This study was attempted to determine the effects of alginate β-galactosidase beads on oligosaccharides biosynthesis in milk and on the quality of yoghurt made by the milk. Two percent Na-alginate solutions were used to produce alginate β-galactosidase beads. Those alginate beads with or without β-galactosidase were added to the milk to produce oligosaccharides. Total sugars, pH value, titrable acidity, curd hardness, lactic acid bacterial counts and sensory evaluation were determined. The results showed milk treated with alginate β-galactosidase beads (the treatment) had higher oligosaccharide contents than the control (milk treated with alginate beads but containing no β-galactosidase). During 6 hr fermentation, the pH values of all yoghurt decreased with a prolonged fermentation period, but the treatment had lower pH than the control at 6 hr. However, the treatment had higher titrable acidity than the control at 6 hr. In addition, the treatment had higher lactic acid bacterial counts than the control during the fermentation period. No significant difference was observed in curd hardness and sensory evaluation between the treatment and the control. In conclusion, yoghurt made from alginate β-galactosidase beads had not only had higher lactic acid bacterial counts, but also a shorter the coagulation time than the control.
This study was attempted to determine the effects of alginate β-galactosidase beads on oligosaccharides biosynthesis in milk and on the quality of yoghurt made by the milk. Two percent Na-alginate solutions were used to produce alginate β-galactosidase beads. Those alginate beads with or without β-galactosidase were added to the milk to produce oligosaccharides. Total sugars, pH value, titrable acidity, curd hardness, lactic acid bacterial counts and sensory evaluation were determined. The results showed milk treated with alginate β-galactosidase beads (the treatment) had higher oligosaccharide contents than the control (milk treated with alginate beads but containing no β-galactosidase). During 6 hr fermentation, the pH values of all yoghurt decreased with a prolonged fermentation period, but the treatment had lower pH than the control at 6 hr. However, the treatment had higher titrable acidity than the control at 6 hr. In addition, the treatment had higher lactic acid bacterial counts than the control during the fermentation period. No significant difference was observed in curd hardness and sensory evaluation between the treatment and the control. In conclusion, yoghurt made from alginate β-galactosidase beads had not only had higher lactic acid bacterial counts, but also a shorter the coagulation time than the control.