Effect of salt concentration on quality of Chinese northeast sauerkraut fermented by Leuconostoc mesenteroides and Lactobacillus plantarum

Sauerkraut is one of the most popular traditional fermented foods in northeastern China. The traditional northeast sauerkraut is mainly based on natural fermentation at a certain salt concentration. Salt concentration has important effects on the microbial structure, the dynamic changes of metabolites and sensory quality of sauerkraut. To study the effects of different salt concentrations on the fermentation of northeast sauerkraut, Leuconostoc mesenteroides ORC 2 and Lactobacillus plantarum HBUAS 51041 were used as starter strains and fermented at four salt concentrations (0.5, 1.5, 2.5, 3.5%), respectively. Changes of pH, titratable acid (TA), nitrite, amino acid nitrogen (AAN), reducing sugar, microbial counts (lactic acid bacteria, yeasts, total coliforms), metabolites (organic acids, alcohols and sugars) and sensory were studied, which showed that 0.5% salt concentration had positive effects on the microbial metabolism and sensory quality of sauerkraut. Compared with other three salt concentrations, the glucose and fructose of 0.5% group were metabolized more fully to accumulate significantly (p < 0.05) more organic acids. In conclusion, 0.5% salt significantly accelerated the maturation and improved the sensory quality of sauerkraut. The sensory quality of northeast sauerkraut fermented at 0.5% salt concentration was the best.