| The red jujube were selected as raw material,jujube brandy were made by fermentation,distillation,storage and aging.It mostly was produced in the family workshop without any blending and produces the unique flavor in the manufacturing process.The flavor and product quality control have been affected because of its characteristic aroma components is not clear.In this study,jujube brandy was used as the research object.Firstly,a method for determining the aroma components of jujube brandy was established.Then,the characteristic aroma components in jujube brandy were studied by the method of sensomics approach.Finally,the effects of different toasting degree of oak chips on the aroma of jujube brandy were studied.The main tests and results are as follows:1.The extraction method of aroma components in jujube brandy was studied.A method for the aroma components of jujube is established.Firstly,the extracting effects of three extraction solvents(dichloromethane,pentane and diethyl ether)on the extraction of aroma components were compared.And dichloromethane was selected as the best extraction solvent.Secondly the effect of HS-SPME fiber on the extraction of aroma substances in jujube brandy was studied,the best extraction fiber was CAR/DVB/PDMS.Finally,the extraction conditions were optimized using single factor and orthogonal experiments.Experimental results showed that the optimal HS-SPME extraction time and temperature were 40 min and 50 ℃,10% alcohol content in headspace glass vial with addition of 1.0 g NaCl,and the desorption time was 6 min.As a result,59 aroma compounds were extracted out of the tested liquor sample,including 34 esters(85.47%),7 alcohols(3.67%),4 acids(4.61%),6 ketones(4.51%),8 others(1.74%).2.The characteristic aroma components in jujube brandy were studied by the method of sensomics approach.Firstly,63 aroma compounds were identified in jujube brandy by gas chromatography-olfactometry(GC-O)and gas chromatography-mass spectrometry(GC-MS).Ethyl 3-phenylpropionate,ethyl butyrate,ethyl 2-methylbutanoate were identified to have the higher dilution factor and osme value,and they had a certain contribution to the overall aroma of the liquor.Secondly,34 aroma compounds with osme values of ≥2.00 were quantified and odor activity value(OAV)analysis.The results showed that ethyl ethyl 2-methylbutanoate had a higher OAV,followed by ethyl butyrate,ethyl valerate,ethyl laurate,and ethyl hexanoate.Finally,21 kinds of aroma components with OAV≥1 were subjected to recombination experiments.And aroma omission/additive experiments were performed on some special aroma components.Recombinant experiments successfully simulated the studied jujube brandy,and ethyl acetoate was determined as a characteristic of jujube brandy by aroma omission experiment,followed by ethyl 2-methylbutanoate,3-methylbutanol,butanol,pentanoic acid.3.The effects of toasting degree of oak chips on jujube brandy aging was study.Feshly-brewed jujube brandy was aged with differently baked oak chips to speed up physical and chemical reactions during storage and to monitor changes in flavor during aging.The results show that more aroma components were obtained by the moderate baking oak in the aging period.As for the varieties and contents of aroma components during aging,the effect of moderate baking oak is better than other two baking oak chips.Therefore,the study of the characteristic flavor substances in jujube brandy can provide reference for industrial production of jujube brandy. |
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