Study on Rheological and Sensory Properties of Cooked Rices -I. Changes in Flavor and Appearance of Cooked Rices during Storge-

쌀 품종에 따른 쌀밥의 물리적 및 관능적 특성 연구 -I. 저장중 쌀밥의 풍미 및 겉모양의 변화-

Three rice varieties of Akibare (japonica), Milyang 30 (indica) and Taebaeg (indica) were investiated for sensory and physical qualities of cooked rices during storage at the temperature range of $4^{\circ}C$ and $70^{\circ}C$ for 25 hours. The qualities studied were sensory attributes of odor, taste and appearance which were evaluated by multiple comparison method. The other properties were size of rice granule and separation Property of individual cooked rices in water. The sensory results showed that all of the descriptions except moldy odor and oily taste were scored higher values for cooked rices of Akibare than those values of Milyang 30 and Taebaeg. It was found that storage of cooked rices at various temperatures resulted a significant decrease in most of sensory qualities except moldy odor and oily taste which were rather increased. The quality change was more affected at storage at low temperature, particularly at $4^{\circ}C$, than at higher temperatures. The property of individual separation of cooked rices in water for freshly cooked rices showed that Akibare was separated 44.4% after 1 minute shaking while Milyang 30 and Taebaeg had the higher separation value of 53.1%, and 51.0%, respectively. This characteristic was noticeably reduced after 3 hours storage and then steady increased during further storage. It was also found that the separation percent was generality increased as the storage temperature increased from $4^{\circ}$ to $70^{\circ}C$.

일반계(아끼바레)와 다수계(밀양 30, 태백)의 취반된 쌀밥이 온도별로 저장하는 동안 쌀밥의 풀어짐성과 냄새, 맛, 겉모양과 같은 관능적 성질이 변화함을 비교하였다. 그 결과 취반후의 쌀밥크기는 아끼바레가 가장 많이 증가하였으며 물속에서의 풀어짐성은 다수계가 아끼바레보다 높았다. 저장시간이 경과함에 따라 풀어짐성은 전반적으로 3시간 저장시 현저히 감소하였다가 서서히 증가하였으며 이러한 경향은 낮은온도$(4^{\circ}C)$에서 더욱 현저하였다. 쌀밥의 냄새는 아끼바레가 단냄새와 구수한 냄새에서 다수계보다 높았으나 곰팡이냄새는 낮았다. 맛은 구수한 맛과 느끼한 맛에서는 품종간에 큰 차이가 없었으나 단만은 아끼바레가 높은 강도를 보여주었다. 온도별 저장에 따른 변화는 전반적으로 구수한 냄새와 단냄새가 시간이 경과함에 따라 감소하였으며 곰팡이 냄새는 오히려 증가함을 보여주었다. 맛에서도 구수한 맛과 단맛의 현저한 감소가 평가되었다. 한편 겉모양에서는 아끼바레가 다수계보다 윤택하였으며 이러한 성질은 저장하면서 서서히 감소함을 보여주었다.