Asian soups are soups traditionally prepared and consumed in the cultures of East Asia. Such soups are usually based solely on broths and lacking in dairy products such as milk or cream. Thickening for the soups usually consists of refined starches from corn or sweet potatoes.Asian soups are generally categorized as either savoury or sweet. The quality of a savoury soup is determined mainly by its fragrance and umami or "xian" flavor, as well as, to a lesser extent, its mouthfeel. Sweet soups such as tong sui are enjoyed for their aroma, mouthfeel, and aftertaste. Many soups are eaten and drunk as much for their flavour as for their health benefits and touted for their purported revitalizing or invigorating effects.