Finding the right temperature for soup can be difficult. On one hand, few culinary experiences are as unsatisfying as sipping on a lukewarm broth. On the other hand, nobody enjoys burning their taste buds to a crisp either! Studies confirm what chefs have long suspected: Temperature affects the taste of food. Cheddar cheese generally tastes more sour when warmed, while a savory ham will seem saltier as it cools. The genes that help express a tomato’s full flavor profile are “turned off” when exposed to cool temperatures. That’s why some cookbooks warn not to refrigerate them. The same principles also apply to soup. Different temperatures can accentuate, or dull, different aspects of a stock’s flavor profile. In short, the hotter the soup (temperature-wise), the more flavorful it can be. It’s important, however, to make a distinction between cooking temperature and serving temperature. Nobody should serve soup at 217°F. Skin exposure to a liquid over 150°F can cause burns almost instantly. High temperature foods also emit more aromas, an important factor that amplifies the intensity of taste. Scientists have done a lot of research about where to draw the line between a liquid that’s “just right” and “too hot”—and a temperature ranging between 136°F to 162°F appears to be the best bet, according to a recent analysis in The Journal of Food Science. For soup-lovers, anything significantly warmer than 170 degrees will probably require tiny sips and spoon-blowing. Anything cooler than 130 might feel merely warm.