Abstract
Total whey protein was considered to be useful for the diagnosis of the type of Mastitis. Two simple methods were devised to determine total whey protein.
Bromophenol blue (BPB) tube method (temporary name): Mix 0.5ml of 0.2M acetic acid buffer solution, pH4.0, and 0.5ml of milk Centrifuge at 2, 000rpm for 5minutes Isolate whey. Dilute whey 10-20times with acetic acid buffer solution. Mix 1ml of diluted whey and 4.0ml of BPB solution (dissolve 5mg of BPB with 100ml of 0.2M citrate-HCI buffer solutionpH3.0). Determine with spectrophotometer at wavelength of 610μm.
BPB filter paper method (temporary name): Mix 0.2M acetic acid buffer solution, pH4.0, and an equal volume ofmilk. Add 5μl of mixed solution to BPB filter paper (dissolve 100mg of BPB with 100ml of 1.0% citrate solution. Dip a piece of filter paper in the solution and dry). Compare the color and yellow ring size with the standard (made with bovine serum albumin).
