Simple test for differentiation between fresh pork and frozen/thawed pork

Enzyme profile of the exudates from fresh and frozen/thawed pork has been assayed by using a semi-quantitative method (APIZYM). Only three enzymes (esterase-lipase, ?-glucuronidase and α-glucosidase) showed significant differences (P < 0·01) between fresh and frozen/thawed pork. Different storage conditions were tested (freezing temperature: -10 to -60°C for 13 days and time of storage: 11 to 54 days at -18°C) but no significant differences were found among them. The APIZYM system would constitute a simple method for detecting frozen/thawed pork.