1. Monosaccharides Disaccharides
Simple Carbohydrates
Monosaccharides
Disaccharides

2. Monosaccharides
Variety of shapes and sizes due to number and arrangements of atoms
Hundreds of naturally occurring monosaccharides
Only three are commonly found in food (6 carbon atoms)
Monosaccharides have a variety of shapes and sizes because the number and arrangements of atoms can vary. There are hundreds of naturally occurring monosaccharides, but the three most commonly occurring are glucose, fructose and galactose. The structures of these differ, but have one thing in common: each contains six carbon atoms.
NTK: molecular formula & structural formula

3. Glucose Most abundant monosaccharide
Carbon dioxide + water  glucose + oxygen
Functions
ATP – immediate use
Amino acids (proteins)
Glycogen/starch (storage form of carbohydrates)
Lipids – long term storage
Preferred energy source for the nervous system and the sole source of energy for RBC
Photosynthesis = light energy  chemical energy (glucose)
Respiration = chemical energy (glucose)  usable chemical energy (ATP)

4. Fructose Found in honey, fruits and vegetables
Five-sided ring structure (hexose)
High-fructose corn syrup HFCS
Derived from corn (Food Inc.)
~7% of total energy intake in the US
35lbs/15kg of HFCS per year per American
Obesity epidemic in the US

5. Galactose
Structurally similar to glucose except for the hydroxyl group on the fourth carbon
Found in few food – mostly in lactose
Functions
Components of cell membrane
Synthesis of breast milk
Majority is converted to glucose

6. Disaccharides Glucose is a component in all three disaccharides
2 C6H12O6  C12H22O11
Condensation reaction
Glycosidic bond between -OH and –H
Types of glycosidic bond determine if a carbohydrate is digestible or indigestible
Alpha-glycosidic bond can be digested while beta-glycosidic bond cannot

7. Lactose
Enzymes in mammary glands combine glucose and galactose
The only disaccharide with a beta glycosidic bond
Maltose
Not found in many food, only during starch digestion
Enzymes breakdown starch  maltose then bacteria ferment maltose  beer
Sucrose
Found in sugar cane and sugar beets, processed and crystallized to form sucrose or table sugar

8. Sugar in Foods Sweetens Thickens Alter textures
Naturally occurring sugars are more nutrient dense then artificial ones
Limited in nutrition value other than energy
~89 g/22 tsp/355 kcal per day per American
Good Eats
Functions of sugar includes fermentation, preservation, tenderization, hydrolyzation, etc.

9. Complex Carbohydrates
Oligosaccharides
Polysaccharides

10. Oligosaccharides Found in dried beans, soybeans, peas, etc.
Indigestible by humans
Functions
Components of cell membrane
Incorporated into human breast milk
If oligosaccharides cannot be digested and absorbed by humans, how do we get them for cell membrane?
Humans lack the enzymes needed to digest these two carbohyrateds, they pass undigested into the large intestine, where bacteria break them down. As a result, some people experience abdominal discomfort (bloating, crams and gas) due to the methane and acid produced as waste products. Commercial products such as Beano supply enzyme needed to break down oligosaccharides.

11. Polysaccharides Examples of polysaccharides? Glycogen – in animals
Starch – in plants
Cellulose – in plant cell wall (fiber)

12. Starch Amylose – linear Amylopectin – branched
alpha-1, 4 glycosidic bonds
Amylopectin – branched
alpha-1, 4 in the linear portion
alpha-1,6 in the branch joints

14. Uncoiled for a Closer Look

15. Glycogen Glycogen - branched Stored in
alpha-1, 4 in the linear portion
alpha-1,6 in the branch joints
Stored in
Liver
Skeletal muscles

16. Cellulose Cellulose - linear
Opposite orientation
beta-glycosidic bonds
Digestible by intestinal bacteria
Total fiber = dietary fiber + functional fiber
Soluble and insoluble dietary fiber

17. Cellulose Soluble Fiber – absorbs water like a sponge Insoluble Fiber
Softens feces (otherwise all water will be absorbed by the body)
Binds to cholesterol
Slows down gastric emptying (feeling full)
Insoluble Fiber
Increase amount of feces, so body eliminates them sooner

18. Starch can be linear or branched
Cellulose is linear, with monomers in opposite orientations due to beta-glycosidic bonds
Glycogen is always branched

19. Diverticulitis Low fiber diet Hard, dry feces Damage mucosa
Weak mucosa layer
Diverticula form
Inflamed diverticula
Diverticulitis

21. FDA-approved Health Claims
“Diets low in fat and rich in high-fiber foods may reduce the risk of certain cancers.”
“Diets low in fat and rich in soluble fiber may reduce risk of heart disease.”
“Diets low in fat and rich in fruits and vegetables may reduce the risk of certain cancers.”
“Diets low in fat and rich in whole oats and psyllim seed husk can help reduce the risk of heart disease.”

22. Whole Grain - Rich Source of Fiber
Bran – most of the fiber
Germ – much of vitamin and minerals
Endosperm – mostly starch
Refined flour has little bran or germ left = empty calories