Survival of Salmonellae in orange juice

Salmonella serovars gaminara, hartford, rubislaw and typhimurium were inoculated into pasteurized orange juice adjusted to pH 3.5, 3.8, 4.1 and 4.4 and incubated at 0 and 4C. Inoculated salmonellae (10(6) colony-forming units/mL) survived in detectable numbers up to 27 days at pH 3.5, 46 days at pH 3.8, 60 days atpH 4.1, and 73 days at pH 4.4. Lag times before initial cell populations began to decline were directly correlated with pH and ranged from <1 day at pH 3.5 up to 27 days at pH 4.4. Death rates were inversely correlated with pH. Results suggest that salmonellae which might contaminate orange juice could survive sufficient time to cause illness.