Determination of s-allyl-l-cystein, diallyl disulfide, and total amino acids of black garlic after spontaneous short-term fermentation

Abstract

Garlic (Allium sativum L.) is one of the oldest cultivated plants and has been used throughout the world as a food supplement and a folk medicine for thousands of years. Raw garlic has been processed into a variety of commercial garlic products for consumer convenience. The latest new processing technology, 'spontaneous short-term fermentation', has been developed to process raw garlic into black garlic. The physiologically active effects of garlic have been attributed to its organosulfur compounds. In this study, the proximate compositions and the total amino acid content of raw Namhae garlic and black garlic were determined. The two major organosulfur compounds of garlic, S-allyl-L-cysteine (SAC), and diallyl-disulfide (DADS), were also analyzed using RP-HPLC. The proximate compositions were not different between raw and black garlic. The amount of 13 amino acids was greater in black garlic than in raw garlic among a total of 17 amino acids considered. The black garlic had 2-fold higher levels of SAC and 30-fold higher levels of DADS than the raw garlic. Therefore, it is suggested that consuming black garlic produced by spontaneous short-term fermentation is more effective than consuming raw garlic, in order for consumers to take more physiologically active organosulfur compounds (SAC and DADS), which are the compounds that are good for consumer health.