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Ground fennel seeds were extracted with supercritical carbon dioxide. Small-scale subsequent extractions of the same sample showed that the composition of volatile compounds was changed with the extension of extraction time and only principal volatile components (limonene, fenchone, methylchavicol, and anethole) were present in the last-extracted sample. Fennel oil was successfully fractionated into the essential oil rich and fatty oil rich products in pilot-scale apparatus using two separators in series. Designed experiments were carried out to map the effects of pressure and temperature in the first separator on the yields and compositions of the products. The minimum level of the total undesired components in both essential oil rich and fatty oil rich products appeared at a pressure of 80-84 bar and a temperature of 31-35 degrees C in the first separator. Supercritical CO(2) extraction of fennel seeds resulted in higher yield (10.0%) than steam distillation (3.0%), almost the same yield as hexane extraction (10.6%), and lower yield than alcohol extraction (15.4%). Analysis of the volatile compounds revealed the significant difference of the composition in distilled oil and oleoresins prepared by CO(2) and solvent extractions. Sensory evaluation showed that the CO(2) extraction product and distilled oil were more intense in odor and taste than alcohol and hexane extracts.

Biogenic amines in grapes, aszu-grapes, wines, and aszu-wines of the Tokaj region of Hungary were separated, identified, and quantified by HPLC. The biogenic amine content of the Tokaj wines was well below the suggested limits for any of the biogenic amines. Histamine contents were especially low in all the samples investigated. The composition and concentration of the biogenic amines (polyamines) in the grape berries were altered remarkably by the Botrytis cinerea, and this resulted in a great change of the amine concentration in the aszu-wines compared to the wines. The composition and concentration of biogenic amines might provide useful information on the vintage and can support the authentication of the Tokaj aszu-wines.

SummaryThe biologically active amines agmatine, cadaverine, histamine, phenethylamine, putrescine, spermidine, and tyramine have been determined in different varieties of grape, aszu grape, wine and aszu wine from the Tokaj region of Hungary. Ion pairs formed between the amines and octanesulphonic acid were separated by liquid chromatography on a #Bondapak C18 reversed-phase column, and spectrofluorimetric detection was performed after post-column derivatization with o-phthalaldehyde and 2-mercaptoethanol. The method was linear for the amines between 0.1 and 10 mg L -1, and for spermidine between 1 and 30 mg L 1. Comparison of the results revealed that the qualitative and quantitative content of biologically active amines was mostly determined by the vintage of the wine and the technology used for wine-making. The biogenic amine content of Tokaj wines is well below suggested limits for any of the amines, showing that the winemaking technology of the Tokaj region is of high quality. The levels of biologically active amines (identified and quantified by HPLC) in grapes, wines and aszu wines can provide useful information about the weather, growth of Botrytis cinerea in Tokaj, and aspects of the methods used for wine-making.