Fig. 1.

Application of S. carnosus in food technology. a S. carnosus is used as starter culture for sausage fermentation where dissimilatory nitrate/nitrite reduction plays an important role. b Steps in dissimilatory nitrate/nitrite reduction in S. carnosus under anaerobic conditions. (1) Nitrate is taken up by the nitrate transporter (NarT). (2) It is reduced to nitrite by nitrate reductase. (3) Nitrite is excreted and accumulates in the supernatant until nitrate is almost completely consumed. (4) Nitrite is taken up again and is ((5)) intracellularly reduced to ammonia by the NADH-dependent nitrite reductase. (6) Ammonia is excreted leading to mild alkalization of the environment