Carbohydrate The term carbohydrate was originally used to describe compounds that were literally “Carbon Water" or hydrates of carbon because they had the base formula of CH2O. But now they are named based on their chemical structure

Basic Composition C,H,O Basic formula you can use: CnH2nOn Most Common Carbohydrates Monosaccharides: glucose, fructose, galactose Disaccharides: sucrose, lactose, maltose Polysaccharides: plant starch- amylose and cellulose animal starch- glycogen

Tiny Differences Tiny differences in the number, arrangement, and type of monosaccharides can affect a carbohydrates: 1. Taste 2. Texture 3. Biological activity

3 Factors determining differences The length of Carbon Skeleton (# of Carbons) The less carbons in the carbon skeleton the sweeter the taste

2. Where its Carbonyl group is located (Oxygen) If the double bond is at the end of the molecule is will be an Aldehyde If the double bond is in the middle of the molecule is will be an Ketone

3. *Orientation of the atoms All sugars are sweet because they contain OH groups with a particular orientation that can interact with the taste receptor for sweetness in our tongues. Sweetness is related to a substance's ability to hydrogen bond to a protein-based receptor in taste buds at the tip of the tongue.

Your Task Look at the structural diagrams to figure out how these sugar characteristics affect sugar taste Determine if there is anything else that can affect how we ‘taste” the sweetness of sugars.

Lab 2E-Structure of Carbohydrates Sucrose = Green Glucose (Dextrose)= Blue Fructose= Purple Galactose= Red Maltose= Yellow Lactose=blank Starch= Green/Blue Cellulose=Purple/ Red