This study was conducted to investigate the effects of drying methods for Citrus junos peels on quality characteristics of the hot-water leachate from teabags containing those peels. Fresh peels were hot-air (50℃), cold-air (30℃), or freeze-dried (-45℃), powdered to a size of 40 mesh, packaged with a paper sachet, and then the packaged teabags were leached for 10 min with hot-water (70℃). L*value (lightness) and -a* value (greenness) of the peel powder were the highest in the freeze-dried samples. Soluble solids and titratable acidity of the teabag leachate were in the following order; cold-air, freeze, and hot-air dried samples. Among free sugar contents in all samples, fructose content was the highest, followed by glucose and sucrose. Fructose and glucose contents were not affected by drying methods. There was no significant difference in the flavonoid content among the peels dried using three drying methods. DPPH radical-scavenging activity of the leachate was the highest in the cold-air dried sample. These results suggest that cold-air drying would be an effective method to enhance the quality of hot-water leachate of teabags prepared from C. junos peels.
This study was conducted to develop rice cookies added with young persimmon fruits. Effects of varying amounts (0-12%) of the fruit powder from a young astringent persimmon fruit (picked at July) on the quality characteristics of rice cookies were studied. Ingredients [rice (Oryza sativa subsp. japonica ‘Ilpum’) flours, persimmon (Diospyros kaki Thunb. ‘Cheongdobansi’) powder, sugar, butter, salt, baking powder, egg] were mixed, cut (thickness 3 mm, diameter 35 mm), baked at 170-180℃ for 9 min, cooled, and packaged in polyethylene/nylon bags. The loss rate and spread factor after baking of cookies increased and then decreased with an increase in the amount of fruit powder added. The moisture content and color values (L* and a*) of cookies decreased with an increase in the amount of the persimmon powder added. Phenolic compounds content and DPPH radicals scavenging activity increased with an increase in persimmon powder content; in particular, the DPPH activity of the cookies sharply increased after the addition of 3% persimmon powder. These results suggest that the addition of the young persimmon fruit powder affected the quality characteristics of rice cookies and this fruit powder (approximately 3%) can be utilized as an additive during rice cookie processing.