Fructose

Fructose is a common monosaccharide, classified as a reducing hexose and more specifically a ketonic simple sugar, that occurs in nature often bonded to glucose to form sucrose and exists as a white, water soluble solid. It is found in honey, tree and vine fruits, flowers, berries and most root vegetables, and is one of the three primary dietary monosaccharides humans consume, alongside glucose and galactose. Fructose is unusually sweet, with its relative sweetness reported at 1.2 to 1.8 times that of sucrose, making it the sweetest naturally occurring carbohydrate, though sweetness varies with temperature since its six-membered ring form tastes considerably sweeter than its five-membered ring form. Because of its high relative sweetness and low cost, industries use it extensively in food manufacturing, drawing on sources such as refined sugar, high-fructose corn syrup, agave products, maple syrup and fruit juices; it provides about 95 percent of sucrose's caloric value per unit weight.