Sugars and Their Forms

To have a full appreciation of grains, it is vital that you begin to appreciate their value to society. We use grains to make food, drinks, fuel and much more. The value in grain is in it’s stored energy, in the form of starches. Starches are an excellent energy storage molecule, taking sugars produced via photosynthesis and connecting them to form a more stable and storable form of energy.

Sugars are carbohydrates, meaning that they are made of carbon, hydrogen and oxygen. In most situations, sugars exist as rings.

There are many single ring sugars, or monosaccharides, produced by plants, some important ones are shown below. Alpha glucose is the main energy storage sugar, beta glucose can be used for short term energy storage, but is primarily used for structural components in plants, fructose is a common sugar in corn, xylose is a 5 carbon sugar used for energy storage and structure

These single ring sugars can be combined to form 2 ring sugars, or disaccharides. Some common disaccharides are shown below. Maltose is a sugar made from 2 glucoses and is formed when starches are broken down, lactose is a sugar common in milk and is made from one glucose bonded to a related sugar called galactose, sucrose is the main component of table sugar and is made from a glucose bonded to a fructose.

Monosaccharides can be combined into larger structures as well, called polysaccharides. These can be used for structure, long term energy storage, cellular communication, and more. Some important polysaccharides are shown below. Amylose is a straight chain form of starch made of thousands to millions of alpha glucoses and used for energy storage, Amylopectin is a branched form of starch also made of thousands to millions of alpha glucoses and used for energy storage, Dextrin is made from the breakdown of starch into chains of under 100 alpha glucoses. Below these are structural polysaccharides. These are used in plants to create structural components and are often considered as fiber in diets, as humans cannot digest them into simple sugars. Cellulose is made of beta glucose and is used in plant cell walls, and is the most common form of fiber, hemicellulose is made of xylose and related sugars, and is found with cellulose commonly.