In this study, we investigated the effects of pre-soaking in salt and sugar solution prior to air drying at 50℃ on the characteristics of dried apples. Pre-soaking solutions included single solutions of salt 2% and sugar 2%; and combined solutions of salt 2%+sugar 2% and salt 2%+sugar 5%, respectively. The effects of pre-soaking condition and drying were evaluated in terms of moisture content (MC), water activity, color, antioxidant activity determined by DPPH radical scavenging activity, shear force, microbial contents, and sensory evaluation of apple slices. The control sample without pre-soaking showed the most rapid drying rate; in addition, the single solutions showed higher MC and water activity after drying time of 120 min, as compared to combined solutions. In all samples, MC and water activity showed high correlation coefficients of 0.91 to 0.97; whereas, shear force was negatively correlated with MC and water activity. The single solution of salt 2% showed decrease in change of color, including L, a, and b values, and the number of aerobic bacteria during drying. In addition, highest antioxidant activity and values of sensory preferences were observed in the dried apple pre-soaked in single solution of salt 2%.
This study investigated the antioxidative activities and quality characteristics of gruel as a home meal replacement with Angelica keiskei powder pre-treated by far-infrared radiation or freeze-drying methods. Far-infrared treated Angelica keiskei powder (F-IAP) showed significantly lighter, weaker green, and stronger yellow color values than powder subjected to freezedrying (FAP) (p<0.001). F-IAP showed higher total phenolic compound contents than that of the FAP. ABTS radical scavenging activity of F-IAP was 50.31%, which was significantly higher than that of FAP, at 43.51% (p<0.05). Color values of gruel significantly decreased with increased addition of Angelica keiskei powder (p<0.05). Gruels containing far-infrared treated Angelica keiskei powder (F-IAG) showed higher total phenolic compound contents as well as ABTS radical scavenging activities compared to the gruels containing freeze-dried Angelica keiskei powder (FAG). Gruels containing 5 g of Angelica keiskei powder showed 2.0 to 2.5 times higher antioxidant activities than those containing powder alone due to the presence of other ingredients with antioxidant activities such as black soybean or sweet pumpkin. In the results of sensory evaluation, F-IAG containing more than 5 g of Angelica keiskei powder had higher sweetness and roasted grain flavor, as well as lower bitterness and astringency compared to FAG. Sensory acceptance tests of all samples showed higher scores than 5.0 representing possibilities of successful development of gruels as a home meal replacement containing Angelica keiskei powder.
양파의 예건 방법 및 기간이 저장 중 부패에 미치는 영향을 구명하기 위하여 만생종인 창녕대고 품종을 이용하여 1997년~1998년의 2개년 동안 양파를 수확 후 노지 포장과조립식 간이하우스(통풍) 및 조립식 간이하우스(무통풍)에서 1~3일간 예건 후 저장하여 실험하였다. 예건 기간중의 최고기온은 무 통풍 하우스에서 가장 높았고 노지 포장에서 가장 낮았으며 특히 무통풍 하우스에서 1997년 처리 2일째 및 3일째와 1998년 처리 2일째는 41.6