Clarified butter has a fat content of almost 100% and it is concentrated butter. Clarified butter is lactose free and free from milk protein, lactose and water. Clarified butter is used for cooking, baking and frying.

The butter is melted and milk protein, milk sugar and water are separated by centrifugation. The rest remains of water is removed in a boiler under vacuum and then the mass is whipped with air and bottled. 

https://de.wikipedia.org/wiki/Butterschmalz