Analysis of Cultivable Microbial Community during Kimchi Fermentation Using MALDI-TOF MS.

Eiseul Kim,Seung-Min Yang,Hae-Yeong Kim

doi:10.3390/foods10051068

Abstract

Kimchi, a traditional Korean fermented vegetable, has received considerable attention for its health-promoting effects. This study analyzes the cultivable microbial community in kimchi fermented at different temperatures using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to comprehensively understand the factors affecting the quality of kimchi. Of the 5204 strains isolated from kimchi, aligned with the in-house database, 4467 (85.8%) were correctly identified at the species level. The fermentation temperature affected the microbial community by varying the pH and acidity, which was mainly caused by temperature-dependent competition between the different lactic acid bacteria (LAB) species in kimchi. LAB, such as Levilactobacillus (Lb.) brevis and Lactiplantibacillus (Lpb.) plantarum associated with rancidity and tissue softening, proliferated faster at higher temperatures than at low temperature. In addition, LAB, such as Latilactobacillus (Lat.) sakei and Leuconostoc (Leu.) mesenteroides, which produce beneficial substances and flavor, were mainly distributed in kimchi fermented at 4 °C. This study shows as a novelty that MALDI-TOF MS is a robust and economically affordable method for investigating viable microbial communities in kimchi.

Highlights

Kimchi is known to have health-promoting effects, such as anti-oxidative and antiaging effects [1,2,3,4]
The viable cell count, pH, and acidity were monitored every sampling time changes in pH and acidity during kimchi fermentation are shown in Figure 2 decrease in pHand and increase in acidity changed more slowly at a low temperature (
MALDI-TOF MS was successfully applied to monitor the microbial community in kimchi fermented at different temperatures

Summary

Introduction

Kimchi is known to have health-promoting effects, such as anti-oxidative and antiaging effects [1,2,3,4]. It is fermented in the unsterilized natural environment, leading to the growth of various microorganisms. The fermentation of kimchi is affected by environmental factors, such as fermented temperature and ingredients. The temperature influences the quality, flavor, and shelf-life of kimchi by affecting the growth of each LAB group [9]. It is important to set an accurate temperature to improve the quality, flavor, and taste of kimchi and provide vital information concerning the environmental factors and kimchi ecosystem during fermentation

Objectives

Methods

Results

Conclusion