Changes in antioxidant capacity, levels of soluble sugar, total polyphenol, organosulfur compound and constituents in garlic clove during storage

• Garlic extracts display strong antioxidant capacities.
• The levels of soluble sugar decrease during storage.
• Total polyphenols and organosulfur compounds reach max at 6 and 8 weeks, respectively.
• 18 typical organosulfur compounds are identified by GC–MS.
• Organosulfur compounds play a key role in antioxidant capacities in garlic.

The present study was designed to study the effect of storage duration on changes of antioxidant capacities and bioactive compounds in garlic clove by DPPH and FRAP assays and GC–MS analysis. Both DPPH and FRAP assays displayed that the antioxidant capacities in garlic clove extracts reached maximum values at 8 weeks. The levels of soluble sugar decreased during storage, and the contents of total polyphenols and organosulfur compounds reached maximum value at 6 and 8 weeks, respectively, and then decreased significantly. The GC–MS analysis results of ethyl acetate extract showed that among of the eighteen typical organosulfur compounds, ten compounds reached maximum levels at 8 weeks. The present study indicated that organosulfur compounds in garlic cloves might play a key role in antioxidant capacities due to their positive relationship during storage. The results in this study would provide beneficial information for garlic processing industries and consumers to make full use of garlic during storage.