Project Number: 6621-41440-003-11
Project Type: Trust

Start Date: Mar 06, 2009
End Date: Mar 06, 2010

Objective:
Quantify sensory flavor changes and chemical differences due to Huanglongbing (HLB) disease, and identity off-flavored components as well as determine thresholds of off-flavors in normal juice. Investigate impact of the disease on juice cloud precipitation and secondary metabolites, pectin structure and pectin degrading enzymes. Look at differences in metabolites in healthy versus diseased leaves.

Approach:
Obtain fruit from diseased and healthy trees and use to run difference-from-control, triangle and trained sensory panels. Analyze juice for volatiles, sugars, acids and secondary metabolites using gas chromatography-mass spectroscopy (GC-MS), GC-olfactometry (GC-O), high performance liquid chromatography (HPLC) w/wo MS to quantify sugars, acids and secondary metabolites as well as pectin. Perform enzyme assays on pectin in juice cloud to determine pectinmethylesterase (PME) activity.