Retention of Viability of Salmonella in Sucrose as Affected by Type of Inoculum, Water Activity, and Storage Temperature

ABSTRACT Outbreaks of salmonellosis have been associated with consumption of high-sugar, low–water activity (aw) foods. The study reported here was focused on determining the effect of storage temperature (5 and 25°C) on survival of initially high and low levels of Salmonella in dry-inoculated sucrose (aw 0.26 ± 0.01 to 0.54 ± 0.01) and wet-inoculated sucrose (aw 0.24 ± 0.01 to 0.44 ± 0.04) over a 52-week period. With the exception of dry-inoculated sucrose at aw 0.26, Salmonella survived for 52 weeks in dry- and wet-inoculated sucrose stored at 5 and 25°C. Retention of viability was clearly favored in sucrose stored at 5°C compared with 25°C, regardless of level or type of inoculum or aw. Survival at 5°C was not affected by aw. Initial high-inoculum counts of 5.18 and 5.25 log CFU/g of dry-inoculated sucrose (aw 0.26 and 0.54, respectively) stored for 52 weeks at 5°C decreased by 0.56 and 0.53 log CFU/g; counts decreased by >4.18 and >4.25 log CFU/g in samples stored at 25°C. Inactivation rates in wet-in...