The process of acidifying fresh milk transforms it into a thickened, tart liquid. This transformation is typically achieved through the introduction of an acidic agent, like lemon juice or vinegar, or by allowing naturally occurring bacteria to ferment the lactose present in the milk. The resulting product exhibits a different texture and flavor profile compared to its original state.
This alteration extends beyond mere culinary modification. In cooking, it can act as a buttermilk substitute, lending tenderness and a subtle tang to baked goods. Historically, this method was a vital means of preserving milk before widespread refrigeration, allowing utilization of the dairy product even as it began to change naturally. The process also offers advantages in cheesemaking and other food preparations, where acidity is a desired characteristic.