Biogenic amine inhibition and quality protection of Harbin dry sausages by inoculation with Staphylococcus xylosus and Lactobacillus plantarum

• Biogenic amines were reduced in Harbin dry sausages by S. xylosus and L. plantarum.
• The growth of enterobacteriaceae was inhibited in the inoculated sausages.
• Inoculation with bacteria delayed lipid oxidation and improved the sensory quality.
• The biogenic amine concentrations correlated well with enterobacteriaceae counts.

This study was conducted to evaluate the effects of inoculation with Staphylococcus xylosus, Lactobacillus plantarum, or a mixture of strains (L. plantarum + S. xylosus) on the formation of biogenic amines (BAs) and quality characteristics in Harbin dry sausage. Microbial analysis shows that total aerobic bacteria and lactic acid bacteria (LAB) counts were higher in the inoculated sausages, especially in those inoculated with a mixture of strains, but the growth of enterobacteriaceae was inhibited (P < 0.05). A sharp decrease in the pH value of the sausages was observed, and the moisture content and water activity were significantly decreased during fermentation. Sausages inoculated with a mixture of bacterial strains had the lowest pH, moisture content and water activity (P < 0.05). Inoculation of dry sausages with S. xylosus or L. plantarum, especially a mixture of strains (L. plantarum + S. xylosus), significantly delayed lipid oxidation, improved sensory characteristics, and inhibited BA accumulation. Six types of BAs (cadaverine, putrescine, tryptamine, 2-phenylethylamine, histamine, and tyramine) were inhibited by the presence of L. plantarum and S. xylosus, and a mixture of them had the most inhibitive effect. Correlation analysis showed that the BA concentrations correlated well with enterobacteriaceae counts, and some BAs were negatively correlated with LAB counts. These results demonstrate that S. xylosus and L. plantarum could be used as starter cultures in Harbin dry sausage production to inhibit BA accumulation and improve quality characteristics.