Study On Volatile Compounds From Currants

Currant was used as materials in this study, which were collected from the garden of Northeast Agricultural University. After studied the factors that affected the separation of volatile compounds from blackcurrant berries by Solid-PhaseMicroextraction (SPME), influence of stage of ripeness on the changes of volatile compounds in blackcurrant fuits of the varieties Brodtrop and the differences of volatile compounds in blackcurrant leaves ,buds and seeds and the volatile composition and content differ from various currants were analyed by using gas chromatography/mass spectrometry (GC/MS). The transformation of volatile compounds during blackcurrant juice processing and the volatile constituent of blackcurrant concentrated juice and fermented juice Finally was studied. The main results were as follows:The optimum results were headspace extraction at 55℃for 20 min with 1g of the sample.The order that effected on volatile extraction: temperature>time>sample quantity.A total of 49 component identified at the green stage and represented 86.40% of total peak area.At the red and black stage, 60 and 52 components were detected from Brodtrop,which represented 93.06% and 94.92%of total peak area. The main volatile components of Brodtrop were terpenes,esters,alcohols,ketone and aldehyde.Terpenes were the major volatile compounds from Brodtrop during ripening and the relative amounts of other volatile compounds were lower.The relative amounts of terpenes and esters tended to slightly increase. The content of alcohols,ketone and aldehyde increased at first but decteasde later.The content of acids,ethers and other compounds was very low during ripening,and the change of them has no remarkable regularity.Terpenes were the predominant types of volatile compounds identified from blackcurrant leaves,buds and seeds.A total of 43 volatiles were identified from leaves,which represented 98.78% of total peak area.The numerous compounds found were trans-.beta.-Ocimene,cis-.beta.-Ocimene, Caryophyllene,beta.-Phellandrene,gamma.-Elemene,delta.(Sup3)-Carene.A total of 57 volatiles were identified from buds,which represented 95.58% of total peak area.The numerous compounds found were Caryophyllene,beta.-Phellandrene,delta.(Sup3)-Carene, alpha.-Caryophyllene, Bornyl acetate ,Terpinolene. A total of 43 volatiles were identified from seeds,which represented 85.21% of total peak area.The numerous compounds found were Caryophyllene,alpha.-Pinene, (+)-4-Carene,delta.(Sup3)-Carene ,beta.-Pinene.The essential oil of blackcurrant leaves and buds could us as flavor enhancer in blackcurrant products and extend the deep processing of blackcurrant .A total of 21 volatiles were identified from redcurrant,which represented 59.98%of total peak area.The numerous compounds found in redcurrant were Caryophyllene, Bornyl acetate, alpha.-Caryophyllene, Benzyl Benzoate. A total of 33 volatiles were identified from whitecurrant,which represented 70.76% of total peak area.The numerous compounds found in whitecurrant were Caryophyllene, Bornyl acetate, alpha.-Caryophyllene, Benzyl Benzoate.During blackcurrant juice processing, 43,26,17 and 23 components were detected from crushing,pressing,filtration and pasteurization,which represented 71.85%,44.80%,39.36% and 60.00%of total peak area. The major groups of volatile compounds were alcohols, esters, terpenes and alkanes. The relative amounts of alcohols and alkanes tended to slightly increase, whereas The content of esters and terpenes decteased. A total of 32 volatiles were identified from marc of blackcurrant,which represented 65.55% of total peak area.The numerous compounds found were acetic acid ,Caryophyllene, Bornyl acetate, delta (Sup3)-Carene .A total of 15 and 27 volatiles were identified from concentrated blackcurrant juice and fermented blackcurrant juice,which represented 43.32%,80.45%of total peak area.The numerous compounds found in concentrated blackcurrant juice were Acetic acid, Hexadecane, 2,6,10,14-Tetramethylhexadecane, Benzyl Benzoate. The numerous compounds found in fermented blackcurrant juice were Ethyl alcohol, Isopentyl alcohol, Ethyl Acetate, Ethyl hexadecanoate.