INTEGRATED MANAGEMENT OF POSTHARVEST FRUIT QUALITY

Granny Smith apples, not treated with DPA, were subjected to initial low oxygen stress (ILOS) conditions and stored at 0 °C under CA conditions. CA storage was followed by 4 weeks under RA conditions. No superficial scald developed during a storage period of 18 weeks. The incidence of superficial scald on untreated Topred apples, subjected to ILOS and ULO and stored for 32 weeks, was low. Superficial scald can therefore be controlled without the application of DPA. Granny Smith apples, heated to 36 °C for 4 days and stored at -0.5 °C for 12 weeks did not develop superficial scald. DPA applied to Granny Smith by means of thermofogging controlled superficial scald successfully. The frequency and distribution patterns of fungi causing postharvest decay in the orchard, packing and storage environments were not random but followed definite trends. Differences were recorded between samples collected in the interrow and those collected under the tree canopy, as well as between insect species sampled. Penicillium and Mucor spp. commonly occurred on fruit surfaces and equipment in the packhouse. Disinfection of water reduced the number of propagules on fruit surfaces but recontamination resulted in high counts on surfaces of packed fruit. Control of physiological and microbiological disorders should be regarded as an integrated process which starts in the orchard and is concluded in the packhouse. The approach should therefore be holistic, taking into account all factors affecting fruit quality in order to develop an integrated system of postharvest quality management.