Physical-mechanical process for separating or purifying substances such as liquids or gases by means of technical filtering devices. Various filtration methods are a common process in winemaking. Even in ancient times, the Egyptians, Sumerians and Romans had a technique of filtering wine using cloth or similar material. In the Middle Ages, the added aromatic spices were filtered out of the wine with a piece of cloth made of muslin that acted as a filter. This piece of cloth was called the "Manica Hippocratis" ( Hippocrates' sleeve). This was used to make a drink called hypocras, similar to mulled wine, which is still produced today according to an old recipe.