Growth of Lactic Acid Bacteria and Quality Characteristics of Baechu Kimchi Prepared with Various Salts and Concentration

Abstract

This study was conducted to evaluate the growth of lactic acid bacteria and quality characteristics of Baechu kimchi prepared with four types of salt (Solar salt, Flower salt, Hanju salt, and Roasted salt) at two different concentrations (10, 15%) during storage. The quality characteristics of kimchi were examined by investigating acid production, growth of lactic acid bacteria, sensory properties, salinity, texture, and color characteristics. Baechu kimchi was fermented for 18 days at 10 o C. The pH and total acidity did not change during storage according to type and concentration of salt. Growth of lactic acid bacteria was not affected by type of salt, whereas it was inhibited at 15% salt concentration after 9 days of fermentation. In the quantitative descriptive analysis of sensory properties, kimchi prepared with 10% salt showed significantly higher scores in term of overall acceptability (p<0.05). Meanwhile, there was no significant difference by type of salt. For texture characteristics, hardness of kimchi prepared with 10% salt was significantly higher than that with 20% salt. For color characteristics, L value (brightness) and b values (yellowness) of kimchi prepared with 10% salt increased during fermentation, whereas a value (redness) did not change by type and concentration of salt. The results of this study show that there were no considerable differences in quality characteristics of Baechu kimchi prepared with various types and concentrations of salt. However, Solar salt resulted in more favorable sensory properties and salinity of kimchi than any other types. Further, kimchi prepared with 10% salt showed significantly higher scores in terms of overall acceptability, growth of lactic acid bacteria, salinity, texture, and color characteristics.

Profiling of fermentative metabolites in kimchi: Volatile and non-volatile organic acids

“…Baechu kimchi is very spicy and also provides exceptionally sour, sweet, and carbonated tastes. In addition, it is rich in diverse nutrients including vitamin C, β-carotene, vitamin B complex, calcium, iron, potassium, and dietary fibers (Kim et al, 2006). Kimchi is primarily fermented by LAB such as Leuconostoc and Lactobacillus that produce various organic acids including lactic acid, acetic acid, propionic acid, benzoic acid, and sorbic acid (Kim et al, 2006).…”

“…In addition, it is rich in diverse nutrients including vitamin C, β-carotene, vitamin B complex, calcium, iron, potassium, and dietary fibers (Kim et al, 2006). Kimchi is primarily fermented by LAB such as Leuconostoc and Lactobacillus that produce various organic acids including lactic acid, acetic acid, propionic acid, benzoic acid, and sorbic acid (Kim et al, 2006). Kimchi ripens rapidly due to the formation of excessive organic acids such as lactic acid and acetic acid, resulting in sourness and texture softening, which affect consumer acceptance as well as the flavor and quality of kimchi (Beuchat and Golden, 1989).…”

Effects of salt type on the metabolites and microbial community in kimchi fermentation

“…The optimal growth and acid production of LAB generally occur at a salt concentration of 2–3% or less ( Hong et al., 2021 ; Kim et al., 2005 ). The salt types used in manufacturing kimchi are mainly purified salt and solar salt; however, other types of salts with various additions, such as roasted salt and bamboo salt, have been used ( Chang et al., 2011 ; Kim and Kim, 2014 ).…”

“…To further investigate the effect of salt concentration on fermented vegetables, we performed a non-targeted metabolite analysis using mass spectrometry along with multivariate statistical analysis ( Lee et al., 2021 ; Seo et al., 2018 ; Yang et al., 2020 ). Although several studies have reported the effect of salt type on kimchi fermentation ( Chang et al., 2011 ; Kim and Kim, 2014 ), few studies have reported the correlation between salt type and corresponding metabolites and microbial community ( Kim et al., 2017 ). Also, previous studies have analyzed the effects of the effects of the addition of purified salt and solar salt to kimchi and the aging period of solar salt on kimchi.…”

Changes in Microbial Community by Salt Content in Kimchi during Fermentation

“…김치 발효에 관여하는 유산균에는 주로 Leuconostoc, Lactobacillus, Lactococcus와 Weissella 속 등이 관여한다 (Park 등, 2001;Jung 등, 2011). 발효 초기 단계에서는 이형발효(heterofermentative) 유산균인 Leuconostoc 속이 중요한 역할을 하고, 동형발효(homofermentative) 유산균인 Lactobacillus는 후기 단계에서 그 역 할을 한다 (Jung 등, 2012 Kim, 2014). 김치의 적당한 소금 농도는 약 2.0~3.0%로 알려져 있으며 (Cho, 1999;Mheen 과 Kwon, 1984), 남부지역처럼 따듯한 지역에서는 발효를 늦추기 위해 첨가량이 많다(3.0~5.0%).…”