Coliforms Contamination in Raw Milk and Some Dairy Products with Special Reference to Comparative Identification of Enterobacter spp.

Abstract

The current study was undertaken to examine 200 sample of raw milk and some dairy products (Kariesh cheese, plain yoghurt, milk powder and infant formula) for contamination with Coliform group especially Enterobacter spp. Coliforms were detected in; 42/50 (84%) raw milk samples from farmers' houses, 25/30 (83.33%) kariesh cheese samples and 23/30 (76.67%) plain yoghurt samples, however, they could not be detected in any of raw milk samples from dairy shops, milk powder and infant formula samples. The mean values of coliforms in the examined samples were 2.80x10 6 ±0.73x10 5 , 2.30×10 6 ±0.75×10 4 and 1.08×10 6 ± 1.50×10 4 cfu /ml or gm in raw milk from farmers' houses, kariesh cheese and plain yoghurt samples, respectively. The biochemically identified coliforms were E.

Influence of lysozyme utilization with lactic acid bacteria in yoghurt on some foodborne pathogens

“…These samples were failed to comply with EOSQC (2005) as yoghurt must be free from E. coli. The contamination rate of E. coli in our examined samples was less than those reported by Fathi et al(2019), Younis et al(2020),and Hassan et al(2021 who detect it in 36.96%, 80%, and 25%, respectively, in their examined yoghurt samples collected from different localities in Egypt, while Sayed (2012) couldn't isolate E. coli. The different prevalence rates between studies may indicate poor hygienic conditions during yoghurt manufacturing and handling, as its presence in yoghurt referred to post pasteurization contami- nation either before or during the packaging process (Omola et al, 2014).…”

“…Coliforms are a group of Gram-negative bacteria of public health concern that frequently contaminate dairy products through several sources causing food illnesses (Giammanco et al, 2011).According to EOSQC (2005), coliforms count in yoghurt should be less than 10 CFU/g, in this study 86% of yoghurt samples were failed to comply with this permissible limit.Previous Egyptian studies detected coliforms at different rates as 50%, 76.67% of yoghurt samples examined by El-Leboudy et al( 2017), Fathi et al(2019),respectively. High levels of coliforms in yoghurt may not only indicate fecal contamination but also give an indication of using low-quality raw milk, improper heat treatment, unhygienic manufacturing practices or contamination after processing,poor personnel hygiene,and using of unclean equipment and/ or contaminated water (El-Kholyet al,2014).…”