Equivalent Pasteurization Temperatures to Kill Salmonellae in Liquid Egg White at Various pH Levels

Abstract

THE pH of the medium has a major influence on the susceptibility of bacteria to heat. Hansen and Riemann (1963), in a review of factors affecting the heat resistance of nonsporing organisms, indicated that maximum resistance usually occurs near neutrality. Most pasteurization studies either have not considered or have given little attention to pH as a variable in altering the time and/or temperature required to kill bacteria in liquid egg white (EW).A review of the literature revealed the following information on the pH of EW during pasteurization. Ayres and Slosberg (1949) readjusted the pH of fermented EW to 9.0 before flash pasteurization at 59.4°C. A patent by van Olphen (1953) claimed that pathogenic bacteria in EW could be destroyed by increasing the pH to 9–12, then pasteurizing at 40–55°C. Elleman (1955) referred to a similar process which called for adjusting the pH of EW to 10.5 with NH4OH, holding .