1985 Volume 26 Issue 5 Pages 477-482_1
An automatic colony counter (ACC), Artek 880, was compared with the manual technique for accurate and rapid evaluation of the viable bacterial counts in foods.
For 30 to 300 colonies on a plate, from either pure culture strains or raw milk samples, the accuracy of repetition of ACC and personal errors in the manual technique almost satisfied the requirements of Standard Methods for the Examination of Dairy Products (14th ed.) recommended by the American Public Health Association.
The correlation coefficient between ACC counts and manual counts of pure culture strains and raw milk samples were 0.985 and 0.972, respectively, and the slopes of regression lines were 0.903 and 0.942, respectively. Furthermore, acceptable arithmetic mean counts by ACC (within ±10% of the corresponding mean manual counts) were 74% and 46%, respectively.
These results indicated that ACC is useful for routine work on large numbers of samples in food quality control.
