Resazurin 환원법을 응용한 돈육의 신속 미생물 검사법에 관한 연구

Abstract

본 연구는 실험방법이 간단하고 분석비용이 저렴하며, 단시간내에 세균수를 측정할 수 있는 현장적용 가능한 방법을 확립하기 위하여 냉장우육의 총균수를 표준평판배양법과 배양온도를 25<TEX>$^{\circ}C$</TEX>, 30<TEX>$^{\circ}C$</TEX>, 35<TEX>$^{\circ}C$</TEX> 별로 레자주린 환원색과 환원시간을 측정하여 상관관계를 산출하였다. 연구결과를 보면, 총균수(25<TEX>$^{\circ}C$</TEX>/72시간, Y)와 레자주린 환원시간(X)과의 상관계수는 RRT (Resazurin reduction test) 배양온도가 25<TEX>$^{\circ}C$</TEX>와 30<TEX>$^{\circ}C$</TEX>, 환원색은 청색에서 분홍색으로 변할 때가 각각 -0.95와 -0.94로서 가장 높았다. 상관계수와 환원시간을 감안할 때 RRT 배양온도는 30<TEX>$^{\circ}C$</TEX>가 적합하였으며, 이때 회귀방정식은 Y = -0.4386X+7.7870이었으며, 돼지고기의 총균수가 <TEX>$10^2$</TEX>, <TEX>$10^3$</TEX>, <TEX>$10^4$</TEX>cfu/<TEX>$cm^2$</TEX>일 경우 검사시간은 13.2시간, 10.9시간, 8.6시간이었다. 총균수(30<TEX>$^{\circ}C$</TEX>/72시간, Y)와 레자주린 환원시간(X)과의 상관계수는 RRT 배양온도가 30<TEX>$^{\circ}C$</TEX>, 환원색은 청색에서 분홍색으로 변할 때가 -0.93으로서 가장 높았다. 이때 회귀방정식은 Y=-0.4171X+7.5540이었으며, 돼지고기의 총균수가 <TEX>$10^2$</TEX>, <TEX>$10^3$</TEX>, <TEX>$10^4$</TEX> cfu/<TEX>$cm^2$</TEX>일 경우 검사시간은 13.3시간, 10.9시간, 8.5시간이었다. 총균수(35<TEX>$^{\circ}C$</TEX>/48시간, Y)와 레자주린 환원시간(X)과의 상관계수는 RRT 배양온도가 30<TEX>$^{\circ}C$</TEX>, 환원색은 청색에서 분홍색으로 변할 때가 -0.93으로서 가장 높았다. 이때 회귀방정식은 Y=-0.3514X + 6.7513이었으며, 돼지고기의 총균수가 <TEX>$10^2$</TEX>, <TEX>$10^3$</TEX>, <TEX>$10^4$</TEX>cfu/<TEX>$cm^2$</TEX>일 경우 검사시간은 13.5시간, 10.7시간, 7.8시간이었다. In order to search for reliable rapid methods of estimating bacterial counts in pork, this study was tried to measure resazurin reduction time which is simple in experimental method, low in analytical cost, able to estimate bacterial count within short time. The results were summarized as follows; Correlation coefficient between initial bacterial log count(25<TEX>$^{\circ}C$</TEX>/72hr, Y) and resazurin reduction time(X) from blue color to pink color during incubation at 25<TEX>$^{\circ}C$</TEX> and 30<TEX>$^{\circ}C$</TEX> was higher than other conditions as -0.95 and -0.94, respectively. Considering correlation coefficient and reduction time, incubation temperature was compatible at 30<TEX>$^{\circ}C$</TEX>, and regression equation(RE) was Y = -0.4386X + 7.7870. At a bacterial load of <TEX>$10^2$</TEX>cfu/<TEX>$cm^2$</TEX>, <TEX>$10^3$</TEX>cfu/<TEX>$cm^2$</TEX> and <TEX>$10^4$</TEX>cfu/<TEX>$cm^2$</TEX> in pork, reduction time was 13.2hr, 10.9hr and 8.6hr, respectively. Correlation coefficient between initial bacterial log count(30<TEX>$^{\circ}C$</TEX>/72hr, Y) and resazurin reduction time(X) from blue color to pink color during incubation at 30<TEX>$^{\circ}C$</TEX> was highest among other conditions as -0.93, and RE was Y = -0.4171X + 7.5540. At a bacterial load of <TEX>$10^2$</TEX>cfu/<TEX>$cm^2$</TEX>, <TEX>$10^3</TEX>cfu/<TEX>$cm^2$</TEX> and <TEX>$10^4</TEX>cfu/<TEX>$cm^2$</TEX> in pork, reduction time was 13.3hr, 10.9hr and 8.5hr, respectively. Correlation coefficient between initial bacterial log count(35<TEX>$^{\circ}C$</TEX>/72hr, Y) and resazurin reduction time(X) from blue color to pink color during incubation at 30<TEX>$^{\circ}C$</TEX> was highest among other conditions as -0.93, and RE was Y = -0.3514X + 6.7513. At a bacterial load of <TEX>$10^2$</TEX>cfu/<TEX>$cm^2$</TEX>, <TEX>$10^3$</TEX>cfu/<TEX>$cm^2$</TEX> and <TEX>$10^4$</TEX>cfu/<TEX>$cm^2$</TEX> in pork, reduction time was 13.5hr, 10.7hr and 7.8hr, respectively.