 Now, there is such a thing as cultured butter, also known as Danish-style butter. It actually has a culture added to the cream before it is churned. It is kept at a controlled temperature, usually overnight, so that this slightly acidic flavor develops. And then according to European tradition, no salt is added after draining the buttermilk. And I think it's an acquired taste and delicious. You can also find cultured salted butter, typically Australian, not European. It has salt added with the culture.