Flavor compound profiles and enhancement strategies in the kimchi-making process

Lacto-fermentation is a traditional preservation technique that improves the texture and flavor of vegetables. In Korean cuisine, kimchi is highly regarded for its captivating and complex aroma, which appeals to both local and global palates. However, there is no comprehensive list of flavor compounds previously reported in a review. This review aims to illustrate the flavor compounds of kimchi, their origins, and the factors that influence their regulation. Key steps in the kimchi-making process, including the selection of raw materials, salting, mixing and fermentation are detailed. Various flavor compounds such as sugar, organic acids, free amino acids and volatile compounds are discussed in relation to their main origin and roles in flavor development during the kimchi-making process. Furthermore, the review highlights how intrinsic and extrinsic factors such as the addition of minor ingredients, salinity, temperature, starter culture, pH and fermentation time can be manipulated to optimize flavor profiles. The growth of microbes might be encouraged, to produce specific metabolites for a desired taste and aroma that meet the preferences of end consumers. Further research investigations are required to address potential sanitary issues and ways of controlling them, the benefits of adding starter culture to enhance specific flavors, and to better exploit the potential for innovation of this traditional fermented food. This review is expected to be valuable for understanding the interactions between ingredients, microbial communities and fermentation conditions, providing insight into creating kimchi that meets consumer preferences while preserving its cultural heritage.