In order to search for reliable rapid methods of estimating bacterial counts in raw milk, 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;
Regression equation(RE) between resazurin reduction time(X) from blue color to bluish purple color during incubation at 15℃, 30℃ and 35℃ and initial bacterial log count(Y) was Y = -0.0852X + 6.495, Y = -0.3208X + 6.474 and Y = -0.3101X + 6.102, with a correlation coefficient of -0.49, -0.65 and -0.51, respectively. The times required to obtain results were 5.9 to 29.7hr, 1.5 to 7.6hr and 0.3 to 6.7hr, respectively.
RE between resazurin reduction time(X) from blue color to purple color during incubation at 15℃, 30℃ and 35℃ and initial bacterial log count(Y) was Y = -0.0643X + 6.289, Y = -0.2894X + 6.789 and Y = -0.3343X + 6.732, with a correlation coefficient of -0.64, -0.80 and -0.74, respectively. The times required to obtain results were 4.4 to 34.7hr, 2.7 to 9.7hr and 2.2 to 8.1hr, respectively.
RE between resazurin reduction time(X) from blue color to pink color during incubation at 15℃, 30℃ and 35℃ and initial bacterial log count(Y) was Y = -0.0505X + 6.171, Y = -0.2606X + 7.014 and Y = -0.3148X + 7.044, with a correlation coefficient of -0.64, -0.83 and -0.77, respectively. The times required to obtain results were 3.6 to 45.2hr, 3.9 to 11.7hr and 3.3 to 9.6hr, respectively.
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