Pectin Changes in the Ripening of Irradiated and Stored Strawberries

SUMMARY: Strawberries of the “Red Gauntlet” variety picked at two different stages of maturation were irradiated with a 60 Co source at 200 krads. After irradiation the fruits were stored in a refrigerated cell at a temperature varying from 0 to 3°C and at a R.H. between 85‐90%. During the storage a part of the control berries was irradiated at different times to find out differences in irradiation response at successive stages of ripeness in storage conditions. The effects of irradiation on the pectic substances, pectinmethylesterase activity and anthocyanin content were investigated. In addition, changes in softening and extent of fungal growth were followed. A different response of strawberries irradiated at two different stages of ripeness was found. The different ripeness in storage conditions also influences the radiation response of the strawberries. The possible practical applications of these findings are discussed.