Investigation on the Microbiological and Biochemical Properties of Kimchi in the Solid-state Model System Designed for Fermented Sausages

The objective of this study was to investigate the potential of the application of kimchi LAB as starter culture in the production of fermented sausages. For this, the solid-state model media composed to simulate the substantial conditions of meat mixtures were fermented for 120 h after the treatment with different concentrations of kimchi (0.5, 1.0, 1.5, 3.0, and 5.0%) and lyophilized kimchi-powder (0.2 % and 0.5%). During the fermentation period, the growth of total viable cells and LAB, and the changes of pH and titratable acidity were investigated. The initial LAB counts ranged from 7.18 to 8.34 Log CFU/mL for kimchi media and from 6.93 to 6.94 Log CFU/mL for kimchi-powder media depending on the added concentrations. The kimchi LAB in this study were not influenced by the immobilized condition for their adaptation and growth by showing no lag phase and thus acted similar as in the submerged medium. The initially increased counts reached around 9 Log CFU/mL in 12 h independent of the concentrations of added kimchi. However, the growth and metabolic activity of kimchi-powder LAB were influenced by the immobilized condition. Supposedly, as the nutrient supply in solid-state depended solely on diffusion, these differences in the souring properties were caused by the LAB topography in the medium matrix. Nevertheless, the differences in the numbers of LAB between two media were less than 0.5 Log units and the pH drop in the solid-state batches was quite rapid and reached low values. Therefore, it can be assumed that kimchi and kimchi-powder LAB showed the utility as the substitute of commercial starter culture even without a rehydrating pretreatment.