If one sees straw or something like that in the water-vessel, he should not blow in the water. Messenger of Allah (PBUH) has forbidden it. Instead, some of the water or all the water should be poured out. Also, if his thirst is not quenched in a single breath, one should remove the vessel from his mouth. After taking breath, he should again drink water. To drink water in three breaths is preferable. However, in case of hot tea or milk, sipping is permissible, no matter if sips are in plenty.