Effects Of Herbial Leaves On The Rice Wine Starter Microorganisms And Aroma Compounds Of Chi-flavour Liquor

Introducing herbal leaves into the starter substrate for wine fermentation is a historical technology but no reports could be found about its influence on microbial bioactivities.In this work,herbal leaves(Cinnamomum cassia,Folium Isatidis and Desmos chinensis)were added into fermentation substrate as auxiliary materials to investigate its effect on the starter's physicochemical and biological parameters.The optimal extraction method of Cassia leaf volatile oil was acetone extraction 6h under normal temperature.By integration of the peak areas,trans-cinnamaldehyde(30.02%),o-methoxycinnamaldehyde(43.96%),2H-1-benzopyran-2-one(10.82%)and n-hexadecanoic acid(2.49%)were recognized as the four major compositions;The optimal extraction method of Folium Isatidis leaf volatile oil was Soxhlet acetone extraction 6h,n-Hexadecanoic acid(8.05%),spathulenol(8.02%),Caryophyllene(6.96%),trans-Squalene(5.33%),beta-Eudesmol(5.34%)ie.were recognized as the major compositions of Folium Isatidis leaf volatile oil;The optimal extraction method of Desmos chinensis leaf volatile oil was same as Cassia leaf,namely acetone extraction 6h under normal temperature,GC-MS analysis the major compositions of Desmos chinensis leaf volatile oil were caryophyllene(9.67%),hexadecanoic acid ethyl ester(9.50%),spathulenol(6.21%),6,10,14-trimethyl-5,9,13-Pentadecatrien-2-one(5.86%),germacreneD(4.20%),?-Cadin ene(3.16%),?-Caryophyllene(2.23%)ie..Base rice wine stater provided by the winery,microorganism separation and purification and identification was conducted by the methods of colony morphology and cell morphology changes of microorganisms,three kinds of mold,two yeast and bacteria were identified.The test of minimum inhibitory concentrations(MIC value)of essential oils from three leaf reveals that Cassia leaf inhabitated the yeast growth,Folium Isatidis and Desmos chinensis leaf inhaibitated the bacteria growth,and the ability of Folium Isatidis leaf inhabitaed the mold growth was the most.Introducing herbal leaves into the substrates was investigated in this study for modifying the physicochemical and biochemical properties of the fermented rice wine inoculum.Adding certain amount of Cassia leafs(0%?1%?9%)had a substantial effect on the microorganism population in the inoculum.With a high Cassia leaf content,growth of molds and their saccharification activities have been promoted while activities of fermentation and esterification decline accompanying with the weakening of total titratable acidity in the inoculum.A total of 7 volatile compounds are found in the fermented rice wine inoculums without Cassia leaf whereas 26 volatile compounds are found in the fermented rice wine inoculums with 9% Cassia leaf,including 4 esters and 3 original volatile flavor compounds from Cassia leaf(trans-cinnamaldehyde,o-methoxycinnamaldehyde,2H-1-benzopyran-2-one)that may contribute to the specific flavor of the wine product.In this work,leaves of Folium Isatidis(0%?4%?9%)were added into fermentation substrate as auxiliary materials to investigate its effect on the starter's physicochemical and biological parameters.The results showed that the Folium Isatidis added could cause the reduction of substrate density,promote the growth of molds and raise the activities of saccharification enzymes,but inhibit the growth of yeasts and bacteria and reduce the activities of fermentability,esterification and liquefying enzymes.Through gas chromatography-mass spectrometry(GC-MS)analysis,it was found that no original volatile compounds from Folium Isatidis remained in the substrate at the end of fermentation,but more volatile compounds were produced in the fermented substrate with Folium Isatidis added,including esters,acids,alkanes,alkenes,amides,alcohols,which would influence the taste and flavour of brewed wine.The mass transfer characteristics,including the moisture content,density,and total titratable acidity of fermentation substrates,were reduced after adding Desmos chinensis leaf(0%?4%?9%).Unlike the vitality of bacteria,the vitality of molds and yeasts and the fermenting and esterifying and saccharified power increased.Through(GC-MS)analysis,two original volatile compounds from Desmos chinensis leaf remained in the substrate at the end of fermentation,namely caryophyllene and alpha-cubebene,and more volatile compounds were produced in the fermented substrate with Desmos chinensis added,especially alkanes,such as heneicosane,heptacosane,hexadecane,octacosane,triacontane,2,4-dimethyl-undecane.