凍干乳酸菌菌種的研究.pdf

1、東北農(nóng)業(yè)大學(xué)碩士學(xué)位論文凍干乳酸菌菌種的研究姓名：張建友申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：食品科學(xué)指導(dǎo)教師：霍貴成2003.6.1ResearchOiltheFreeze—dryingLacticAcidBacteriaAbstractThestarterisoneofthekeyfactorsinfluencedthefermenteddairyproductsandqualitySweptococuusthermophilus(S^)andL

2、actobacillusbulgaricvs(Lb)werethetwoimportantbacteriaultraconcentrationandfreezedryingLABstarterhassuchadvantagesashighactivity、lessdosageandpolluted、plentykinds、easytransportitionandpreservationHowevertheyareallcommerci

3、allyimported，studyOnthisisnotveryfastandthereisnotasystematicresearchreportyet，thiscertainlywillbringheavierfinancialburdentodairyenterpriseofourcountrySixtrialswereconductedintheexperiment，theobjectiveistoexamthebestLAB

4、andascertaintheoptimumindustrilizationconditionsandthiswillhavegreatecnomicalandfarreachingsocialbenefitsTilefirstexperimentselectthefinebacterialstrainsfromownlabpreservedandgetthesinglecolonyafteralotofactivationsandpu

5、rifications，thenincubaterepeatedly1nthesecondonethreesourcesofcarbon、nitrogenandyeastextractpowderwereoptimizedwithotherssame，itshowedthatthemediumcomponentsofStandL。bwerepancreaspeptone(O5％)、glucose(1％)、yeastextractpowd

6、er(O7％)andpolypeptdn(O5％)、lactose(1％)、yeastextractpowder(O3％)absorbanceat600rimorstandLbwere05325and04732colonywere22X107mL一1and25106mL～respectivelyafterincubation。ThethirdoneshowedthattheoptimalconditionofStisincommonin

7、cubation。4l℃，pH5。6andtheLbiSinC02incubation，37℃，pH58，Inthefourthone，singlefactorexperimentconfirmedfourbettergrowingfactorsofeitheronthisbasis，orthogonaldesignWasusedtostudytheinteractinflunce，Stgrowswellinmushroomuice(1

8、4％)、carrotjuice(10％)、maizefluid(06％)、Vc(O2％)andLbinhaerbinbeer(10％)、tomatoiuice(10％)、carrotjuice(15％)、mushroomjuice(16％)，thecolonyofStandLbwere29X10‰o’and3510SmL～inthismediumThefourmethodswereusedatthesametimeinthefifthe

9、xperimentAbsorbanceat600rimandpHofStand乙bwereO。859、1825and478、407afterultra虹ltration；OD∞oWasincreased50％and20％respectivelyafteraddingphosphatebuffer20％Na2C03Wasaddedintheincubation，thecolonywere10”and109mLl，thebestccntrl

10、fugationconditionWas6000rpmCryoproteetiveagents(1000m1)consistofskimmedmilkpowderl009、monosodiumglutⅫnatelOg、glycerol109，oligosaccharide259、lactose1259，sucrose1259、cystinelg、Vc39afterfreezedryingtheproductswereusedtoferm