Microbiological Quality Evaluation of Various Types Of Traditional Romanian Cheese Through Advanced Methods

Abstract

Raw milk represents a nutritive environment for a number of pathogens, like Salmonella spp., Escherichia coli O157: H7, Staphylococcus aureus etc. This fact can cause a serious of foodborne outbreaks associated to the consumption of contaminated milk and derivated products. The traditional processing of raw milk in poor hygiene conditions can pose a serious microbiological risk. The study aimed at evaluating the incidence of pathogen bacteria in ripened traditional cheese by advanced biochemical and molecular methods in order to reveal the possible risk of consumer exposure. The study was applied on 150 samples of riepened cheese from the follwoing types: salted teleme cheese and „Burduf” cheese and „Năsal” cheese. The traditional teleme cheese presented an average value of the total E. coli count in between 11.06±0.52-38.33±2.76 cfu/g. The risk represented by the presence of E. coli and Staphylococcus aureus is low within the first steps of ripening, being absent after 28 months of ripeneing in the teleme cheese samples. The Staphylococcus aureus load was in between 3.82±0.12 log cfu/g for the first period of ripeneing in „Burduf” cheese and 0.27±0.56 log cfu/g after the second period of maturation, following a descendant pathway towards the last period of ripening. In „Năsal” cheese we isolated the specific Brevibacterium linens, which gives the characteristics of this type of cheese, but also Micrococcus spp., in 35% and lactic streptococci in 20%. The traditional cheese evaluated represent a low risk of contamination given that no sample investigated has exceeded the maximum limits allowed by the legislation and no pathogen bacteria isolated.