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The total carotenoid concentration of the seeds of Momordica charantia rose about 100-fold from the immature to the ripe stage. The massive increase was almost exclusively attributable to lycopene, which accounted for 96% of the carotenoids of the ripe seeds. The carotenoid pattern of the seed was found to be drastically different from that of the pericarp. The seed, which contained fewer carotenoids, had a total concentration 12 times greater than that Ripe cherry tomatoes, Lycopersicon esculentum var. Cerasiforme (Dun.) A. Gray, were purchased from a local fruit market. The cherry variety was used because the seeds were easier to separate. The seeds from 900 g of fruits were separated from the pericarp and washed with water on a sieve to remove juice and residual pulp. The water was drained and the seeds were air dried on the sieve for a couple of hours. Four 30-g samples were taken and analyzed separately.In addition to the authentic carotenoids used for comparison in the preceding study, lycoxanthin and rubixanthin were extracted and purified from Solanum dulcamara and rose hips, respectively.Extraction and Separation of Carotenoids. The carotenoids of the seeds of both fruits were extracted and saponified in the same manner described for the pericarp (17). The saponified pigments from the ripe and partly ripe Momordica samples were separated initially on a column of alumina (activity grade III), using 1 to 5% (v/v) ethyl ether in petroleum ether as solvent. Fraction 4 was rechromatographed on a MgO-HyfloSupercel (1:2) column developed with 25% (v/v) acetone in petroleum ether, resulting in the formation of five bands (fractions 4-a to 4-e). If necessary, these bands could be purified on a silica gel plate (Quanta Gram TLC plates QIF, Quantum Industries, New Jersey) with 3%C (v/v) methanol in benzene as the developing solvent. The pigments extracted from the immature seeds separated into four bands on the alumina column. These fractions consisted of single carotenoids and thus needed no further separation. The topmost fraction of pigments from mature samples consisted of three components when rechromatographed on a silica gel plate developed with 3% (v/v) methanol in benzene. As in the previous study, the colorless eluate preceding the fluorescent phytofluene band was collected and examined for the presence of phytoene.The tomato seed carotenoids were fractionated as described for the whole fruit (15) except that lycopene was subsequently separated from the xanthophylls on an alumina column (activity grade III) developed with 1 to 5% (v/v)

Kona coffee cherries were demucilaged by either mechanical, enzymic or chemical methods, by the action of bacterial pure cultures, or by natural fermentation. Thirteen volatile components were detected by gas chromatography in all samples of green coffee tested, and these included methanethiol, acetaldehyde, dimethyl sulphide, propionaldehyde, acetone, isobutyraldehyde, butyraldehyde, ethanol, and isovaleraldehyde. Probably, methanol and/or methyl ethyl ketone also were present among the volatile components detected.The relative concentrations of several volatile components did not vary appreciably among the different lots of coffee demucilaged experimentally. However, acetaldehyde concentration increased as the duration of natural fermentation was prolonged, being markedly higher in grossly over-fermented (spoiled) coffee beans.All samples of coffee demucilaged experimentally had similar cup-testing quality (Kona grade No. l), indicating that none of the demucilaging methods enhanced or diminished coffee flavour or aroma. Over-fermented beans, however, were poor in cup-testing quality.