The simple preparation and determination of antioxidant activity of black garlic

To obtain the easy way for preparation of family black garlic and investigate the effects of fermentation time on the chemical composition and antioxidant activity of black garlic, the content of moisture, sugar and total phenolic, hydroxyl radicals scavenging activity, DPPH radical scavenging activity were determined. The results suggested that under the condition of fermentation temperature in range of 55 ℃ to 60 ℃, relative humidity range from 85% to 95%, the moisture content of black garlic decreased significantly during the fermentation process, while sugar and polyphenols content were increased. The moisture, sugar and polyphenols content of fresh garlic was 68.1%, 2.6%, 1.66 mg/g. The components of black garlic fermented for 30 days were 36.3%, 10.7%, 6.81 mg/g, respectively. Besides, the black garlic had a higher free radical scavenging ability in comparison with fresh garlic. Its aqueous samples exhibited increased DPPH and hydroxyl radicals scavenging activities with increased fermentation time. The inhibition of hydroxyl radicals and DPPH radicals increased from26.4%, 54.6% to 26.4% and 85.3%,respectively. Results of this study illustrates that preparation method of family black garlic is simple, and the black garlic has a unique mouthfeel and great antioxidant capacity.