Carbohydrates

1
Carbohydrates

• A major component of most diets

2
Carbohydrates

• Provide 52 of calories in American diet
• Complex carbohydrates (needed in diet!)
• Large molecules, Starches
• Fibers
• Simple carbohydrates (watch it!)
• Monosaccharides
• Dissacharides

3
How to Make/Break a Polymer
4
Simple Sugar
5
Monosaccharides
6
Most Common Monosaccharides in the Diet

• Galactose
• Does not occur in diet as monosaccharide
• Most often a part of lactose, milk sugar
• Fructose
• Fruits, veggies, honey
• Glucose
• Most important source of energy
• Usually occurs in disaccharide or starch

7
Constructing Disaccharides
8
Most Common Disaccharides

• Maltose
• Glucose glucose
• Sweet taste of bread (amylase)
• Sucrose
• Table sugar
• Sugar in food labels
• Lactose
• Only sugar found in animal food
• 30 of energy in cows milk

9
Stored Carbohydrates
10
Digestible or Not
11
Cellulose
12
Complex Carbohydrates

• Consist of many monosaccharides
• Oligosaccharides (3-10 mono)
• Found in beans other legumes
• Cannot be digested by humans
• May cause gas and discomfort (Bean-O)
• Polysaccharides
• Glycogen stored in muscles, liver
• Terminal mono is removed quick energy supply
• Starch stored in plants
• Amylose, amylopectin

13
(No Transcript)
14
Complex Carbohydrates Cont. Dietary Fiber

• Plant materials that cannot be digested
• Insoluble fibers
• Not soluble in water
• Cellulose, hemicellulose, lignin
• Wheat, rye bran celery, broccoli
• Soluble fibers
• Dissolve in or absorb water
• Pectins, gums
• Oats, apples, beans, psyllium (used in
  bulk-forming laxatives like Metamucil)

15
Why does fiber matter?

• Foods high in fiber stay in gut longer, leaving a
  feeling of fullness and satisfaction.
• High intake of fiber evens out blood glucose
  levels.
• May reduce chances of colon cancer.
• Lowers cholesterol level by 20 or more.
• Promotes gastrointestinal tract functions.

16
Complex Carbohydrates in Diet

• Grains
• Rice, corn, oats, wheat, barley
• Legumes (pods with rows of seeds)
• Peas, lentils, soybeans, kidney beans (starchy
  seeds)
• Vegetables
• Starchy veggies sweet white potatoes, yams,
  cassava
• Veggies such as green beans, broccoli have small
  amount of starch, lots of vitamins, fiber,
  minerals.

17
Whole Refined Grains

• Seed consists of bran, germ, endosperm
• Bran fiber, Vit B
• Germ embryo, source of veg oils Vit E
• Endosperm Starch (embryo food supply) protein,
  some vit, minerals
• Whole grain contains all parts
• Brown rice, whole wheat flour, rolled oats
• Refined flour bran, germ are removed

18
Whole Grain Foods
Corn
wheat
Oats
19
Whole Grain Rice
20
Refined Flours

• Mainly endosperm of grain
• Vitamins lost in process
• Some nutrients added back to flours

21
Simple Carbohydrates

• Sugars 21 of American diet
• Sugars added to food as sweetner
• Sucrose is refined from sugar beets, sugar cane
• Other processed sugars honey, maple syrup,
  brown sugar, molasses
• Sugars added in food manufacturing
• Sucrose, fructose, high-fructose corn syrup, corn
  syrup, maltose

22
Lactose Intolerance

• Reduced ability to digest lactose (milk sugar)
• Occurs in many people with age
• Causes digestive upset, bloating
• Eat tofu, fish, calcium-rich veggies, Ca
  supplement, milk treated with the enzyme lactase,
  lactase tablets

23
Functions of Carbohydrates

• Energy (glucose)
• 4 kcal/g
• Make up many macromolecules
• RNA, DNA
• Found on cell surfaces as part of signal systems
  for proper function of cells