The role of bacterial fermentation in lipolysis and lipid oxidation in Harbin dry sausages and its flavour development

- Bacterial fermentation promoted lipid hydrolysis and inhibited lipid autoxidation.
- The predominant free fatty acids were palmitic acid, stearic acid and oleic acid.
- Bacterial fermentation decreased PV and TBARS in Harbin dry sausages.
- Fermentation with multiple strains reduced undesirable flavour development.

Pediococcus pentosaceus, Lactobacillus curvatus, Lactobacillus sakei and Staphylococcus xylosus were evaluated to determine their roles in the lipolysis and lipid oxidation in Harbin dry sausages and their relation to flavour development. The free fatty acid (FFA) contents of both muscle and fat tissues were higher in the inoculated sausages than those of the non-inoculated control, especially with mixed strains (P < 0.05). The predominant FFAs in both tissues at the end of the fermentation were palmitic acid, stearic acid and oleic acid. The inoculation of dry sausages with bacterial strains, especially mixed strains, significantly decreased the peroxide value and thiobarbituric acid reactive substances (P < 0.05). Furthermore, a lower level of volatile compounds related to lipid-oxidation, such as aldehydes, ketones and hydrocarbons, was observed in the inoculated sausage (P < 0.05). The results demonstrate that Harbin dry sausage can be inoculated with a starter culture mixture of P. pentosaceus, L. curvatus and S. xylosus to promote lipid hydrolysis, inhibit lipid autoxidation and improve fermented flavour development.