Studies were carried out to evaluate the efficiency of removal of beta
-lactoglobulin from cheese whey using biospecific subunit exchange aff
inity chromatography (BSEAC). The highest percent recovery (78.28%) wa
s achieved at a pH of 4.6. Using hydrophobic interaction chromatograph
y (HIC) and particle size distribution (PSD), aggregation phenomena, t
he basis for the selective extraction of beta-lactoglobulin, was exami
ned. While HIC proved to be inconclusive, a general pattern was obtain
ed. PSD is a light scattering technique which can be utilized to deter
mine average particle size (nm) suspended in a solution. A distinct pr
ofile evolved when particle size was plotted against pH for the two ex
perimental temperatures. While beta-lactoglobulin has a tendency to te
tramize between pH 3.7 and 5.2, it was observed that the highest degre
e of aggregation was at the isoelectric point (pH 5.2). At pH 4.6 the
aggregates had an average size of 240 nm while at pH 5.2 the average w
as 340 nm (4 degrees C). It was proposed that the separation efficienc
y of beta-lactoglobulin could be optimized if: 1) aggregate size was m
aximized through pH manipulation (pH 5.2, 4 degrees C) and 2) a suppor
t matrix that would accomodate complexes in excess of 340 nm was utili
zed.