Popis: |
Endoproteinase and exopeptidase activities were determined in nine commercially available enzyme preparations using synthetic fluorogenic substrates at pH 7.0 and 8.0 and at 37 and 50°C. Four Bacillus (i.e. Protamex, Alcalase 0.6 L, Neutrase and Neutral Protease), three Aspergillus (i.e. Corolase 7092, Fungal Protease and Flavourzyme) and two porcine pancreatic (i.e., PTN 3.0S powder and PTN 3.0S granulated) preparations were analysed. Considerable variations in the endoproteinase, elastase-like, chymotryptic and tryptic activities were observed. Flavourzyme contained high aminopeptidase, while Fungal Protease had high X-prolyl-dipeptidyl-aminopeptidase activity. Significant differences were observed in the characteristics of the WPC hydrolysates generated with the above preparations. Some trends were observed between enzyme complement and hydrolysate characteristics, e.g. enzyme preparations with high exopeptidase activities resulted in hydrolysates having high DH values and low levels of hydrophobic peptides. However, in general it was not possible to directly predict the characteristics of WPC hydrolysates from the endoproteinase and exopeptidase complement in the crude enzyme preparations. |