| Abstract
| - Linalool concentrations were determined in juice from three groups of 60 Valencia oranges usingpentane:ether extraction and high-resolution capillary GC. The outer peel (flavedo) was removedfrom one group. The other two groups retained their peel intact. Juice was extricated from the halvedfruits of the flavedo-less group and from one of the peel-intact groups using a hand reamer. A peel-cutting/macerating juice extractor was used for the other peel-intact group. Linalool concentrationswere 0.004 mg/L in peeled fruit juice and 0.020 and 0.106 mg/L for hand-reamed and mechanicallyextracted peel-intact juice, respectively. Juice from peeled fruit contained significantly (P< 0.05)less linalool than peel-intact juice. Approximately 80% of the total juice linalool content was associatedwith peel using reamer design, and 96% was associated with peel-cutting/macerating design. Linaloolincreased with increasing peel oil levels; however, the increases were not proportionate. Since allcommercial juices are mechanically extracted, the vast majority of linalool in commercial orange juiceoriginates from the peel and not from the juice vesicle cytoplasm. Juice from peel-macerated,mechanically extracted fruit increased from 0.106 to 0.134 mg/kg after thermal processing, whereasjuice from reamer extraction was essentially unchanged. Keywords: Pasteurization; flavor changes; aroma impact; citrus; flavedo; orange peel
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