| Abstract
| - Juice was extracted from Valencia oranges using three different extractor settings. Differential juicecloud stability was observed. Soft-extracted juice was the most stable, and hard-extracted juice wasthe least stable. The medium-extracted juice had intermediate cloud stability. Yearly (1997 versus1998) differences were observed, but the relationship among the juices did not change. Addition ofprotein extracts, obtained from each juice, to pasteurized juice also resulted in differential cloudstability. Using pectinmethylesterase (PME) activity estimated at pH 4.5, the effects of the proteinextract mirrored results from raw juice. Estimating PME activity at pH 7.5 produced contradictoryresults, indicating that predicting consequences of PME activity estimated at pH 7.5 is unreliable. Keywords: Citrus; juice processing; orange juice; juice cloud; cloud stability
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