ARS | Publication request: Effect of early detection greening on juice flavor and chemistry

Submitted to: Florida State Horticultural Society Meeting
Publication Type: Abstract
Publication Acceptance Date: April 5, 2008
Publication Date: April 23, 2008
Citation: Plotto, A., Baldwin, E., Mccollum, G., Irey, M. 2008. Effect of early detection of greening on juice flavor and chemistry. Florida State Horticultural Society Meeting. Paper No. HP2.

Technical Abstract: When Huanglongbing (HLB) was first discovered in Florida, trees with early symptoms of disease were harvested to determine whether there was any flavor difference between juice made from infected trees but with asymptomatic fruit, and fruit harvested from healthy trees. It is of interest to the processing industry to determine what affect fruit from trees of various stages of infection would have on processed orange juice quality. Valencia oranges were harvested in 2006 from HLB-positive trees in the early stages of disease development (HLB fruit), and compared to fruit from healthy trees. A consumer panel did not perceive differences for juice taste or smell between healthy and HLB fruit in a triangle test. An experienced panel, however, did perceive that juice from HLB fruit was sweeter than juice from non-HLB fruit. Further tests were performed by using the "difference-from-control" test with filtered or unfiltered juice, to determine the effect of pulp on difference perception. When juice was filtered, panelists could perceive a difference by smell and by taste; when juice was served unfiltered they could only perceive a difference by taste. One of the descriptors that came up frequently for the HLB filtered juice for taste difference was again "sweeter". Chemical analyses showed that the juice from HLB fruit was higher in Brix/acid ratio than from juice from non-HLB fruit which is in agreement with the "sweeter" perception. No consistent differences in aroma volatiles between juice of HLB and non-HLB fruit were observed.