Nm. Kinghorn et al., COMPARISON OF CAPILLARY ELECTROPHORESIS WITH TRADITIONAL METHODS TO ANALYZE BOVINE WHEY PROTEINS, Journal of chromatography, 700(1-2), 1995, pp. 111-123
The separation of the four major whey proteins by sodium dodecyl sulph
ate (SDS)-capillary gel electrophoresis (CGE) is described. Whilst com
mercially purified whey proteins could be analysed using the recommend
ed protocol, the more complex nature of an acid whey and a reconstitut
ed whey protein concentrate (WPC) powder necessitated considerable ref
inement of the CGE sample buffer. Individual whey proteins in the acid
whey and WPC samples were then also separated and quantitated using c
apillary zone electrophoresis, polyacrylamide gel electrophoresis (PAG
E) and HPLC methods and the results were compared. The values obtained
for alpha-lactalbumin (alpha-Lac) and beta-lactoglobulin (beta-Lg) we
re consistent throughout the various methods, although size-exclusion
HPLC, SDS-PAGE and SDS-CGE could not separate the two beta-Lg variants
or the glycosylated form of alpha-Lac from the beta-Lg. There was con
siderable variation in the values for the bovine serum albumin and imm
unoglobulin determined by the different methods and it was concluded t
hat none of the methods could satisfactorily quantitate all four whey
proteins.