MECHANISM OF SURFACE WHITE DISCOLORATION OF PEELED (MINIMALLY PROCESSED) CARROTS DURING STORAGE

A proposed mechanism of white discoloration development on peeled carrots included both physical and physiological responses to wounding. The physical response is a color change due to reversible surface dehydration. This study was performed at 2.5 and 10 degrees C using a model system controlling relative humidity, at 33, 75 or 98%, and a commercial system with low-density polyethylene (LDPE) plastic film bags. The rate of surface discoloration increased with decreasing RH. When excess surface moisture was left on peeled carrots, rates of white development decreased sharply at all RH compared with a dewetted control. The same effects were observed on peeled carrots stored in LDPE bags. Carrots partially regained their original color when water-dipped, due to reversal of the physical response component.