Basic Research on the Development of Meat Color control System by Bacteria

Research Project

Project/Area Number	06660341
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Zootechnical science/Grassland science
Research Institution	Kitasato University
Principal Investigator	KONDO Yo Kitasato Univ., School of Vet.Med.and Anim.Sci., Professor, 獣医畜産学部, 教授 (50050381)
Co-Investigator(Kenkyū-buntansha)	ARIHARA Keizo Kitasato Univ., School of Vet.Med.and Anim.Sci., Assistant Professor, 獣医畜産学部, 講師 (00175994) ITOH Makoto Kitasato Univ., School of Vet.Med.and Anim.Sci., Associate Professor, 獣医畜産学部, 助教授 (90050608)
Project Period (FY)	1994 – 1995
Project Status	Completed (Fiscal Year 1995)
Budget Amount *help	¥2,100,000 (Direct Cost: ¥2,100,000) Fiscal Year 1995: ¥600,000 (Direct Cost: ¥600,000) Fiscal Year 1994: ¥1,500,000 (Direct Cost: ¥1,500,000)
Keywords	lactic acid bacteria / meat products / color / Lactobacillus / Enterococcus / gene / myoglobin / Lactobacillus fermentum / メトミオグロビン / ニトロソミオグロビン / オキシミオグロビン
Research Abstract	The color of meat is an important sensory property impacting on consumer acceptability. Meat color is largely dependent on the chemical state of myoglobin. Preventing oxidized myoglobin (metmyoglobin) formation represents one approach for maintaining the quality of meats. In this study, lactic acid bacteria were screened for the ability to convert metmyoglobin to bright red derivatives. Experiments were also conducted to characterize the myoglobin derivatives generated by lactic acid bacteria and the corresponding genes. A total of 510 lactic acid bacteria were screened for the activity. Of510 strains tested, 6 strains (1 Lactobacillus fermentum JCM1173,3 Enterococcus faecalis, 1 E.gallinarum, and 1 E.mundtii) consistently converted metmyoglobin to bright red myoglobin derivatives. The myoglobin derivative formed by the enterococci was identified as oxymyoglobin, whereas L.fermentum generated nitric oxide myoglobin. Efforts are now directing to further identify and localize genetic sequences responsible for metmyoglobin conversion by the transposon mutagenesis techniques. The electrotransformation of L.fermentum JCM1173 with transposon-containing plasmid pHV1248 were successfully attained. Also, the randam insertion of the transposon into the chromosomal DNA of L.fermentum JCM1173 was demonstrated in this study. L.fermentum JCM 1173 worked well to maintain the meat color in the model sausage system. Colloctively, these data indicate that bacterial conversion systems may find utility for improving the appearance of meats during storage.