2017 Volume 34 Issue 4 Pages 202-206
Improvement of aerobic bacteria counts for analysis of powdered beverage with solidified ingredients as an example for food that the physical and chemical natures inhibit the performance of examination was investigated. A 10-fold diluted homogenate prepared by the method of Food Sanitation Law for powdered beverage immediately solidified into a gel, making it hard to use in pour culture. A 100-fold diluted homogenate was prepared instead of 10-fold homogenate to weaken the gelation and was used for examination within 5 min, leading to satisfactory recovery of microorganisms. It was demonstrated that the modified method with a 100-fold diluted homogenate was performed on the same detection limit as the original method. In addition, 200-fold diluted homogenate also was adapted for the examination. The superior methods shown in this study might be applicable to other food having similar nature.