1. 1 Chapter 3 Carbohydrates

2. 2 Photosynthesis Plants can make their own carbohydrates from the carbon dioxide in the air and water taken from the soil. Photosynthesis converts energy from sunlight into energy stored in carbohydrates, which the plants uses to grow and be healthy.

3. 3 Categories of Carbohydrate Simple carbohydrates Natural sugars Added (Refined) sugars Complex carbohydrates (polysaccharides) Starch Fiber

4. 4 Functions of Carbohydrate Functions as primary source of body’s energy Central nervous system and red blood cells rely almost exclusively on glucose. Glucose is stored in liver and muscles as glycogen. Spares protein from being burned for energy Helps body use fat efficiently Part of various materials in body, such as connective tissue, some hormones & enzymes, and genetic material

5. 5 Monosaccharides and Disaccharides

6. 6 Relative Sweetness of Sugars and Artificial Sweeteners SweetenerRating Sugars Lactose20 Glucose70 – 80 Sucrose100 High-fructose corn syrup120 – 160 Fructose140 Artificial Sweeteners Aspartame (Nutrasweet, Equal)160–220 Acesulfame-K (Sunette)200 Saccharin (Sweet ’N Low)200 – 700 Sucralose (Splenda)600 Neotame7,000–13,000

7. 7 Added Sugars Added sugars: Sugars added to a food for sweetening or other purposes, do not include natural sugars Examples: Granulated white sugar, high fructose corn syrup

8. 8 Sugars on the Nutrition Facts Label The number of grams of “Sugars” includes both natural and added sugars. To find out if a food contains added sugar, look at the ingredient list.

9. 9 Examples of Added Sugars White sugar (sucrose) High-fructose corn syrup or corn syrup Invert sugar Brown sugar Molasses Honey Powdered sugar Raw sugar Demerara sugar

10. 10 Added Sugars and Health Dental caries (sugar & starch) Obesity Diabetes Heart Disease Hypoglycemia Hyperactivity in Children

11. 11 Glycemic Response How quickly and how high your blood sugar rises after eating. Eating mainly foods with a low glycemic response is important for people with diabetes and seems to decrease the risk of heart disease, type 2 diabetes, and colon cancer, as well as enhancing weight management.

12. 12 Glycemic Index Glucose Corn flakes Waffles, French-fried potatoes, jelly beans Bagel, white bread White sugar, cantaloupe Raisins, tortilla chips, cola soda, ice cream, pizza Rye bread Orange juice Fresh orange, peas, carrots Fresh peach, old-fashioned oatmeal, apple juice White rice, spaghetti, apple, pear, tomato soup Skim milk, low-fat yogurt Kidney beans Grapefruit Soybeans Peanuts

13. 13 Lactose Intolerance An intolerance to milk and most milk products due to a deficiency of the enzyme lactase. Symptoms often include flatulence and diarrhea within 30 minutes to 2 hours. Especially prevalent among Asian Americans, Native Americans, African Americans, Latinos, and other groups. Treatment requires a diet limited in lactose. Most people can drink small amounts of milk especially if taken with food.

14. 14 Complex Carbohydrate: Starch Made of a long chain of glucoses linked together. The glucose chains may be straight (amylose) or branched (amylopectin). Found only in plant foods: grains, legumes, vegetables, some fruits. Most starchy foods are cooked to make them flavorful and able to be digested. Gelatinization – When starches are heated, they absorb water and swell in size.

15. 15 Structures of Starch and Glycogen

16. 16 Fibers Polysaccharides found in plant foods that the body can’t digest or absorb. Some fiber is digested by bacteria in the large intestine. Two types: soluble or viscous fiber insoluble or nonviscous fiber

17. 17 Food Sources of Fiber Soluble fiber 1. Fruits 2. Legumes 3. Oats, barley, and rye 4. Also seeds and vegetables Insoluble fiber 1. Wheat bran, brown rice, whole grains 2. Vegetables (cabbage, carrots) 3. Fruits 4. Legumes

18. 18 Health Effects of Fiber Soluble, viscous fiber Lowers risk of heart disease & stroke by: Binding bile Lowers risk of diabetes and controls diabetes by: Slowing glucose absorption Also holds moisture in stools, softening them Insoluble, nonviscous fiber Alleviates constipation and lowers risk of hemorrhoids and diverticulosis by: Increasing fecal weight and speeding fecal passage through the colon May help with weight management

19. 19 If you decide to eat more fiber….. Do so slowly and Drinks lots of fluids to give time for your intestine to adapt.

