Making Cottage Cheese from Sour Milk
from https://www.theselfsufficienthomeacre.com/

"Making cottage cheese from sour milk is a great way to reduce waste, save money, and get some extra protein in your diet. My Mom always used sour milk in baked goods for light and fluffy cakes, muffins, and even pancakes. I’ve used sour milk in place of buttermilk or regular milk in recipes, but it’s nice to have another option.

I have found several sites online that gave instructions for making cottage cheese from sour milk, but they didn’t say how sour your milk can be and still be usable for cottage cheese. I’ve found that it can be curdled, but if it is really horrible smelling… I dump it to be on the safe side.

If you are concerned about using sour milk to make cottage cheese, I understand and you can use this recipe to make cottage cheese from fresh milk instead. Keep in mind that heating the sour milk to 195F [185F] and holding it there for 10 minutes should kill harmful bacteria."

Old Fashioned Cottage Cheese

half gallon sour milk (whole is best) or fresh milk [not ultra-pasteurized]
1 Tbs [white] vinegar
1/2 tsp salt
a small amount of cream or whole milk (not sour)

Pour sour milk into a saucepan. Turn heat on to medium and use a candy thermometer to measure temperature. [Slowly] Heat milk to 195 F. [185 F.]

[Be careful not to let the milk get hotter than that since too much heat delivered too fast could change the texture of the curds and make them rubbery. Low & slow heat is best.]

Remove from heat and add vinegar. Stir gently until curds and whey separate.

[If you don’t get the separation you are looking for, add another tablespoon of vinegar after a couple of minutes of stirring. You want the remaining whey to be almost clear.]

Pour through a colander lined with cheesecloth. Let the curds drip until the whey is all drained off. [The whey can also be used as broth to add to soups or breads, but remember you added vinegar or lemon juice to it.]

Rinse the curds and squeeze the water out through the cheesecloth. Pour curds into a bowl. Crumble to the size curds you like.

Add salt and a small amount of cream or whole milk. Stir and add more milk or cream until your cottage cheese is the consistency you like.

Refrigerate and use within 1 week.

Makes about 1 cup