Survivability of Salmonella and Enterococcus faecium in chili, cinnamon and black pepper powders during storage and isothermal treatments

Abstract

Outbreaks and recalls associated with foods containing spices suggest a need for risk assessment of Salmonella in spices. In this study, the survivability of Salmonella Enteritidis PT 30, Salmonella cocktail (S. Enteritidis PT 30, S. Tennessee K4643 and S. Agona 447967), and Enterococcus faecium NRRL B-2354 in chili, cinnamon and black pepper at water activities (aw) 0.3 and 0.5 were evaluated during one-year storage at 21 °C. The thermal resistance of Salmonella cocktail in spices was also evaluated at 70 °C before and after storage. At aw 0.5, 4-month storage caused 5 log reduction of Salmonella cocktail in chili, while 8 months led to the same level of reduction in cinnamon. But only 3 log reduction were observed in black pepper over one year. Storage at aw 0.3 caused less reduction in Salmonella cocktail during the same storage periods. Less than 2 log reduction of E. faecium were observed over the one year storage at both aw levels, except for in chili stored at 0.5 aw. The D70°C-values for Salmonella cocktail in chili, cinnamon and black pepper of aw 0.3 before storage were 15.4, 20.8 and 36.6 min, respectively. 21–50% drops in the D70°C-value were obtained after two-month of storage, mostly in chili and least in black pepper. The high D70°C-value in black pepper persisted over one-year storage. Based on these results, chili powder showed the highest antimicrobial effect, followed by cinnamon and black pepper powders during storage and isothermal treatments.