Title: Influence of harvest time on quality of ‘Valencia’ oranges and juice, 2nd season Authors
|Paula, Bruno -|
|Gloria, Beatriz -|
Submitted to: Florida State Horticultural Society Meeting
Publication Type: Proceedings
Publication Acceptance Date: August 1, 2013
Publication Date: N/A
Interpretive Summary: The quality of orange juice from oranges harvested over the four-month harvest window can vary and the flavor, nutritional and phytochemical component levels can change over this harvest window. This study was a follow-up to a previous study to determine the changes in these important components over the harvest season for ‘Valencia’ oranges, the premier juice orange in Florida. Results showed that the latter part of the season was optimal for flavor and phytonutrients, but the earlier season was optimal for vitamin C levels.
Technical Abstract: ‘Valencia’ oranges were harvested from February to May, 2012 in the Indian River area of Florida, and the effects 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. Not surprisingly, peel color became less green and more orange over the season. Juice content in fruit declined as the season progressed, as was found in the previous study. For sugars, the solids/acid ratio increased over the season, as expected and as was found in the previous study. Titratable acidity, citric acid and total ascorbic acid declined over the season as in the previous study and the phenolic compounds generally increased, whereas they had fluctuated in the previous study. Limonoids generally increased as the season progressed except for the bitter compounds, limonin and nomilin, which increased and then decreased in the last month. In the previous study these compounds had continued to decrease until the end of the season. Alkaloids increased throughout the season. Hydroxycinnamates all decreased over the season. For volatiles, considered important for orange juice flavor, terpene, aldehyde, ester and alcohol volatiles increased steadily or in the last months of the season except for 2-carene and a-terpinene, in agreement with the previous study.