Effect of proteolytic starter culture isolated from Chinese Dong fermented pork (Nanx Wudl) on microbiological, biochemical and organoleptic attributes in dry fermented sausages

The effect of a proteolytic starter culture isolated from Nanx Wudl, on microbiological, biochemical and organoleptic attributes of dry fermented sausages was investigated during processing. Based on preliminary screening, the combination of Staphylococcus xylosus SX16 and Lactobacillus plantarum CMRC6, showing excellent proteolytic activity in vitro, was selected as the multi-strain starter (starter LS). For comparison, the single-strain starter culture of L. plantarum CMRC6 (starter LB) and non-inoculated control were also tested. During fermentation, lactic acid bacteria and staphylococci dominated the microbiota and suppressed the Enterobacteriaceae growth in LS-inoculated sausages. The addition of LS starter accelerated acidification and proteolysis during ripening, improving the contents of total free amino acids and several essential free amino acids (Phe, Ile and Leu). Volatile compounds analysis revealed that LS-fermented sausage showed the highest abundance of 3-methyl-1-butanol, probably due to the inoculated S. xylosus. The inoculation of LS starter improved the sensory properties of sausages, especially the flavor attribute. Therefore, S. xylosus SX16 and L. plantarum CMRC6 are promising candidates for inclusion as multi-strain starters in the manufacture of gourmet fermented dry sausage.