EFFECT OF CARBON-DIOXIDE ON ANTHOCYANINS, PHENYLALANINE AMMONIA-LYASEAND GLUCOSYLTRANSFERASE IN THE ARILS OF STORED POMEGRANATES

Wonderful' Pomegranates (Punica granatum L.) were placed in jars venti lated continuously with air or air enriched with 10 or 20 kPa CO2 at 1 0 degrees C for 6 weeks. Samples were taken initially and after 1, 2, 4, and 6 weeks, and postharvest quality attributes were measured. The arils of the pomegranates stored in air were deeper red than the initi al controls and than those stored in CO2-enriched atmospheres. This in creased color was associated with increased anthocyanin concentration. Arils from fruit stored in air enriched with 10 kPa CO2 had a lower a nthocyanin concentration than air-stored fruit, and atmospheres enrich ed with 20 kPa CO2 had even lower levels, possibly from suppressed ant hocyanin biosynthesis. Anthocyanin concentration correlated well with the activity of phenylalanine ammonia lyase but not with glucosyltrans ferase activity. Moderate CO2 atmospheres (10 kPa) prolong the storage life and maintain quality of pomegranates, including adequate red col or intensity of the arils.