## 1 Introduction  
Kimchi is a traditional Korean fermented vegetable made by fermenting salted cabbage, radish, and cucumber with various spices, including red pepper powder, garlic, ginger, and other ingredients [1]. Natural fermentation with unsterilized raw materials leads to the growth of various microorganisms, including lactic acid bacteria (LAB), resulting in inconsistent quality of kimchi, which may hamper the commercial production of high-quality products [2, 3]. The use of starter cultures in the manufacture of kimchi has been considered an alternative to solve these problems [4]. Applying a starter culture to kimchi has several advantages, such as uniform quality, enhanced sensory characteristics, extended shelf-life, and functional properties of the kimchi product [5, 6]. _Luconsac_ spp. are the dominant species present in the early phase of kimchi fermentation at low temperatures; _Le. mesenteroides_ and _Le. citream_ have been used as industrial starters since the early 2000s [7, 8]. However, despite their excellent role as starters, they are not considered as health-promoting probiotics because of their absence of resistance to acid and bile salt and low colonization capacity in the large intestine [9]. Thereby, in order to manufacture health-promoting kimchi products, the development of a probiotic starter that can be used as an alternative of _Luconostoc_ spp. is required. LAB are present in traditional fermented foods as major starter cultures and are commonly used as health-promoting probiotics. A report by the World Health Organization(WHO) defined probiotics as \"live microorganisms which when administered in adequate amounts confer a health benefit on the host [10; 11]\". Fermented foods can be used as delivery vehicles for probiotics [12; 13]. A previous study reported that consumption of not only pure probiotics but also foods fermented using the same probiotic resulted in equal levels of functionality in piglets; administration of _Propionibacterium freudereichii_ in the form of bacteria cells and fermented cheese increased the population of Propionibacteria and the levels of total short-chain fatty acids in feces, and they provided anti-inflammatory activity [14]. Therefore, it is desirable to develop LAB that can be used as health-promoting starters and their application to produce functional fermented foods. As for kimchi, the development of probiotic starters has been a leading interest among microbiologists to maintain product quality and to improve the health-promoting effects of kimchi [2]. For this purpose, researchers have developed various LAB as probiotic starters, such as _Bifidobacterium_ spp. producing conjugated linoleic acid [15] and _Lactobacillus_ spp. producing \(\gamma\)-aminobutyric acid (GABA) [16]. Additionally, for the same goal, mixed starter cultures have been employed to improve the sensory quality and anticancer and antioxidant activities of kimchi [17]. However, it has been difficult for the kimchi industries to find a successful commercialization case of probiotic starter to date. After investigation of these studies as well as communication with manufacturers, we concluded that those probiotic candidates providing health-promoting effects lack suitable starter properties essential for economical production in the industry. Briefly, a candidate strain of health benefit exhibited little or no growth in kimchi, and another probiotic resulted in a quality loss after fermentation because it produced off-flavor metabolites. Based on these findings, we propose the following requirements that the probiotic candidates should meet: the probiotic must (i) grow well in a kimchi environment containing various constituents, such as garlic and ginger; (ii) grow well at low temperature; (iii) prevent over-ripening by generating optimal concentrations of organic acids; (iv) provide favorable taste and aroma of kimchi; and (v) possess health-promoting properties.