Sour milk is a substitute for buttermilk in baked goods. Sour milk is also used as a starter ingredient for yogurt and cheese making, so knowing how to make sour milk at home is useful. Either vinegar or lemon juice mixed with milk will sour it.
Step One
Measure 1 cup milk into the pitcher.
Step Two
Add 1 tbsp. of lemon juice or vinegar to the milk.
Step Three
Stir with fork for 30 seconds.
Step Four
Set the timer for five minutes. Use the sour milk when the timer goes off.