Application of chitosan for recovery of protein and
fat from cheese whey
Fernandez and Fox [92] reported the use of chitosan
to remove proteins and peptides from cheese whey.
Urea-PAGE (polyacrylamide gel electroplorosis)
showed that chitosan gave good fractionation of watersoluble
extract at pH 2, 3 and 4. At pH 5, 6 and 7, most
of the nitrogen of the water-soluble extract remained
soluble in 0.02% chitosan. However, when the pH was
reduced stepwise, the best fractionation was obtained at
pH 4.0. The addition of 0.01±0.016% chitosan to cheddar
cheese whey at pH 4.5 almost completely removed
the milkfat globule membrane fragments prior to ultra-
®ltration [33]. Since the pKa of the amino group of
glucosamine residues is about 6.3, chitosan is extremely
positively charged at pH 4.5. This facilitates electrostatic
interaction between chitosan and the negatively
charged milkfat globule membrane fragments. This
method could be used as an industrially feasible process
to remove lipids from cheese whey [33]. Coagulation of