Changes in Quality of Mulberry Depending on Distribution and Storage Temperature

For the investigation of the quality loss of mulberry during distribution, the deterioration rate, microorganism growth, and sensory quality of mulberry kept at 20, 10 and $0^{\circ}C$, respectively, were investigated. Based on the results, the optimum temperature for extending the freshness of mulberry was examined in the temperature range of -1.5 to $1.5^{\circ}C$. The level of mold in the mulberry kept at 20 and $10^{\circ}C$, respectively, was much higher than that kept at $0^{\circ}C$. The quality of the mulberry deteriorated seriously after two days at $20^{\circ}C$, after six days at $10^{\circ}C$, and after 12 days at $0^{\circ}C$. The marketability of mulberry as determined via sensory evaluation was much more prolonged by decreasing the keeping temperature from 20 to $0^{\circ}C$. To extend the freshness of mulberry using these results, the optimum temperature was evaluated at the range of -1.5 to $1.5^{\circ}C$ for 25 days. During storage, the changes in the color and pH of the berry were not significantly different by storage temperature, but the microbial levels and deterioration rate increased in the order of 1.5, 0, and $-1.5^{\circ}C$. In particular, the firmness of the mulberry decreased rapidly at $1.5^{\circ}C$, showing a significant difference from the others. The titratable acidity and sugar contents decreased gradually at all the applied temperatures. The anthocyanin content decreased sharply at $1.5^{\circ}C$ but gently changed at $-1.5^{\circ}C$. Through the sensory results of this study, it was adjudged that the marketability of mulberry could be maintained about 0.7 times at $1.5^{\circ}C$ and 1.3 times at $-1.5^{\circ}C$ compared with the marketability at $0^{\circ}C$, respectively.

유통 및 저장 온도에 따른 오디의 품질의 변화

오디의 유통 온도에 따른 품질변화 연구로 오디를 $20^{\circ}C$, $10^{\circ}C$ 및 $0^{\circ}C$에서 방치하면서 온도에 따른 미생물, 변질율 및 관능적 품질의 변화를 조사하였고, 이를 바탕으로 품질 유지기간을 연장키 위한 적정 저온저장 온도를 설정키 위해 오디를 재차 $1.5^{\circ}C$, $0^{\circ}C$ 및 $-1.5^{\circ}C$에 각각 저장하면서 색도, 미생물, 변질율, 경도, pH, 산도, 당도, 안토시아닌과 관능적 품질을 평가하였다. 유통온도에 따른 품질 변화 조사 결과 $20^{\circ}C$와 $10^{\circ}C$에서는 각각 2일 및 6일째, $0^{\circ}C$에선 12일째에 완전히 변질되었으며 관능적 평가에 의한 상품성은 $20^{\circ}C$, $10^{\circ}C$ 및 $0^{\circ}C$에서 각각 1일, 4일 및 12일간 유지되었다. 오디를 $1.5^{\circ}C$, $0^{\circ}C$ 및 $-1.5^{\circ}C$에 각각 저장하였던바 총 균수, 곰팡이 수 및 변질율은 $-1.5^{\circ}C$ < $0^{\circ}C$ < $1.5^{\circ}C$ 순으로 높았다. 저장온도별 경도 및 안토시아닌 변화는 $-1.5^{\circ}C$에서 가장 적었다. 적정산도와 가용성고형물 함량은 전반적으로 감소 하였으며 저장온도에 따른 차이는 뚜렷하지 않았다. 저장온도에 따른 오디의 관능적 상품성 유지기간은 $0^{\circ}C$를 기준으로 $1.5^{\circ}C$에서는 0.7배 정도로 짧아진 반면 $-1.5^{\circ}C$에서는 1.3배정도 연장되었다.