A simple sugar, C₆H₁₂O₆, stereoisomeric with glucose (see monosaccharide). (Although natural fructose is the d-form, it is in fact laevorotatory.) Fructose occurs in green plants, fruits, and honey and tastes sweeter than sucrose (cane sugar), of which it is a constituent. Derivatives of fructose are important in the energy metabolism of living organisms. Some polysaccharide derivatives (fructans) are carbohydrate energy stores in certain plants. Fructose derived from corn starch is now used extensively in food manufacturing as a sucrose substitute, for example in soft drinks, canned fruit, and jams.