Extractor Pressure and Extractor Types

Dougherty et al. (36) also showed that there was an average 65% increase (range, 17-167%) in limonin content of juice obtained using a soft versus hard squeeze using an FMC Corp. (Lakeland, Fla.) extractor. This was based on values obtained from five batches of Marsh grapefruit harvested between September 12-17, 1974, and processed at both soft and hard squeeze settings. Similar results were obtained, but not presented, for the Duncan cultivar. In the 1975-1976 season, the same authors used FMC Corp. and Automatic Machinery Corp. (Winter Haven, Fla.) extractors to produce juice from three batches with each machine of Florida grapefruit at about monthly intervals beginning in October for both Marsh and Duncan cultivars. The data again showed more limonin extracted with the hard squeeze than with the soft squeeze and for both extractor types. In addition, one extractor produced an overall average of 34% (ranging from 6 to 63%) more limonin than did the other extractor for the same batches of fruit.

These results are not surprising as limonin is most prevalent in the seeds at levels in excess of 0.5% wet weight (37). Limonoic A-ring lactone, the nonbitter precursor to limonin occurs at highest concentrations in the fruit core, followed by the segment membranes, and peel (39). Any process that tends to crack the seeds or cause more peel and pulp constituents to be incorporated into the juice product will result in higher limonin values. Grapefruit core and segment membranes contain 500 to 1500 ¿ug/g limonin; and the peel, 12 to 234 ¡ug/g (39).

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Sleeping Sanctuary

Salvation For The Sleep Deprived The Ultimate Guide To Sleeping, Napping, Resting And  Restoring Your Energy. Of the many things that we do just instinctively and do not give much  of a thought to, sleep is probably the most prominent one. Most of us sleep only because we have to. We sleep because we cannot stay awake all 24 hours in the day.

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