Microbial safety criteria and quality of traditional Egyptian Karish cheese

Abstract

Some traditional fermented dairy products like Egyptian Karish cheese and traditional fermented milk (Laban Zeer) are manufactured in farmhouses following traditional techniques using raw milk without heat treatment or addition of selected starter cultures, these products are generally designed as "artisanal". The representative Karish samples were analyzed for their content of total microbial, Enterobacteriaceae, yeast, molds, Staphylococci coagulase positive, Salmonella spp., Listeria spp., in addition to detection of Bacillus cereus, Listeria monocytogenes, Clostridium perfringens and Campylobacter spp. using classical methods. The physico-chemical properties of collected samples showed that the average of protein, fat, moisture and acidity were in accepted range with that reported in literatures and Egyptian standard. Some lactic acid bacteria (Lactococcus lactis supsp. lactis, Lactobacillus delbrueckii subsp. lactis and Enterococcus feacium) were isolated and identified from fresh karish cheese using classical methods followed by rep-PCR. Lactococcus garvieae was detected in fresh samples using TTGE but could not be detected using classical methods. The results of microbiological analysis showed the presence of high numbers of Enterobacteriaceae that ranged from log 10 2.6 cfu/g to log 10 3.5 cfu/g, Bacillus ssp. ranged from log 10 4.2 cfu/g to log 10 5.6 cfu/g, Staphylococci counts are ranged from log 10 1.8 cfu/g to log 10 2.7 cfu/g, faecal enterococci count ranged from log10 3.5 cfu/g to log10 5.8 cfu/g. Yeasts and molds count ranged from log 10 2.7 cfu/g to log 10 3.5 cfu/g. B. cereus, L. monocytogenes, C. perfringens, Shigella, Salmonella, Escherichia coli β-glucuronidase positive and Campylobacter spp. were not detected in all the examined samples. The count of undesirable microorganisms indicated the poor hygienic practice of traditional Karish cheese production; starting with using poor quality of raw milk and processing under uncontrolled environments. This would require using clean raw milk, controlled manufacturing steps and selection of the appropriate starter culture for the fermentation.

Identification of S.aureus and E.coli from Dairy Products Intended for Human Consumption

“…The highest frequency distribu-tion of S. aureus in kariesh cheese was 92% whichlies within the range of 10 4 ≤ 10 7 . Contamination can occur from different source include the poor quality of raw milk and processing in uncontrolled environments (Sameh, 2016). The highest frequency distribution of S. aureus in raw milk was 80% whichlies within the range of 10 4 ≤ 10 6 .…”

“…November 2018 | Volume 6 | Issue 11 | Page 511 (Ombarak et al, 2016) as this type of cheese is homemade and sold from door to door or sold in local markets (FAO, 1999). Different sources might be implicated in microbial contamination of kariesh cheese as starting with using poor quality of raw milk, processing under uncontrolled environments and selection of the inappropriate starter culture for the fermentation (Awad, 2016). Raw Milk serves as an excellent medium for the growth of many microorganisms and the highest frequency distribution of E. coli in raw milk was 60% lies within the range of 10 4 ≤ 10 6 .…”

Utilization of Cyanobacteria Extracts in Improving the Microbial Quality of Soft White Cheese

“…In the present study, 88% of samples were satisfactory for S. aureus in Talaga cheese which lies within the range of 10 5 ≤ 10 7 . Contamination can occur from different source include the poor quality of raw milk and processing in uncontrolled environments (Sameh, 2016). The presence of S. aureus in cheese usually indicates contamination of milk from diseased udder or external surface of the dairy animals, or from contaminated, unclean hands of the dairy workers or from their sneezing and coughing (Salem et al, 2016).…”

Quality evaluation of Braided Cheese (Gibna mudaffara) made from raw milk with the addition of starter culture during the ripening period

“…The starter culture addition increased the contents of protein, total solids, ash contents and titratable acidity, and did not affect the contents of moisture and fat. The chemical composition and physical properties of cheese are influenced by many factors, such as the type of milk, the season of milk production, the fat separation method used, the microflora of the milk and/or the addition of starter cultures, the additives in the milk and the storage time and temperature [23]. Increasing the rate of starter culture in heat-treated buffalo milk Feta type cheese was found to increase fat, protein, moisture content, and decrease total solids content [24].…”