Growth and survival of cheese ripening bacteria on milk fat globule membrane isolated from bovine milk and its monosaccharides

The growth and survival of cheese lactic acid bacteria (LAB) on milk fat globule membrane (MFGM) isolated from bovine milk and on monosaccharides found in MFGM glycoconjugates were studied. The LAB studied were selected lactobacilli strains isolated from Norwegian semi-hard cheese, a starter Lactococcus sp. and the potential cheese contaminant Enterococcus hirae. The bacteria were able to grow on MFGM isolated from bovine milk and to utilize several of the monosaccharides found in the MFGM. Only one strain of lactobacilli was able to utilize N-acetyl-d-galactosamine for growth. Growing lactobacilli on the acylated aminosugars N-acetyl-d-glucosamine or N-acetyl-d-galactosamine induced a decrease in the number of culturable bacteria at an earlier stage than when grown on any of the other monosaccharides. The potential cheese contaminant Ec. hirae showed superior growth and survival abilities compared with the other lactic acid bacteria when grown on the MFGM media and on several of the MFGM monosaccharides.