Study on rapid detection method of β-lactamase in dairy products

The purpose of this study was to establish a rapid detection method for detecting β-lactamase in dairy products.β-lactamase was added to different dairy products, and its detection limit was determined by rapid detection method and cylinder plate method respectively.Influence of storage time and heating treatment to the enzymatic activity of β-lactamase was investigated by durability and stability experiments.The detection limit of β-lactamase in rapid detection method was 1.5×10-4 ～1.6×10-3 U/mL (U/g) , and in cylinder plate method was 2.0×10-5 ～1.6×10-4 U/mL (U/g) .The β-lactamase positive rate of 178 samples detected by rapid detection method and cylinder plate method was identical.It suggested that the sensitivity and accuracy of two methods were similar.Results of durability and stability experiments showed that the influence of storage time to β-lactamase was not significant, but heating treatment decreased the enzymatic activity of β-lactamases obviously.