Spiral plate count method for the examination of raw and pasteurized milk

Abstract

The spiral plate count method (SPLPC) was compared with the standard plate count (SPC) method by examining 201 samples of raw and pasteurized milk. Although the means of the two methods differed significantly at α=0.01, the difference was <10% and was not considered to be of any practical importance. The pooled replicate variances of both methods were <0.003, indicating good agreement between duplicate plates, with the variance of the SPLPC slightly less than that of the SPC. The authors believe this study indicates that the SPLPC could be substituted for the SPC in the bacteriological examination of milk.