Bacteriological Control of Food Equipment Surfaces by Cleaning Systems. III. Complementary Cleaning

Abstract

Complementary use of alkaline and acidic detergents within one system for soak cleaning was examined. A cleaning simulator was used to determine the changes in soil and bacterial numbers on stainless steel and rubber surfaces over 28 soiling and washing cycles (each of 12 h) with four cleaning systems. The soiling milk was inoculated with 5 x lQS Streptococcus faecalis and 5 x 10 5 Escherichia coli colony forming units/mi. In one system the soiling milk was followed by a wash with a chlorinated · alkaline detergent (20 C) and two rinses of cold water (20 C) and an intercycle period of 9.5 h.