The objective of this study was to investigate the potential of the application of lactic acid bacteria (LAB) from kimchi as a starter culture in the production of fermented sausages. To achieve this, a submerged model medium that contained LAB as part of a complex system of kimchi (0.5, 1.0, 1.0, 3.0, and 5.0%) and lyophilized kimchi powder (0.2 and 0.5%) was fermented for 120 h. During the fermentation period, the growth of total viable organisms and LAB, and the changes in the pH and the titratable acidity, were investigated. The initial LAB counts ranged from 6.4 to 7.7 Log CFU/mL for the kimchi media, and from 6.9 to 6.9 Log CFU/mL for the kimchi powder media. In all the kimchi batches, the LAB increased logarithmically, and the highest LAB counts (around 9 Log CFU/mL) were reached in 24 h. An evident lag phase of the LAB was observed in the kimchi powder samples and reached 8.8 Log CFU/mL in 8 h. The decrease in the pH and the formation of lactic acid were rapid in the kimchi batches, and reached pH values of 3.4-3.5 in 12 h. With these results, the LAB that was integrated with the addition of kimchi or kimchi powder demonstrated its potential utility as a substitute for starter culture.

The microbial distribution of raw materials and beef jerky, and the effect of nisin on the growth of Bacillus cereus inoculated in beef jerky during storage, were studied. Five strains of pathogenic B. cereus were detected in beef jerky, and identified with 99.8% agreement using API CHB 50 kit. To evaluate the effect of nisin, beef jerky was inoculated with approximately 3 Log CFU/g of B. cereus mixed culture and nisin (100 IU/g and 500 IU/g). During the storage of beef jerky without nisin, the number of mesophilic bacteria and B. cereus increased unlikely for beef jerky with nisin. B. cereus started to grow after 3 d in 100 IU nisin/g treatment, and after 21 d in 500 IU nisin/g treatment. The results suggest that nisin could be an effective approach to extend the shelf-life, and improve the microbial safety of beef jerky, during storage.