Changes in the Physicochemical Properties and Sensory Characteristics of Burdock (Arctium lappa) During Repeated Steaming and Drying Procedures

摘要

This study was conducted to investigate changes in the physicochemical, antioxidant, and sensory properties of burdock during 9 repeated rounds of steaming (90°C, 3 h) and drying (60"C, 20 h) procedures. The moisture content decreased from 81.95% to7.64% as the process was repeated. Fresh burdock showed the highest total sugar content, with 518.35 mg/g of soluble sugar, 86% being inulin. The reducing sugar content was the greatest (377.00 mg/g) in burdock that had been processed 3 times. The browncolor continuously intensified, reaching its peak at 7 rounds of processing, and then weakened. Crude saponin content was the highest (6.17%) after the 5th processing. Polyphenol content and antioxidant activity (DPPH, ABTS, FRAP) were the highest at the3rd and 5th procedures, respectively. Repeated processing weakened the grass and root odors and the bitter, astringent, and metallic tastes, whereas it strengthened the sweet and savory odors, caramel flavor, and richness.