Butter is a dairy product made by churning fresh cream. It consists of an emulsion of water and milk proteins in a matrix of fat. It is solid but soft at room temperature, and melts easily. Its color is generally pale yellow, but can vary from deep yellow to nearly white depending largely on what type of food the animals were eating. Butter is typically paler in the winter, for example, when dairy cattle feed on stored hay rather than fresh grass.



黄油是通过搅拌新鲜奶油制成的乳制品。它由脂肪基质中的水和牛奶蛋白乳液组成。它是固体，但在室温下柔软，容易融化。它的颜色通常是淡黄色，但可以从深黄色到近白色不等，这在很大程度上取决于动物吃的食物类型。黄油在冬季通常较浅，例如，当奶牛以储存的干草而不是新鲜的草为食时。