INFLUENCE OF HARVEST DATE ON THE SYNTHESIS OF VOLATILE COMPOUNDS IN STORED FRUITS OF APPLES ‘GOLDEN DELICIOUS’ AND ‘RED DELICIOUS’

Abstract

The effect of harvest date on the production of volatile compounds in fruits two apple (Malus domestica Borkh.) varieties, ‘Golden Delicious’ and ‘Red Delicious’, was studied. ‘Golden Delicious’ fruits were harvested before the beginning of climacteric peak (internal ethylene concentration, IEC = 0.003 ppm) and at the beginning of climacteric peak (IEC = 0.9 ppm), at 157 and 176 d after full bloom (dafb ), respectively. ‘Red Delicious’ fruits were harvested at the beginning of climacteric peak (IEC = 0.3ppm) and at climacteric peak (IEC = 17 ppm), at 176 and 191 dafb , respectively. The fruits of both varieties were stored at 0 °C during 150 d, and the aroma profile was analyzed every 30 d. During most of the storge time ‘Golden Delicious’ fruits harvested at 157 dafb showed a higher content (P < 0.05) of aldehydes hexenal, hexanal and hexanol, all of these flavor compounds characteristic of unripe apple during most of the storage time, as compared to the fruits harvested at the beginning of climacteric peak (176 dafb ). The later harvest produced the greatest concentration (P < 0.05) of the alcohols 1-butanol and 2-methyl-1-butanol, and of the ester butyl acetate, characteristic compounds of the sweet fruity flavor of a ripe apple. ‘Red Delicious’ fruits harvested at 176 dafb showed a considerably higher amount of cis-3-hexanal, butyl acetate and 2-methyl butyl acetate, important constituents of flavor, than the those harvested at 190 dafb . These results show the relationship between apple maturity and the production of flavor volatile compounds during storage, evidencing that harvesting too early or late may affect negatively the production of these compounds and the flavor development during storage.