Effect of juice extractor settings on Hamlin orange juice cloud stability

Three different juice extractor settings were used to obtain juice from Ham lin oranges. Cloud in Soft and Medium extracted juice had nearly identical A,, values. The A(660) of the Hard extracted juice was greater than the oth ers. At 30C A(660) for both the Soft and Medium juice increased slightly ov er time while the Hard juice A, decreased. The cloud in all three raw juice s showed a decrease in A(660) at 4C. Specific activity of pectinmethylester ase in the raw juices was very similar, but was higher in protein extracts from the Hard juice than from Medium or Soft juices. Addition of protein ex tracts from each juice, to reconstituted FCOJ, demonstrated that cloud loss in these treatments was dependent on extraction pressure. At 30C PME in th e extract from the Soft extracted juice destabilized the cloud most rapidly . Cloud loss also was dependent on the amount of PME activity added.