Abu Sa'id Al-Khudri (May Allah be pleased with him) reported:
Messenger of Allah (ﷺ) prohibited us blowing in the drinking water. A man said: "O Messenger of Allah! Sometimes I see some litter floating about on the surface. What should I do then?" He (ﷺ) replied, "Pour them out." Then the man said: "My thirst is not quenched with one draught." Messenger of Allah (ﷺ) said, "Then put away the cup from your mouth (in between three gulps), and take breath."[At-Tirmidhi]. (DE)
App reference (DE): Book 3, Hadith 38 (DE)
Arabic/English book reference (DE): Book 3, Hadith 765 (DE)