Vol. 119 (2006): Proceedings of the Florida State Horticultural Society
Citrus

Impact of late harvest on citrus crop losses and juice quality

L. Gene Albrigo
University of Florida

Published 2006-12-01

Keywords

  • preharvest fruit drop,
  • return crop,
  • juice content,
  • Brix,
  • acidity

Abstract

Following the freezes of the 1980s and the 2004 hurricanes, the number of processing plants and packinghouses decreased as a result of reduced availability of fruit, and structural damage to some packinghouses. During the same period, the shift from FCOJ (Frozen Concentrated Orange Juice) to NFC (Not from Concentrate) required increased cold storage capacity as more juice was being stored as single strength. Processors preferred for growers to delay harvest and hold fruit on the tree rather than having to increase processed product storage capacity. Growers have been concerned about their fruit losses from preharvest drop and return crop, reduced juice content and higher sugar to acid ratios above the preferred range for best consumer acceptance of NFC. Previous studies and data from the Florida Agricultural Statistical Service (FASS) confirmed that preharvest drop increased about 3% loss per month of delay in harvest, and yield in the following year decreased in response to late harvest. These combined losses can be as much as 20% but more typically are in the 10 to 15% range. Juice content and soluble solids per box did not decrease through February for early-midseason oranges, or through June for late harvest cultivars. The average brix/acid ratio did increase to the upper acceptable level (19) by February in early-mids and by June in late season cultivars. Many citrus blocks are out of the acceptable ratio range by these dates. Selecting blocks with smaller crops for late harvest to minimize reduced return crop effects and choosing high acid fruit for late harvest in order to provide acceptable ratio fruit for NFC late in each harvest period may be desirable. In some years, preharvest drop rates were much higher than in other years. The reasons for this should be examined.