COMPARISON OF POUR AND SURFACE PLATE METHODS FOR DETERMINATION OF BACTERIAL COUNTS

Abstract

Tests comparing the pour and surface plate methods for determination of bacterial numbers in ice, in water, and on processed birds in poultry plants showed that counts for the latter technique were about 70% and 80% higher than those for the former at incubation temperatures of 0 °C and 22–25 °C, respectively. Recovery studies with pure cultures indicated that the difference was related to both type and strain of bacteria. The pseudomonads as a group did not contribute to the difference, whereas some but not all of the achromobacter tested contributed markedly.