Nutritional quality and volatile flavor substances of “laba” garlic products produced by either soaking or fumigating with acetic acid

Abstract

The quality of garlic (Allium sativum L.) is attributed to nutrients and organosulfur compounds. In this study, the quality of “Laba” garlic with the same degree of greening produced by soaking or fumigating with acetic acid was investigated using fresh garlic as the control. Garlic fumigated with acetic acid exhibited higher soluble solid, monosaccharide, and polyphenol contents. The flavor profiles were significantly distinguished without overlap using the linear discriminant analysis classification model. Thirty volatile compounds were detected in the garlic samples, of which 16 were common among the three garlic samples, while four and five unique compounds were identified in fresh and fumigated garlic, respectively. “Laba” garlic fumigated with acetic acid showed more varieties of allyic compounds and higher contents of thiocycloalka(e)nes than that soaked in acetic acid. In summary, “Laba” garlic produced by fumigation with acetic acid was of higher quality than that produced by soaking in acetic acid. Practical applications “Laba” garlic is made by pickling aged garlic in vinegar. However, green pigment, water-soluble vitamins (including vitamin B and C) and sugars might transfer from garlic to the soaking solution. Therefore, “Laba” garlic was prepared by dry processing, through fumigation with acetic acid. Clarification of quality difference between “Laba” garlic products produced by traditional and dry processing methods will provide useful information for the “Laba” garlic processing industry.