Analysis Of Flavor Components And Stability Of Jujube Brandy

Jujube brandy is a kind of liquor which is produced by the process of enzymatic hydrolysis,fermentation,distillation and aging.At present,the research on jujube brandy is mainly focused on the component analysis and methanol content control,but it has not been reported on the flavor components and stability systematically.Therefore,it is important to analyze and study it,which can provide a basis for the production and quality control of jujube brandy.The paper taking jujube brandy as the research object,using the meteorological chromatography,mass spectrometry,sniffing,ultraviolet and infrared detection methods,studied the flavor composition and characteristics of aroma substances and stability.The specific research contents and results as follows:1.Analysis of flavor componentsThe flavor components of jujube brandy was isolated and identified by direct injection,using gas chromatography,gas chromatography-mass spectrometry combined with olfactory.The qualitative analysis of the flavor components were verified respectively by mass spectrum,retention index and olfactometry.The quantitive analysis results were obtained by the analysis of n-amyl acetate,2-ethylbutyric acid and tert-pentyl alcohol as internal standard.A total of 56 compounds were isolated,of which the structure of 52was identified,accounting for 99.72%of the total flavor components in jujube brandy.Evaluation of OAV and aroma intensity values indicated that ethyl acetate,butanoic acid ethyl ester,pentanoic acid ethyl ester,hexanoic acid ethyl ester,octanoic acid ethyl ester,acetic acid,butanoic acid,pentanoicacid and hexanoic acid were the main flavor components.2-phenylethyl acetate and benzenepropanoic acid ethyl ester also added certain jujube aroma in jujube brandy.2.Study on color stabilityIt studied the color stability of alcohol degrees,temperature,light,pH and met-al ion by ultraviolet spectrometer,which showed that reduced alcohol content is favorable to the improvement of its color stability,Fe³⁺,Al³⁺,Cu²⁺and the increase of the pH value,the maximum absorption wavelength of jujube brandy chromophore will be shifted to long wavelength direction in a certain degree,the preservation of the light,heating jujube brandy to make the absorbance value has increased;natural light absorbance value decreased slightly.The pigment is preliminarily speculated to be an aromatic species by comparison with relevant literatures.3.Analyzed the cause of turbidity and established a clarification methodThrough the analysis of different degrees of jujube brandy,it was found that the wine had appeared different degree of losing light and turbidity during the decrease or increase of alcohol degree.It can be seen from the infrared spectrum and chemical method that the turbidity of 20%vol jujube brandy was mainly polyphenols and protein association,with a small amount of fatty acid esters,the turbidity of 72%vol jujube brandy was mainly water-soluble polyphenols and saccharides.The single factor and response surface methodology were performed on the wine by adding different clarifiers,which showed that the optimal clarifier of 20%vol jujube brandy was chitosan gelatin composite clarifying agent,the dosage of chitosan 0.066g/L and gelatin 0.64 g/L,the maximum transmission rate 99.825%,72%vol jujube brandy should choose diatomite as clarifier,its dosage was 0.12 g/L,the maximum transmission rate was 99.972%.