Variations in nutritional and microbial composition of napa cabbage kimchi during refrigerated storage

Abstract

The health benefits of kimchi are proven to be effective against many diseases. We studied the effects of prolonged refrigerated storage on health beneficial qualities of napa cabbage kimchi by assessing variations in nutritional composition, microbial diversity, total antioxidant capacity (TAC), and total polyphenol content (TPC). The carbohydrate content of kimchi drastically reduced during the first month of storage (from 58.7 to 41.6 g/100 g), while fat and ash contents increased. Total bacterial count declined (>80 folds) during 17 months of storage with no development of pathogenic microbes. Microbial diversity did not significantly alter during kimchi storage. Relative abundances of Lactobacillales and Firmicutes increased up to 3 months and Actinobacteria increased after 3 months of storage. TAC and TPC of kimchi increased up to 3 months of storage and declined after. The findings suggest consuming kimchi during the first 3 months of refrigerated storage to optimize beneficial microbes and health benefits. Novelty impact statement Evaluation of variations in health beneficial qualities of napa cabbage kimchi under prolonged refrigerated storage is important to determine the optimum time for consumption. The abundance of beneficial Lactobacillales bacteria increases together with total antioxidant capacity and total polyphenol content in tested kimchi up to 3 months of storage before declining. Tested commercial kimchi can be consumed within 3 months of refrigerated storage for optimum health benefits.