Investigation of quality attributes and inhibition of foodborne pathogens in 'no-nitrate or nitrite-added' bacon

Processed meats manufactured using natural curing ingredients may exhibit color, flavor and shelf-life similar to traditional products. Naturally-cured meat products are labeled "no-nitrate or nitrite-added" and research has focused on hams and cooked sausages. There is limited research on the ability of these ingredients to inhibit foodborne pathogens. The objective of the research was to investigate quality attributes and inhibition of foodborne pathogens of "no-nitrate or nitrite-added" bacon. Two natural cure ingredients were investigated: one that required the reduction of nitrate (natural nitrate) during manufacturing, and the other, was a product that has been pre-reduced (natural nitrite). Three studies were conducted. Preliminary research found that the reduction of nitrate may be inhibited by salt. Nitrate reduction for 12 hours produced 48 ppm nitrite without salt vs 1 ppm nitrite with salt. Pre-converting without salt may save time during manufacturing. A second study investigated the quality attributes of "no-nitrate or nitrite-added" bacon. Bacon cured with natural nitrate with starter culture could have similar residual nitrite levels as sodium nitrite-cured bacon (44 ppm for naturally-cured vs 38 ppm for conventionally-cured at day 35). Natural nitrate or natural nitrite-cured bacon faded in color more quickly than bacon cured with sodium nitrite (a* value 3.14 vs 5.37) (P < 0.05) than all other treatments. The final study investigated the inhibition of foodborne pathogens: Salmonella Typhimurium (ST), Escherichia coli O157:H7 (EC), Listeria monocytogenes (LM), and Clostridium perfringens (CP) in brine and bacon. The brine study we found that brines with natural nitrate, natural nitrite, and sodium nitrite all decreased pathogen growth (ST, LM, CP) in solution to a similar degree (less than log10 2 CFU/mL) (P > 0.05) within 24 hours. The bacon phase showed no differences in pathogen reduction in a bacon system at the end of the 21-day shelf-life study for all cures. However, when treatments were pooled over storage time sodium nitrite was more effective at slowing CP growth than all other treatments (log10 1.9 CFU/g for naturally-cured vs log10 0.6 CFU/g for sodium nitrite-cured). We concluded that "no-nitrate or nitrite-added" bacon is less red and inhibits CP less than conventionally-cured bacon.;Keywords: bacon, natural, nitrate, nitrite, color, foodborne pathogens.