In relation to LAB counts, our resu

In relation to LAB counts, our results are in accordance with previous studies that have shown that these bacteria are quite insensitive to nitrite. Korkeala, Alanko, and Tiusanen (1992) observed in in vitro studies in MRS broth added with different nitrite concentrations, thatLAB seemed to grow well at levels up to 100 mg/l, while a clear reduction was found at 400 mg/l. Furthermore, heterofermentative LAB are more sensitive than homofermentative ones (Dodds & Collins-Thompson, 1984; Korkeala et al., 1992). LAB lack the ironsulfur enzyme ferredoxin, which is inhibited by nitrite, and is involved in ATP synthesis from pyruvate in other microorganisms such as C. botulinum (Jay, 2000).