Optimizing of High Throughput Determination of Protease Activity in Milk Using Folin-phenol Method
[Objective]To optimize the conditions for the determination of protease activity in milk using the national standard method-Folin-phenol method.[Method]By measuring the protease activity in milk,the influence of various experimental parameters on the results was compared and analyzed.[Result]When using an enzyme-linked immunosorbent assay(ELISA)reader for measurement,the color retention time should be more than 15 minutes,and a sample of 350 μL.When the concentration of Folin reagent is 0.33~0.5 mol/L,the absorbance constant K value of the standard curve meets the requirements.[Conclusion]When detecting protease activity in milk,it is necessary to control the color retention time,sampling volume,and clarity of the sample solution.After the color reaction is fully completed,the system of the standard solution and sample solution has stabilized,and there is no significant change in the absorbance value within 1 hour of further insulation or room temperature storage,which has no significant impact on the results.