Surmjölk

Surmjölk is a traditional fermented dairy product originating from Sweden. It is made by allowing milk to sour naturally or by adding a starter culture, typically from a previous batch of soured milk or a specific bacterial culture. This fermentation process results in a thickened milk with a characteristic tangy flavor. The texture is similar to yogurt, but the taste profile is distinct due to the specific lactic acid bacteria involved.

Historically, surmjölk was a way to preserve milk before refrigeration was widely available. The souring process inhibits the growth of spoilage bacteria, extending the milk's shelf life. It was a staple in Swedish cuisine, consumed on its own or used as an ingredient in various dishes.

Surmjölk can be made from different types of milk, including whole, skimmed, or even buttermilk, though traditional surmjölk is typically made from cow's milk. The fermentation process transforms lactose into lactic acid, which contributes to its sour taste and thicker consistency. It is often enjoyed with breakfast cereals, as a base for smoothies, or in baking, where its acidity can react with baking soda to provide leavening. While less common in mass-produced dairy sections today, it remains a specialty item and is still produced and consumed in Sweden and by those seeking traditional flavors.