Abstract: To determine the test method of microorganisms in the blender after cooking. The total microbial count and standard bacteria artificial contamination method were used to evaluate the cleanliness and bacterial eliminating rate in the blender, and the pretreatment method of the test method was optimized. The results showed that the total microbial count reached 10⁷ CFU in 72 h after cooking, and the top rim and lid of the blender were the two most serious places for microbial to grow. The influence of standard bacteria artificial contamination method on the test results of bacterial eliminating rate was compared between soymilk making method and non-soymilk making method. The soymilk making method had a low bacterial eliminating rate, however, its parallelism was good and the data stability was higher. The optimized bacterial eliminating rate method can better reflect the cleanliness of blender in real life scenes.

Key words: Bacterial eliminating rate, Total microbial count, Escherichia coli, Research on testing methods