Heterogeneity of Spoilage Potential of Meat-borne Bacillus

In order to assessing the heterogeneity of Bacillus sp. isolates spoilage potential, six Bacillus sp. isolates isolated from spoiled low-temperature sausages were used to investigate the heterogeneity of their spoilage properties at 20 ℃ (room temperature) and 37 ℃ (optimum growth temperature). The growth curve, acid production capacity, gas production capacity, protease activity, lipase activity, and amylase activity of six strains of Bacillus sp. were measured in the experiment. The results revealed that Bacillus cereus (C) had the greatest capacity for producing acid and that after 48 hours at 37 ℃, the pH in the culture medium dropped by 0.71 relative to the blank control group. Following a 5-day culture at 37 ℃, Bacillus amyloliquefaciens (G) displayed the greatest protease and amylase activities, with a maximum protease activity of 7.17 U/mL and a decomposition circle area of starch agar of 16.53 cm². Bacillus cereus (C) exhibited the least comprehensive spoiling ability, as evidenced by its protease activity of 2.63 U/mL and the decomposition circle area of starch agar of 7.55 cm² after 5 days of culture at 37 ℃. Furthermore, it was discovered that the growth temperature significantly impacted the spoilage potential of the strains. In summary, there was great heterogeneity in the spoilage characteristics of Bacillus sp.. When examining its spoilage traits, it is important to consider this heterogeneity.