Saco Cultured Buttermilk Blend is a convenient alternative for liquid buttermilk or sour milk in any recipe. Saco Buttermilk, 12 oz, is made out of a cultured blend of churned buttermilk, sweet cream, dairy whey and lactic acid. This low fat buttermilk is suitable for many people with food allergies, as it is free from tree nuts and peanuts. This buttermilk blend is also gluten free.