Agar, as a natural marine polysaccharide-refined agar, is extracted from seaweeds and refined by special processing. In Japan, as a food material and a heath food which are rich in dietary fibers, agar is widely used in yoghurt, jellies, cakes and other foods. Agar has health function of supplementing dietary fibers. As an emulsion stabilizer, Agar has distinguished properties of quick-dissolving with low-heat and emulsifying,gelling,suspending and taste-improving etc. Different from ordinary agar which can not dissolve without boiling for 10-15 minutes and produces turbid solution,Agar can dissolve within 5-7minutes from 55℃ to 60 ℃ and produces solution with high grade of transparency. Therefore, Agar can be conveniently used in the production of yoghurt without pre-heating,which can save power for heating at a great rate for the producers. Comparing with imported agar, Agar has same or even better properties. It is applicable to acidized milk and can improve the structural forms of stirred milk because it is effectively resistant to mechanical shearing. Agar makes yoghurt rich in mouth-filling,smoothness and delicateness with better feeling of piling up and flavor release. Furthermore,Agar can prevent yoghurt from whey-separating during the shelf life of yoghurt and makes yoghurt stable,therefore,to improve the quality of yoghurt.