20. 20 Whole Grains Examples: Whole wheat Whole rye Oatmeal Whole oats Whole hulled barley Popcorn Brown rice Whole grains offer: More nutrients Phytochemicals More fiber Dietary Guidelines for Americans recommends 3+ servings of whole grains each day.

21. 21 Digestion, Absorption, & Metabolism of Carbohydrates Starch digestion begins in mouth. (enzyme- salivary amylase) Before being absorbed, carbohydrates must be broken down into monosaccharides. Enzymes in small intestine (sucrase, lactase, maltase, and pancreatic amylase) ensure that single sugars are absorbed. In the liver, fructose and galactose are converted to glucose or further metabolized to make glycogen or fat.

22. 22 Dietary Reference Intakes RDA for carbohydrate – 1 year old + 130 grams daily (minimal amount – you really need 2x) AMDR – 1 year old + 45-65% of kcalories AI for total fiber 14 g/1000 kcal Men 19 – 50 years old38 g Men over 50 years old30 g Women 19 – 50 years old25 g Women over 50 years old21 g DRIs – added sugars < 25% of total kcalories

23. 23 Low-Carb Foods To reduce carbohydrates, manufacturers: Substitute soy flour, soy protein, or wheat gluten (all higher in protein) for refined flour Substitute artificial sweeteners and/or sugar replacers (also called polyols) for sugars Add fiber such as wheat bran Add high-fat ingredients such as nuts to improve flavor and/or add bulk

24. 24 5. Sugar Replacers or Polyols A group of carbohydrates that are sweet and occur naturally in plants. Examples: sorbitol, xylitol found in sugar- free gums and candy.

25. 25 5. Sugar Replacers or Polyols Benefits: Don’t provide as many kcalories as sugar – only about 2 kcal/gram. Don’t promote tooth decay. Taste sweet – though not as sweet as sugar. Add bulk and texture to foods. Cause smaller increases in blood sugar and insulin than sugar. Side effects

26. 26 Sugar Replacers or Polyols Sugar Replacer Kcal/gramUsesDescription* Mannitol1.6Chewing gum, powdered foods, chocolate coatings 50 to 70% as sweet as sugar. May causes a laxative effect when 20 grams or more are consumed Does not absorb moisture so it works well as a dusting powder for chewing gum so the gum doesn’t stick to the wrapper. Sorbitol2.6Candies, chewing gum, baked goods, frozen desserts 60% as sweet as sugar. gum, baked goods, May cause a laxative effect when 50 frozen desserts grams or more are consumed. Cool, pleasant taste.

27. 27 Sugar Replacers or Polyols (cont’d) Xylitol2.4Chewing gum, candy As sweet as sugar. Pleasant taste. Erythritol0.2Beverages, chewing gum, candy, baked goods Newest polyol. Very heat stable. Much less of a laxative effect than other polyols. Works well with other sweeteners to improve flavor and body. Isomalt2.0Candies, toffee, fudge, wafers 45 to 60% as sweet as sugar. Used to add bulk and sweetness to foods. Very heat stable. Works well with other sweeteners to improve flavor.

28. 28 Sugar Replacers or Polyols (cont’d) Lactitol2.0Chocolate, candies, cookies and cakes, frozen dairy desserts. 30 to 40% as sweet as sugar. Mild sweetness with no aftertaste. Used to add bulk and sweetness to foods. Works well with artificial sweeteners. Maltitol2.1No-sugar added ice cream, low- carb bagels, candy, chewing gum, chocolate, baked goods. 90% as sweet as sugar. Used to add bulk and sweetness to foods.

29. 29 Sugar Replacers or Polyols (cont’d) Hydrogenated Starch Hydrolysates 3.0Candy, baked goods 25 to 50% as sweet as sugar. Used as bulk sweetener in low calorie foods. Performs other functions in foods as well. Can mask unpleasant off-flavors. Blends well with flavors. Works well with other sweeteners. *All sugar replacers have the following characteristics: Occur naturally. Don’t provide as many kcalories as sugar. The average kcalories per gram is 2, compared with 4 kcalories/gram from sugar. Don’t promote tooth decay. Cause smaller increases in blood glucose and insulin levels than sugar.

30. 30 Nutrition facts and ingredients for sugar-free chocolate bar

31. 31 Artificial Sweeteners Approved Saccharin Aspartame Acesulfame-K Sucralose Neotame Possibilities Alitame Cyclamate Stevioside Reduced-Kcal Sweetener Tagatose

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