1)Laboratory of Food, Biomedical and Environmental Microbiology (LAMAABE), Abou Bakr Belkaid University, Tlemcen, Algeria; 2)Departamento de Microbiología y Bioquímica, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain; 3)Laboratoire universitaire de biodiversité et écologie microbienne, LUBEM Université de Bretagne Occidentale, Brest, France; 4)Institute of Applied Sciences and Techniques “ISTA”, University of Tlemcen, Alegria; 5)Department of Biology, Faculty of Science, Amar Telidji University, Laghouat, Algeria
Asmaa Cherif Anntar1,4), Mohamed Salih Barka1,4), Ibrahim Benamar1,5), Nahida Bendimered1,4), Karima Boumediene1), Baltasar Mayo2), Ivan Leguirinel3), Buomedine Moussa Boudjemaa1,4)
The formation of bacterial biofilm in dairy plant is the main source of milk and related dairy products contamination which is commonly related to improper Cleaning and Disinfection (C&D). Cleaning-In-Place (CIP) is the conventional process described to clean and remove on milk residues and bacterial contaminants from dairy processing lines. In this study, effectiveness of 3, 5 and 7 steps CIP protocols was evaluated against Enterococcus faecalis (E. faecalis) mature biofilms formed on stainless steel (SS) coupons. The results revealed that the most effective treatment was the 7 step protocol based on 2% sodium hydroxide (NaOH) cleaning combined with 3% enzyme mixture at 50°C for 20 minutes followed by 1% nitric acid (HNO3) at 55°C for 20 minutes and completed by 0.5% quaternary ammonium at 25°C for 20 minutes showed a significant difference in the number of recovered cells between untreated and treated coupons with a value of 5.32 log cfu/cm2 which was a very satisfying reduction level followed by CIP 2 with 4 log reduction value and CIP 1 presented by 3.14 log reduction. Even with 5 log reduction, a complete E. faecalis biofilm removal was not reached, showing persistence of mature biofilm to C&D protocols.
Keywords: biofilm, cleaning in place, dairy industry, Enterococcus faecalis, stainless steel
Arch Lebensmittelhyg 73,
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