in this study, the milk-derived galactooligosaccharides (gos) were produced by lactobacillus delbrueckii subsp. bulgaricus and refined by an ultrafiltration-nanofiltration continuous membrane. by further investigation, we found that the gos product purified by gel permeation chromatography mainly contained low molecular weight disaccharide and trisaccharide, that is, 4-β-galactobiose and tri-ga...
