Carbohydrates

Carbohydrate What is a carbohydrate? Carbo refers to the presence of carbon Hydro refers to the presence of water which is a combination of hydrogen and oxygen Carbohydrates are then made up of ……?

What is a carbohydrate cont… Carbohydrates are one of the six most essential nutrients They are your body’s main source of energy Carbohydrates = the sugars, starches, and fibers in your diet. About 55 to 60 percent of your daily calories should come from carbohydrates.

What is a carbohydrate cont… Carbohydrates cannot be produced by animals, only green plants. Photosynthesis - The process in which plants use the suns energy to convert carbon dioxide and water into carbohydrate and oxygen The plant produced carbohydrate is glucose Plant can convert the glucose molecules into other sugars, starches, or fiber

Types of carbohydrates Simple carbohydrates a carbohydrate that consists of a single monosaccharide unit (single sugar unit). Such as monosaccharides or disaccharides. Found naturally in small amounts of food Candies, cookies, soft drinks, jams, jellies High in calories and provide little or no nutritional value

Types of Carbohydrates Complex carbohydrates a carbohydrate that consists of two or more monosaccharide units (long chains of sugar unit). Such as polysaccharides, starches or fibers. For good health you should focus on complex carbohydrates Dry beans/peas, rice, grits, breads, cereals

Sugars Can be defined as a sweet crystalline carbohydrate. The correct term being “saccharide” Sugar molecule is a hydroxyl group 6 carbon 12 hydrogen 6 atoms Combination of hydrogen and oxygen

Properties of Sugar All have same chemical formulas, they differ in how the atoms are positioned in the molecular ring The difference in arrangement causes a difference in sweetness, solubility, & other factors

Monosaccharides composed of single sugar units (mono means 1). Smallest of all carbohydrate molecules. 3 types of monosaccharides Glucose – the building blocks of carbohydrates Single sugar used in plant and animal tissues as quick energy (blood sugar) Fructose – sweetest of single sugars Galactose – bonded to glucose in the sugar of milk

Disaccharides Composed of 2 sugar units (di means 2) There are 3 types of disaccharides Sucrose – double sugar composed of glucose and fructose (Glucose + fructose) Maltose – double sugar composed of two glucose units (Glucose + glucose) Lactose – double sugar composed of glucose and galactose (milk sugar) (Glucose + galactose)

Polysaccharides composed of many sugar units (poly meaning many) There are only 2 types Starches – from plants. Composed of glucose, digestible by human beings Fibers – indigestible residue of food

Starches AMYLOSE AMYLOPECTIN Most important job is as a thickening agents. Have 2 structures: AMYLOSE Found in rice and in wheat flour Best ability to set as a gel AMYLOPECTIN Less easily mixed with water, Ex. potatoes and tapioca

Other Benefits of Fiber Soluble Fibers Dissolve easily in water Beans, peas, oats, rice Insoluble Fibers Do not dissolve in water. Take on characteristics of a sponge Whole wheat, rye, bananas

Other Benefits of Fiber Plant fiber eaten in food is cellulose, cell walls & woody parts of plants Human can’t digest, we don’t have enzyme to do so Fiber absorbs water and swells, moves along intestines = keeps bowels functioning normally and regularly Foods include fruits, vegetables, nuts, and whole grain breads & cereals

The functions of carbohydrates There are 4 key functions Produce Energy Spare Proteins Break Down Fats Provide Bulk in the Diet

How Your Body Uses Carbohydrates All carbohydrates must be in the form of glucose All absorption occurs in the small intestine where it is then carried to the liver Insulin Helps the body lower blood glucose Glycogen The body’s storage form of glucose