Abstract
This study was performed to develop the method of differentiation fresh and frozen meat by using the measurement of mitochondrial malate dehydrogenase. The principle of this experiment is based on the fact the enzyme proteins associated with mitochondria membrane could be released by freezing. The methods were studied by measurements of protein concentration of meat press juice, WHC (water-holding capacity), drip loss and mitochondrial malate dehydrogenase enzyme activity. Samples were stored at 4$^{\circ}C$ and -18$^{\circ}C$ during storage period, respectively. Protein concentration of meat press juice was ranged from 8.5 mg/mL to 12.7 mg/mL and increased by freezing below at -18$^{\circ}C$(p<0.05). The WHC was not significantly different between fresh meat and frozen chicken meat (p＞0.05). The amount of drip loss of fresh and frozen chicken meat at 4$^{\circ}C$ and -18$^{\circ}C$ was not significantly different (p＞0.05). Mitochondrial malate dehydrogenase activity of frozen meat (-18$^{\circ}C$) was significantly higher (p＜0.05) than that of fresh meat. Also, enzyme activity of frozen meat was maintained at the same level after 3 minutes reaction. But fresh meat had not this reaction. From these results, it suggests that mitochondrial malate dehydrogenase can be used as a promising enzyme to differentiate between fresh and frozen meat.
본 연구는 미토콘드리아 malate dehydrogenase활성을 이용하여 냉장계육과 냉동계육의 판별법을 개발하기 위하여 실시되었다. 단백질의 함량은 8.5mg/mL에서 12.7mg/mL 범위로 나타났으며, 동일 저장 기간 동안의 온도 별 차이점은 모든 부위에서 1일에서 15일 저장기간이 길어짐에 따라 단백질함량이 늘어나는 경향을 보인다. 냉장육의 보수력은 저장 기간 1일 60.5%에서 15일 33.9%로 감소하였으며 유의적 차이는 없었다(p＞0.05). 냉장계육과 냉동계육은 저장 기간이 길어짐에 따라 육즙손실량이 증가하였으며 유의적 차이는 없었다.(p＞0.05). 냉장계육의 육즙손실량이 냉동계육의 육즙손실량보다 낮게 나타났다. 냉장계육과 냉동계육 간의 mitochondrial malate dehydrogenase의 활성은 냉동계육이 냉장계육보다 효소활성이 높게 나타났다. 따라서 본 연구결과로부터 mitochondrial malate dehydrogenase의 활성 여부로 계육의 냉장, 냉동 유무를 판별하는데 유효한 지표로 사용 가능한 것으로 사료되었다.
