Changes in Chemical Components and Antioxidant Activity of Dried Jujube with Different Aging Temperatures and Durations

This study was conducted to investigate the changes in chemical components and antioxidant activities of dried jujube ( Miller) with different aging temperatures (, , and ) and durations (5 days, 10 days, 15 days, 30 days, and 50 days). The browning index increased from 0.124 to 1.998 with increased aging temperature and duration. As aging duration increased, fructose, glucose, and sucrose content decreased from 24.96% to 4.96%, from 22.23% to 4.41%, and from 18.41% to 0%, respectively. Reducing sugar content decreased from 351.52 mg/g to 155.96 mg/g as aging temperature and duration increased. Total acidity slightly increased from 1.61 to 3.13%. 5-Hydroxymethyl-2-furaldehyde increased from 0.002 mg/g to 38.84 mg/g, respectively. As aging temperature and duration increased, total polyphenol content increased from 15.98 mg/g to 38.61 mg/g. DPPH and ABTS radical scavenging activities increased from 4.03 mg trolox eq/g to 22.22 mg trolox eq/g, and from 2.11 mg ascorbic acid eq/g to 13.39 mg ascorbic acid eq/g, respectively. Reducing power increased rapidly in the first stage and then slowly increased afterward.