The byproducts usually contain carbohydrate, in such byproducts as corn steep water, molasses or milk whey, proteins and lipids in animal tissues and cereal grains, and lipid in greases and oils.

• 农业副产品通常包含碳水化合物等物质，例如，谷物浸泡水，糖蜜和牛奶乳清， 动物组织中的蛋白质，脂质以及谷物，还有油脂中的脂质和油。