1、浙江大學(xué)生物系統(tǒng)工程與食品科學(xué)學(xué)院碩士學(xué)位論文乳酸菌高密度發(fā)酵技術(shù)的研究姓名：朱承亮申請學(xué)位級別：碩士專業(yè)：食品科學(xué)指導(dǎo)教師：何國慶20080501麴窶堡堂堂——一一些蘭旦墜竺!———————————————————————————————————————————————————一^1)o■MLIABSTRACTLacticacidbacteriaisonekindofGrampositivebacteriawhichisabletom

2、etabolizecarbohydratesintolacticacid，andusedgenerallyinfoodprocess弱functionalfoodproductsWiththerapidlydevelopmentoffermenteddairyproductindustry，itwillbeveryimportanttostudyhighactivityconcentratedyoghourtstarterculture

3、forpromotingtheindustrialprocessoflacticacidbacteriastarteranddevelopmentoffermenteddairyindustryAshighcelldensitycultureisoIleofthemostlmportantfactorsofmakinghighactivityconcentratedyoghoutstarter，studyonlli幽celldensit

4、yculturewillbeverysignificantandhaveabrightmarketprospeetInthispaper，WeusedsolestrainLactobacillusacidophilus，multi—strainsSthremophilusasandLbulgaricus(1：1)asobjectsBythewayofdiscussingtheeffectsofculturingconditionandm

5、ediacomposition，westudythehighcelldensityculturetechnologyThemainresultswereshowedasfollowing；(1)UnivariateexperimentWasusedtodeterminetheoptimizedcultivationcondltlonSconditionthenresponsesurfacemethodology(RSM)wasappli

6、edtoomlmizethemediumcompositionsTheseexperimentalresultsshowedthattheoptimalculturingconditionswere：pH58，culturetemperature37“C，iinoculumvolume4％，anaerobicculture；theoptimumculturemediumforL口c幻6口cillusacidophiluscomposed

7、of2％wheymist(w／v)，15％beefextract(w／v)15％peptone(w／v)，O058％MgS04(w／v)，0025％MNS04(w／v)，0022％NaAC(w／v)02％K2HP04(w／v)Theamountoflactobacillusacidophiluswasupto37x10兒cfu／mLfor22hoursbasedontheaboveconditions(2)Hi曲celldensityc

8、ultureofmultistrainsSthremophilusasandLbulgaricus(1：1)Wasstudiedinthesameway舔thatofLactobacillusacidophilusBvdiscussingtheeffectsofculturalcondition(temperature，inoculationcapacityandinitialpH)andmediacompositionTheoptim

9、alculturingconditionswere：pH65，culturetemperature40“C，inoculumvolume5％，anaerobicculture；theoptimalculturecompoSltionofwheymist2％(w／v)，beefextract187％(w／v)，peptone1％(w／v)，comup225％(w／v)，MgS040058％(w／v)，MnS040011％(w／v)，NaA