Determination of flavor precursor compound S-alk(en)yl- l-cysteine sulfoxides by an HPLC method and their distribution in Allium species

Abstract

Listen

Translate article

Pungency precursor compounds, S-methyl (Me), S-2-propenyl (allyl, Al)-, and S-propenyl (Pe)- l-cysteine sulfoxides (CSO), were determined from eight Allium species plants using high performance liquid chromatography after dansyl-Cl derivatization. Allium plants selectively contained two or three kinds of CSOs with varying amounts and proportions, corresponding to their flavors. MeCSO was a major precursor in chive and Chinese chive (0.68–1.85 mg g −1 fresh wt.) and found in all the species examined with less amounts. AlCSO was the major precursor in garlic and giant garlic (3.2–9.8 mg g −1), and was also contained in chive and Chinese chive. PeCSO was the main flavor precursor in onion, green onion, leek, and shallot (0.3–2.2 mg g −1), but also found in chive, Chinese chive, garlic and giant garlic. Garlic and giant garlic contained greatest amounts of total CSO (5.0–11.7 mg g −1), while Chinese chive, dehydrator onion, leek, shallot had moderate amounts (2.0–5.0 mg g −1). Japanese bunching onion, onion (TG 1015Y), and chive leaves contained least amounts of total CSO (<2 mg g −1). S-propyl CSO, however, was not found in any of these species. Based on the composition of the precursors, we could classify the Alliums species into three groups, such as Me-, Al-, and PeCSO dominant groups.