A clarifying reagent and microplate-based method for the high-throughput analysis of lipase activity in milk

Lipases play an important dual role in the dairy industry. Lipases improve quality but cause deterioration and changes in quality during the processing and storage of dairy products. Therefore, a rapid and sensitive method for determining lipase activity is needed. A new reagent, called a ‘Clarifying Buffer’, was developed for the clarification of opaque milk and the direct detection of lipase activity in milk using spectrophotometry. The present study successfully used a microplate-based method to analyze lipase activity in milk products. The lipase activities of raw milk samples subjected to different heat treatments were evaluated using the new method. The new method was sensitive to the activity of trace lipase in milk samples treated at 135 °C for 5, 10, and 30 s.