Use of Encapsulated and Raw Organic Acids for Inhibition of Salmonella in a Refrigerated Raw Meat-Based Diet (RMBD) Matrix for Dogs

Abstract

The rising demand for using raw meat diets (RMBDs) for feeding companion animals requires improvement in their food safety. Organic acids could be a promising anti-microbial ingredient for mitigating pathogen contamination. This study investigated the effects of encapsulated (E) and raw (R) acids (citric—CE and CR; lactic—LE and LR) on Salmonella survival in RMBDs during refrigerated storage. The acidulants (1.0% LE, 1.0% CE, 0.5% LE + 0.5% CE, 0.5% CE + 0.5% LR, 0.5% LE + 0.5% CR, and 0.5% LR + 0.5% CR) were incorporated in RMBD patties inoculated with Salmonella (ATCC 8326, ATCC 14802, and ATCC 13076) at 6 and 9 log CFU/patty levels. Inoculated (PC) and non-inoculated (NC) patties made without acidulants were used as controls. Patties were stored at 4 °C and Salmonella enumeration was done at days 0, 1, 4, 7, 10, 13, 16, 19, and 22. Salmonella reduction was higher (p < 0.05) in stored patties with both encapsulated and raw acids (3.10–4.10 logs) added relative to using individual encapsulated acids (2.40–3.70 logs) and control (0.70–0.90 logs). Higher inoculation levels resulted in greater (p < 0.05) Salmonella reductions in the patties after storage. The reductions were influenced (p < 0.05) by the treatment × time interaction with longer storage time resulting in higher reductions. The Salmonella inactivation under all acid treatments followed the Weibull model (R2—0.86 to 0.98; RMSE—0.19 to 0.34; β—1.23 to 2.08). The results show that encapsulated organic acids can inhibit Salmonella growth and survival in RMBDs under refrigerated conditions. The results from this study could be used as basis for improving the food safety of RMBDs.