EFFECT OF MATURITY AND STORAGE ON QUALITY AND VOLATILE PRODUCTION OF JONAGOLD APPLES

'Jonagold' apples (Malus domestica Borkh.) harvested 3 times at bi-wee kly intervals starting approximately two weeks prior to commercial har vest were stored at 0 degrees C in air and controlled atmosphere (CA, 1.5% O-2 + 1.5% CO2 for six months. Starch index (SI) increased from 2 .1 to 8.4 during the harvest period. Early harvests and CA significant ly (P less than or equal to 0.05) reduced the loss of acidity and firm ness in stored apples but did not influence total soluble solids conte nt. CA decreased the volatile production testers, alcohols, and hydroc arbons) by half. The last harvest (SI = 8.4) provided an increase of 1 4% in volatiles compared to the first date (SI = 21). These increases were mostly due to straight C3-C6 chain acetates and alcohols, and the hydrocarbon alpha-farnesene. Variation in background skin colour with in the same harvest period had a negligible effect on volatile pattern s. Harvest at starch index values of 6.5-8.5 allowed higher concentrat ion of odour-active compounds while retaining acceptable levels of aci dity and firmness.