 (2,5%) vzorcev. Salmonella in L. monocytogenes nista bili ugotovljeni v nobenem izmed preiskanih vzorcev. Izmed 40 preiskanih vzorcev jih 9 (22,5 %) ni ustrezalo veljavnim slovenskim normativom glede njihove mikrobiološke kakovosti. Tako kvasovke kot plesni so bile izolirane iz 60 % preiskanih vzorcev. Povprečno število kvasovk je bilo 5,8 * 104 KE g-1 in plesni 2,0 * 104 KE g-1 vzorca. Najpogosteje so bile izolirane plesni iz rodov Geotrichum (91,9 %), Moniliella (5,4 %) in Aspergillus (2,7 %). Sev iy rodu Aspergillus ni pripadal vrstama A. flavus /parasiticus in tudi ni tvoril aflatoksinov.

• Ključne besede: mlečni izdelki, siri, mikrobiologija, patogeni mikroorganizmi, kvasovke, plesni, aflatoksini