6. Monosaccharides
Glucose Fructose Galactose
Mild sweet Sweetest Hardly tastes
flavour sugar sweet
Known as Found in fruits and Rarely found
"blood sugar" honey naturally alone
Essential energy Added to soft
source drinks, cereals
7. Disaccharides
Made up of two monosaccharides
Formed through condensation
Taken apart via electrolysis
Three types: sucrose, lactose, maltose
8. Disaccharides
Sucrose Lactose Maltose
Fructose and Glucose and
2 Glucose units
glucose galactose
Found in table
Found in milk Not abundant
sugar
Produced when
starch breaks
down
11. Glycogen
Limited in meat and not found in plants
Not an essential source of carbohydrates
Glucose is always stored as glycogen
easy release of energy in long chains
12. Starch
Found in plants and stored in plant cells
Created through photosynthesis
Body hydrolyzes plant starch into glucose
13. Fiber
Structural parts of plants
Fibers are not broken down during digestive
process
Two types - soluble and insoluble
14. Fiber
Soluble Insoluble
Easily digested by
Promotes bowel movement
bacteria in colon
Associated with
protection against heart Alleviates constipation
disease and diabetes
Found in grains and
Found in legumes and fruits
vegetables
16. Testing for
Carbohydrates
Benedict's Test for
Reducing Sugars
Iodine Test for Starch
17. Benedict's Test
Used to test for presence of reducing sugars
all monosaccharides
disaccharides: lactose and maltose
Requires use of Benedict's Reagent
prepared from CuSO4, NaOH, tartaric acid
18. Benedict's Test
1. Dissolve food sample in water
2. Add small amount of Benedict's Reagent
3. Heat in water bath from 4 - 10 minutes
4. Positive test indicated by a brick red solution
21. Testing for Sucrose
Sucrose is a non-reactive substance
does not react with Benedict's Reagent
Break down with dilute Hydrochloric Acid before
testing
broken down into fructose and glucose
22. Iodine Test
Used to test for starch
Requires use of Iodine
solution
dissolve iodine in
potassium iodide
23. Iodine Test
1. Add Iodine solution directly to food sample
2. A dark blue-black colour indicates presence of
starch
25. Carbohydrate Digestion
Break down carbohydrate into glucose
able to be absorbed and used by body
Starch - extensive breakdown
Disaccharides - broken down once
Monosaccharides - need not be broken down
26. Carbohydrate Digestion
Occurs throughout digestive system
Begins in mouth
chewing releases saliva
starch broken down by enzymes into
polysaccharides and maltose
27. Digestion in the
Stomach
No enzymes available for starch breakdown
Acid does minor breakdown
Fibers provide feeling of "fullness"
28. Digestion in the
Small Intestine
Primary site of carbohydrate digestion
Pancreatic enzyme reduces carbohydrates into
glucose chains or disaccharides
Specific enzymes are present to fully reduce
disaccharides
29. Digestion in the
Large Intestine
1 to 4 hours for sugars and starches to be fully
digested
Only fibers remain
retain water to soften stool