Isolation of Listeria monocytogenes from milks used for Iranian traditional cheese in Lighvan cheese factories
Mir-Hassan Moosavy 1, Saber Esmaeili 2, Ehsan Mostafavi 2, Fahimeh Bagheri Amiri 3 1 - Department of Food Hygiene and Aquatic, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran 2 - Department of Epidemiology, Pasteur Institute of Iran, Tehran, Iran 3 - Department of Epidemiology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Ann Agric Environ Med 2014; 21 (4): ICID: 1129923 Article type: Original article
Traditional Lighvan cheese is a semi-hard cheese which has a popular market in Iran and neighboring countries. The aim of this study was evaluating the contamination of milks used for Lighvan cheese making with Listeria monocytogenes. Raw milk samples were randomly collected from different cheese producing factories (sampling carried out from large milk tanks used cheese making in factories). Isolation of L. monocytogenes was performed according to ISO 11290 and biochemical tests were done to identify and confirm L. monocytogenes. 9 samples (50%) of the 18 collected samples from milk tanks in Lighvan cheese producing factories were contaminated with L. monocytogenes. The concentration of L. monocytogenes in all 9 positive samples was 40 CFU/ml. This study is the first report of L. monocytogenes contamination in raw milks used for Lighvan cheese production in Iran. Regarding the fact that these cheeses are produced from raw milk and no heating process is performed on them its milk contamination can be a potential risk for consumers.
DOI: 10.5604/12321966.1129923 PMID 25528910 - click here to show this article in PubMed