Study On Aroma Compounds Of Zhizhonghe Wujiapi Medicinal Liquor

Zhizhonghe wujiapi medicinal liquor(WJP liquor)is produced in Jiande district of Hangzhou city,Zhejiang province.It uses its self-made liquor as the base liquor,with addition of more than ten precious Chinese medicinal herbs,including Acanthopanacis Cortex,Fructus Gardeniae,Radix Aucklandiae,Cinnamomi Cortex,Lycii Fructus,etc.,as well as the spring water taken from Qiandao Lake in Zhejiang province,which were thoroughly mixed and followed by a unique processing called of " fermentation by two times and infusion by four times ".As a result,WJP liquor not only has a rich and pleasant aroma and a sweet and mellow taste,but also health benefiting functionalities such as promoting blood circulation,relieving fatigue,and enhancing immunity.However,no systematic research has been done on the volatile aroma components of the WJP liquor,not alone to say the studies on the flavor profiles between the WJP liquor and other liquors,which has significantly influenced the quality consistency and improvement of the WJP liquor.In this study,WJP liquor,a special health benefiting medicinal liquor produced in China,was investigated for its volatile aroma components by different detection technologies GC-MS and GC-O with aid of four different extraction methods,including HS-SPME,SDE,SAFE and SBSE.With aid of the aromatic extract dilution analysis method(AEDA)combined with aroma vitality value(OAV)calculation,using 43 kinds of OAV ≥ 1 aroma substance recombination model successfully blended with the original WJP liquor sample with similar aromas.Furthermore,29 key aroma substances that make up the aroma characteristics of WJP liquor were further identified through the aroma omission test,for which the main research results and conclusions are listed as follows:(1)In regards of the complex aroma composition of WJP liquor,this study at first investigated four different extraction methods suitable for the extraction of aroma components of WJP liquor,including headspace solid phase microextraction,simultnaeous distillation extraction,solvent-assisted flavor eavporation,and stir bar adosrption extraction.And at the same time,through gas chromatography-mass spectrometry(GC-MS)analyzes the extract obtained after separation and concentration.In terms of the separation and concentration of the aroma compounds.The results showed that 173 volatile compounds(including 34 esters,17 acids,15 alcohols,25 aldehydes,9 ketones,12 heterocycles,42 terpenes,8 hydrocarbons,6 phenols and 5 others)were separated and identified from the WJP liquor by the four extraction methods.Regarding each extraction method,99,67,108 and 51 volatile compounds were respectively identified from the HS-SPME,SDE,SAFE and SBSE extracts.Among them,13 volatiles were found in all four extracts.(2)The aroma-active compounds of the WJP liquor that were extracted by the SDE and SAFE methods were further analyzed by gas chromatography-olfactory sniffing method(GC-O)with aid of the AEDA method.Among these 72 aroma active substances,in addition to esters,alcohols,acids,aldehydes,ketones and and other aroma substances,which are common aroma compounds in other Chinese liquors,have been identified.Besides,p-anisaldehyde(anise odor),cinnamaldehyde(cinnamon odor),camphor(camphor odor),eugenol(clove odor),p-allylphenol(herb odor),isobutanol(clove odor),4-allylanisole(anise odor),anethole(anise odor)that exhibited high aroma dilution factor(FD value)were identifed.These aroma compounds have presented a special plant aroma and medicinal odor,which make an important contribution to the formation of the unique aroma characteristics of the WJP liquor.(3)Furthermore,66 volatile aroma compounds with their FD value ≥ 9 in the extracts of WJP liquor were comprehensively analyzed by using a combination of multiple quantitative methods.Those results showed that the identified esters,alcohols and aldehydes are the main aroma components of the WJP liquor,among which ethyl lactate,isoamyl alcohol,acetal and propanol are the most important volatile aroma compounds in the WJP liquor(content>100mg/L).According to the determined OAV values,the top six aroma compounds with the highest OAV value were anethole(OAV = 1073),p-anisaldehyde(OAV = 409),4-terpenol(OAV = 386),ethyl octanoate(OAV = 226),4-allyl anisole(OAV = 198)and acetal(OAV =103).(4)Moreover,the aroma reconstitution and aroma omission models of the important volatile aroma compounds with OAV value ≥ 1 were prepared under the simulated conditions of the original WJP liquor and compared with the genuine WJP liquor.The former was composed of 43 volatile aroma-impact compounds with their OAV value ≥ 1.The study found that the reconstituted sample and the WJP liquor have exhibited high degree of similarities in their aroma profiles in terms of the spicy,fruity,floral,woody,and alcohol aromas,except.The medicinal,fatty and sweet aromas with slightly difference,which confirmed the validity of the preliminary qualitative and quantitative results and the GC-O/AEDA analysis.The aroma omission test further verified 29 volatile aroma compounds,including ethyl ethyl octanoate,3-hydroxy-2-butanone,2-nonone,ethyl hexanoate,vanillic acid,ethyl2-methylpropionate,d-limonene,isoamyl acetate,p-anisaldehyde,3-phenylpropanol,Isobutyl acetate,butanoic acid,4-terpenol,p-allylphenol and,etc.,are the key characteristic aroma compounds for the construction of the major aroma profile of the WJP liquor.It also play an important role in the formation of an overall aroma of the WJP liquor,and they are the key characteristic flavor components of the WJP liquor.