Effects of pulsed electric fields (PEFs) on fermentation quality characteristics and microbial community of kimchi

Abstract

Kimchi, a lactic acid bacteria (LAB)-fermented food, is consumed globally at approximately 1.5 million tons annually. This study evaluated, for the first time, the effect of pulsed electric field (PEF) pretreatment on the microbial community of kimchi. Chinese cabbage was pretreated at 1.5 kV/cm, brined with varying NaCl concentrations (5, 10, or 15 g/L), and fermented at 4 °C for 25 days. PEF pretreatment effectively maintained cellular integrity and volume. The dominant microbial taxa differed based on pretreatment, with Weissella prevailing in PEF-treated groups and Lactobacillus in untreated samples. PEF pretreatment inhibited Lactobacillus growth, the primary lactic acid producer, resulting in distinct sensory profiles compared with untreated samples. The PEF-treated group exhibited a slower LAB growth rate, with fermentation delayed by approximately 5–7 days, compared with the untreated group. These findings suggest that PEF pretreatment can effectively control the fermentation and microbial composition of kimchi, extending the shelf life.