SOURCES OF VARIATION IN FRUIT QUALITY OF `BRAEBURN' APPLE AT HARVEST AND AFTER STORAGE.

Abstract

Export-packed fruit of `Braeburn' apple ware collected on three dates corresponding to the early, mid and late periods of commercial harvest. Fruit were segregated into categories determined by background color, combined with percent fruit surface area with red blush of <40%, 40-70% and >70%. A separate category comprised fruit which showed marginal sunburn discolouration. Fruit were assessed at harvest and after 16 weeks air storage at O°C. Quality and maturity indices which were affected by harvest date included starch pattern index, flesh firmness and soluble solids concentration (SSC). However differences due to harvest data were not evident after storage. Fruit with more yellow background color or marginal sunburn were distinguished by advanced starch hydrolysis, higher internal ethylene concentration and higher SSC at harvest. After storage these fruit had yellowest background color, softer flesh and highest SSC. Fruit with green-yellow background color and >70% blush showed similar but less pronounced trends. Organoleptic assessment after storage showed a higher frequency of inferior texture and juiciness associated with categories of fruit with indices indicating advanced maturity at harvest and following storage.