Fate of Pathogens During Fermentation, Drying, and Storage of Salami Cured with Various Sources of Nitrite

As interest in “clean label” foods increases, concerns regarding pathogen inhibition in naturally cured meats have been raised due to nitrite’s antimicrobial efficacy. Although research exists that addresses the safety of naturally cured meat, limited work investigates this concern in fermented and dried products manufactured with nitrite alternatives. Therefore, research was conducted to determine the survival of Escherichia coli O157:H7 (EC), Listeria monocytogenes (LM), and Salmonella spp. (S) in raw, ready-to-eat salami manufactured with various nitrite alternatives. Three independent replications of 4 treatments were evaluated: negative control, positive control (PC; purified/conventional sodium nitrite), Swiss chard powder (SC), and Prosur T-10 (T-10), a commercial dried fruit extract. PC and SC were formulated to 156 ppm. T-10 was formulated to 0.96% of the total formulation. All treatments were formulated using manufacturers’ guidelines for appropriate ingredient utilization. To prepare the salami, pork shoulder butts were ground and inoculated with a 3-strain culture of EC, LM, and S to obtain approximately 7 log10 CFU/g. Dry ingredients and starter culture then were mixed and stuffed into fibrous casings of about 55 mm, fermented (pH < 5.0), and dried to a target water activity (aw) of 0.88 in a commercial drying cabinet. After drying, salamis were vacuum packaged and stored (20 ± 0.003°C). Salamis were sampled for pathogen survival, pH, and aw at raw manufacturing, throughout the 3-d fermentation, every week for 7 wk, and on day 118 (n =9; N = 432). Greater than 2 log10 CFU/g reduction of LM and S was achieved by PC and SC. Processors may use this research as scientific support if they manufacture pork salami with 156 ppm nitrite sourced from purified nitrite or SC, ferment to a pH of less than 5.0, have a final aw of less than 0.88, and have an ingoing salt content of 2.5%.