Study On The Key Aroma Compounds Of Millet Wine

Huangjiu is the oldest alcoholic beverage in China,Because of its complex aroma,Huangjiu is very popular with consumers.Millet is the main raw material of millet wine,which mainly produced in northern China.Due to raw materials and processes produced a unique flavor.However,the current research on the flavor of millet wine mainly focuses on the qualitative and quantitative of volatile compounds,the key flavor compounds of millet and the influence of the processes on the flavor of millet wine is still unclear,which restricted the further development and quality improvement of millet wine.This study used molecular sensory science to confirm the key flavor compounds in millet wine,and explored the influence of processes on flavor compounds.The main research conclusions are as follows:(1)Comprehensive two-dimensional gas chromatography-time of flight mass spectrometry was used to analyze the volatile compounds in millet wine.The effects of headspace solid phase microextraction and solid phase extraction combined with GC×GC-TOFMS to analyze volatile compounds were compared.A total of 460 compounds were identified in millet wine,the esters,furans,pyrans,sulfur-containing compounds and nitrogen-containing compounds were detailed analyzed.(2)The sensory characteristics of three typical millet wines were described by quantitative descriptive analysis.In the sensory description of the three type millet wines,there are significant differences in the aroma intensity of caramel,burnt,fruity,smoky,nutty,and flowery.A total of 73 aroma compounds were qualitatively identified by Gas Chromatography-Olfactometry combined with GC×GC-TOFMS.Quantified 70 aroma compounds,and analyzed the contribution of aroma compounds in millet wine by Odor Activity Value.A total of 46 aroma compounds such as furaneol,phenol,ethyl butyrate,ethyl valerate,ethyl isovalerate ester,methyl cyclopentenolone,ethyl octanoate,ethyl caproate contribute to the aroma of millet wine(OAV>1).The aroma recombination model had a high similarity with the sample wine.Furthermore,the aroma omission experiment confirmed furaneol,phenol,ethyl butyrate,ethyl valerate,ethyl isovalerate,methyl cyclopentenolone,p-cresol,ethyl acetate,2-acetylpyridine,sotolon made important contributions to the overall aroma of millet wine.(3)The ?-? model method was used to study the perceptual interaction among 10 compounds corresponding to smoky,nutty,and caramel aroma.Among the 45 binary mixtures,8 groups had synergistic effects,22 groups had partial additive effects,11 groups had compromise effects,and 4 groups had masking effects.Similar chemical structures and aroma descriptions in this study were more likely to have synergistic effects.(4)Multivariate statistical analysis method divided Shandong,Liaoning and Shanxi,Shaanxi millet wine into two groups.Maltol,methyl cyclopentenolone,ethyl cyclopentenolone,phenol,3-methyl-2-5(H)-furanone,p-cresol,furfuryl alcohol,furaneol,?-butyrolactone were characteristic compounds caused the differences between the two groups.(5)The influence of the fermentation processes on the flavor of millet wine was studied through sensory combined with quantitative analysis.Millet boiling stage produced a large amount of furans,pyrans,ketones,phenols,and nitrogen-containing compounds in the millet wine,which resulted in the flavor of caramel,burnt,nutty,and smoky aroma in millet rice wine;The fermentation stage produces a large amount of alcohols and esters;During the sterilization stage,the content of esters and aldehydes were reduced due to continuous heating;During the aging stage,the content of esters and aldehydes continued to rise,while the content of ketones,nitrogen-containing compounds,and sulfur-containing compounds continued to decrease.