EFFECT OF HIGH-PRESSURE TREATMENTS ON PEROXIDASE-ACTIVITY, ASCORBIC-ACID CONTENT AND TEXTURE IN GREEN PEAS

Ultra-high isostatic pressure treatment was applied to green peas in o rder to evaluate the possibility of using this process as an alternati ve to blanching. Different operative conditions (magnitude of pressure from 400 to 900 MPa and treatment times of 5 and 10 min) combination with a mild heat treatment at 60 degrees C were examined. The effects of these treatments on peroxidase enzyme activity, ascorbic acid conte nt and texture were studied. While treatment times did not affect the parameters measured, increase in pressure resulted in a higher level o f peroxidase inactivation and retention of ascorbic acid. Pressurized samples did not show differences in texture, although a significant re duction in firmness was observed with respect to fresh peas. Among the conditions tested, 900 MPa for 5 min gave the best results with respe ct to fresh peas (residual peroxidase activity and ascorbic acid conte nt 12% and 82%, respectively), and also in comparison with results rep orted in the literature for the blanching process. These results demon strate that ultra-high pressure is a promising technology for use as a n alternative to blanching.