The quality characteristics of ginger powder manufactured with different numbers of steaming and drying treatments were evaluated. The moisture content of the ginger powder ranged from 6.51% to 7.26%, with the nine-time treatment showing the lowest and the six-time treatment showing the highest values (p<0.001). The crude protein content ranged from 2.36% to 4.11%, with the control being the highest and the three-times-treated being the lowest. The crude fat content ranged from 6.85% to 7.82%, with the control being the highest and the 9-times treatment being the lowest. Ash content was highest in the control, followed by the 6-, 3-, and 9-time steaming treatments. The brightness and yellowness of ginger powder, according to the number of steaming treatments, were highest in the control and decreased as the number of treatments increased. The redness ranged from 3.63 to 7.26, with the 9-treatment showing the highest value. The steamed ginger powder showed as increase in the antioxidant activity, the total polyphenol, total flavonoid, DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP activity according to the number of steaming. The results showed that the Gujeonggupo (9-times treatment) ginger powder had lower moisture, ash, crude fat content, and pH than the control group. In terms of color, the lightness and yellowness were low, but the redness was high, and it showed high antioxidant activity.
Kim et al. (Fri,) studied this question.