Production of fermented pork jerky using Lactobacillus bulgaricus

• Lactobacillus bulgaricus could effectively ferment raw pork to pork jerky.
• The pH of fermented jerky was significantly lower than that of non-fermented jerky.
• The produced free amino acid and neutral proteases increase after fermentation.
• The protein in the pork jerky decreased after fermentation.
• Some important compounds that can affect meat flavor produced during fermentation.

Lactobacillus bulgaricus was used to produce fermented pork jerky, and a series of indexes were measured including pH, free amino acids contents, protease activities and viable count of Lacrobacillus bulgaricus of the fermented pork jerky, the non-fermented jerky, the remaining fermented medium, and the medium before fermentation. The true protein contents and volatile compounds of the jerkies before and after fermentation were also determined. The study results demonstrated that Lactobacillus bulgaricus reduced the meat pH (from 6.42 to 4.77), degraded the protein in the meat by the proteases (including acid and neutral proteases) produced during fermentation, and increased the amount of free amino acids. And the viable count of Lacrobacillus bulgaricus in the pork jerkies after fermentation was increased. Four and twenty-two volatile compounds were detected for the non-fermented and fermented jerky, respectively. The important compounds affecting the flavor of fermented jerky included 1-octen-3-ol, benzaldehyde, pentanal, octanal, nonanal, and 2-pentyl-furan. The study results demonstrated that Lactobacillus bulgaricus reduced the meat pH, degraded the protein in the meat by the proteases (including acid and neutral proteases) produced during fermentation, and increased the amount of free amino acids and flavored compounds. In these ways, the meat quality and flavor were improved, and digestion and absorption were enhanced.