Separated And Screened Of The Starter From Yunnan Ham And Applied To Fermented Ham

In this research strains such as lactic acid bacteria,Micrococcus,Staphylococcus wereisolated and screened from yunnan ham.After capacity of acid and growth were tested,7 strains with excellent characteristics were selected and preliminary identified,2 lactic acid bacteria 1Micrococcus and 1 Staphylococcus,As starter the strains were applied to fermented ham and their mechanism of action were discussed.The report including several parts as follows:1.47 stains of Gram-positive and 55 stains of Gram-positive cocci were isolated from yunnan ham with MRS agar and MSA agar.Based on the standards of screening Staphylococcus actic acid bacteria,Micrococcus and Staphylococcus for fermented meat product,four stains of lactic acid bacteria including YN4,YN17,YN23 and YN37and four stains of Gram-positive cocci such as XW13,XW21 and XW34 were screened.The four stains of lactic acid bacteria did not produce CO₂ from glucose,H₂S,NH₃ fromarginine,H₂O₂ and slime.They also had no decarboxylase activity and they can resist nitrite and Nacl.Acidificaction rate and acidifying capacity of them were better than others.E.coli and S.aureus were inhibited by them.YN4,YN17,YN23and YN37 displayed nitrate reduction,catalase-positive,protease and lipase activity beyond some characteristic of XW13,XW21 andXW34.2.Based on phenotype and biochemical characteristic YN4 and YN23were preliminary identified as P.pentosaceus;YN17 and YN37were preliminary identified as L.sake;XW13 and XW34were preliminary identified as S.xylosus;XW21were preliminary identified as M.varians;3.According to secure test,XW13 and XW34 are safety.As can be mixed with lactic acid bacteria and fermented to fermentament ham.4.Fermented ham was produced with the selected strains and their mechanism of action was discussed after changes of microbial succession,physical-chemical properties,biochemistry properties were studied.The catalase that M.varians and S.xylosus produced can prevent the oxidation of lipid significantly and the multiplication of M.varians and S.xylosus can improve color significantly.Relatively speaking,endogenous enzyme is more important to proteolysis and lipase,microbial enzymes did their work faintly.