If a child drinks spoiled milk, rinse his mouth with water. If you have taken a drink of spoiled milk, swish water in your mouth and spit out several times and then brush your teeth to remove the taste. Milk is a highly nutritious, but is a perishable food containing protein, fat and sugar. The child may vomit initially because of the bad taste of the milk, but he will usually not develop a foodborne illness, according to The Stir. Medical care is recommended if the child develops diarrhea, fever or prolonged vomiting. After cleaning your mouth, drink some water to help dilute out any residue. As long as the milk isn’t moldy, you can use it for baking breads and cakes, as well as marinating meats. If, however, you pour the spoiled milk into your Lucky Charms, smoothie, or protein shake, and gulp it down… there’s no gentle way to say this: you will likely get food poisoning. While you certainly shouldn’t drink a glass of spoiled milk by itself, it’s not entirely a lost cause.