Published 2013-12-01
Keywords
- flavor,
- secondary metabolites,
- maturity,
- juice content
Abstract
‘Valencia’ oranges were harvested from February to May 2012 in the Indian River area of Florida, and the effect of harvest time on fruit and juice quality was investigated. This was a follow-up study to one done in 2007, where the fruit were harvested from southern Florida from February to June. Peel color became less green and more orange over the season, and juice content in fruit declined as the season progressed. For sugars, the solids/acid ratio increased over the season, and titratable acidity, citric acid, and total ascorbic acid declined. Phenolic compounds generally increased, whereas they had fluctuated in the previous study. Limonoids generally increased as the season progressed except for the bitter compound nomilin which remained steady. Alkaloids increased throughout the season. Hydroxycinnamates all decreased over the season. The polyamines spermidine and spermine increased, while spermidine remained constant. For volatiles, terpenes, aldehydes, esters, and ketones increased steadily or in the last months of the season. Alcohols (aliphatic and terpene alcohols) did not change over the harvest season. This study confirms changes of some chemicals over the harvest season, while other secondary metabolites are more dependent on the climatic conditions during fruit
formation and at harvest.