The cysteine proteinase from Micrococcus sp. INIA 528
was added at three
concentrations to pasteurized cows' milk to study its effect on the
ripening process
of Hispanico cheese. Dry matter was higher in whey from experimental cheeses
than
in whey from control cheese manufactured from milk with no added proteinase.
No
differences in cheese proteolysis were found 24 h
after manufacture. Residual αs- and
β-caseins were significantly lower, and N soluble at
pH 4·6 and in trichloroacetic acid
significantly higher, in experimental cheeses than in control cheese from
day 15.
Hydrophobic and hydrophilic peptides in the water-soluble fraction of cheese
measured by absorption at 280 nm were significantly higher in experimental
cheeses
than in control cheese from days 1 and 15 respectively. Texture was less
firm in
experimental than control cheese from day 30. Bitterness, detected in cheese
with the
highest levels of added cysteine proteinase, adversely affected cheese
flavour.
Flavour intensity was significantly higher from day 30 in cheeses with
added
proteinase than in control cheese.