Research Journal of Microbiology1816-4935xxxx-xxxxScience International10.3923/jm.2006.243.254AmizaM. A.ZakiahJ. NgL. K.LaiK. W.3200613The present study reported on the isolation of tempoyak inoculum, pasteurization of durian and tempoyak and microbiological and chemical changes in for pasteurized durian, pasteurized durian inoculated with tempoyak inoculum and natural tempoyak. The isolated dominant lactic acid bacteria (LAB) was grown in MRS broth and inoculated into pasteurized durian. The isolated tempoyak inoculum has the LAB properties i.e. the ability to grow in MRS agar, plate count agar and potato dextrose agar, catalase-negative, gram-positive, rod shaped and may occur in chains. The growth of tempoyak inoculum in MRS broth achieved stationary phase after 24 h. Fermentation of three samples of tempoyak were studied i.e. natural tempoyak (NT), pasteurized durian inoculated with tempoyak inoculum (PDWI) and pasteurized durian (PD). For PDWI, the final LAB count achieved was log 9.1 cfu g-1, which is slightly lower than in NT. After 6 days of fermentation, the final pH value of PDWI is 4.02 and lactic acid content is 2.75%. Meanwhile the pH value of NT was 4.14 and the lactic acid content was 2.36%. The lower acidity in NT might be due to the presence of heterofermentative lactic in the pasteurized durian. D50 and F50 for pasteurization of durian were 4.5 and 32.5 min, respectively. For pasteurization of tempoyak, D50 and F50 were 4.5 and 30.2 min, respectively. Pasteurization of durian and tempoyak at 60 and 70oC is not possible because durian and tempoyak became viscous, due to evaporation of water.]]>Gandjar, I.,20002000pp: 767-773pp: 767-773Garbutt, J.,1997pp: 187pp: 187Ketsa, S. and T. Daengkanit,199873575577Leisner, J.J., M. Vancanneyt, G. Rusul, B. Pot, K. Lefebvre, A. Fresi and L.K. Tee,200163149157Merican, Z.,19771977pp: 147-148pp: 147-148Steinkraus, K.H.,19962nd Edn.,pp: 148pp: 148Suan, C.J.,19961996pp: 148pp: 148William, C.F. and C.W. Dennis,1988pp: 354pp: 354