Abstract
This study was conducted to determine the effect of far infrared-vacuum drying on the quality changes of Pimpinella bracycarpa, such as drying efficiency (weight loss), color differences, browning degrees, rehydration and sensory evaluation. Wehn Pimpinella bracycarpa was dried for designated time at 5$0^{\circ}C$, 6$0^{\circ}C$ and 7$0^{\circ}C$, drying time of far infrared-vacuum drying was decreased more than 17% compared to that of infrared drying. The color changes increased as drying temperature increased and far infrared-vacuum drying made less color changes than infrared drying. Also, the total microbial counts and the number of yeast and mold were gradually reduced as drying temperature increased and drying time was longer, but there was no significant differences in microbial changes among drying methods. The rehydration rates of Pimpinella bracycarpa increased as drying temperature increased and was better at far infrared-vacuum drying than infrared drying. Also, according to the sensory evaluation after rehydration of Pimpinella bracycarpa, the hihger scores were obtained at lower temperature and far infrared-vacuum drying, especially the color was obtained much hihger score in the far infrared-vacuum drying than infrared drying. Thus, the results showed that drying efficiency and stability of rehydration and color changes was increased and the quality deterioration of Pimpinella bracycarpa could be minimized by using far infrared-vacuum drying.
참나물을 원적외선 건조기와 원적외선-진공건조기를 사용하여 건조할 때 건조조건에 따른 건조속도, 색도, 미생물 변화, 갈변도, 수화복원성 및 관능검사 등 건조참나물의 품질변화에 미치는 영향을 조사하였다. 참나물의 건조속도는 건 조온도를 5$0^{\circ}C$, 6$0^{\circ}C$ 및 7$0^{\circ}C$로 하여 원적외선-진공건조를 하였을 때는 원적외선 건조한 경 우보다 건조시간이 약 17%이상 단축되었다. 색도변화는 건조온도가 높을수록 증가되었으며 원적외선진공건조가 원적외선보다 그 변화율이 작았다. 건조시간에 따른 참나물의 미생물변 화는 건조온도가 높을수록 그리고 건조시간이 길어질수록 감소하였으나 건조방법에는 큰 영 향을 받지 않았다. 건조방법과 건조온도에 따른 참나물의 수화복원성은 원적외선-진공건조 시료가 원적외선 건조시료보다 재수화 특성값이 높았으며, 특히 건조온도가 높을수록 복원 률이 우수하였다. 재수화 후의 관능적 품질은 낮은 온도에서 그리고 원적외선 건조 참나물 보다 원적외선-진공건조 참나물이 높은 점수를 얻었으며, 특히 관능적 색도면에서는 원적외 선 건조보다 원적외선-진공건조를 행한 경우에 훨씬 좋은 점수를 나타내었다. 따라서 원적 외선-진공건조를 사용할 경우 원적외선 단독보다는 건조 효율이 증대되며, 복원성과 색도의 안전성을 증진시킴으로써 참나물의 품질저하를 최소화할 수 있었다.
