Recovery of Escherichia Coli O157:H7 and Salmonella in Milk and Cream of Chicken Soup from High Hydrostatic Pressure (HHP) and Bacteriocin Applications Upon Storage

Abstract

By the application of HHP; more than 8 log cycle reduction was achieved for E. coli O157:H7 933 and Salmonella FDA in milk and cream of chicken soup in 5 min. Storage of HHP treated milk samples showed absence of both bacteria for 24 h at 4 °C and for 48 h at 37 °C. The population of the strains in cream of chicken soup exceeded their initial value after 5 days of storage at 25 °C. BP 1 was combined with HHP and used for inhibition of surviving bacterial species in cream of chicken soup. There was at least 7 log cycle reduction in E. coli O157:H7 933 and Salmonella FDA after 5 and 7 days of storage at 25 °C respectively, when compared to HHP alone. Combination of HHP with BP 1 extended the shelf life of cream of chicken soup for both bacterial species an additional 2 days at 25 °C when compared with HHP treatment alone.