Biofilm Formation and Contamination of Cheese by Nonstarter Lactic Acid Bacteria in The Dairy Environment

摘要

Defects in cheese, such as undesirable flavors, gas formation, or white surface haze from calcium lactate crystals, can result from growth of nonstarter lactic acid bacteria (NSLAB). The potential for biofilm forma - tion by NSLAB during cheese manufacturing, the effect of cleaning and sanitizing on the biofilm, and bacterial growth and formation of defects during ripening of the contaminated cheese were studied. Stirred-curd Ched - dar cheese was made in the presence of stainless steel chips containing biofilms of either of two strains of erythromycin-resistant NSLAB (Lactobacillus curva - tus strain JBL2126 or Lactobacillus fermentum strain AWL4001). During ripening, the cheese was assayed For total lactic acid bacteria, numbers of NSLAB, and Percentage of lactic acid isomers.