1. Nature’s flavor enhancer
LIPIDS
Nature’s flavor enhancer

2. lipids vs carbohydrates - Contain carbon, hydrogen, and oxygen
Do not dissolve in water
Do not provide structure to food products
Fats, oils, shortening, phospholipids, sterols, and cholesterol

3. Structure of lipids 2 basic parts:
Glyceride: molecules that have a glycerol base
Contain 3 hydroxyl groups
Monoglyceride: one fatty acid attached at the side of the hydroxyl group
Diglyceride: two fatty acids attached
Triglyceride: fatty acid joined at each of the three hydroxyl sites
Fatty acid: Organic molecules that consist of a carbon chain with a carboxyl group
Carboxyl group: 1 Carbon atom + 2 Oxygen atoms + 1 hydrogen atom
20 fatty acids = many combinations of triglycerides

4. 3 general types of lipids
triglycerides
phospholipids
sterols
Major type of fat found in food and in bodies
2 fatty acids and phosphorus containing acid attached
Soluble in water
In body: carries food back and forth across cell membranes
In food: helps fats stay in water-based solutions
Ex: mayonnaise
Molecules derived or made from lipids
Cholesterol

5. Categories of lipids
Molecular structure
Physical state

6. 1. Molecular structure Saturated fatty acids
Max number of hydrogen atoms
do not contain double bonds
Ex: butter & coconut oil

7. 1. Molecular structure
Unsaturated fatty acids – some double bonds between carbon atoms in this molecule
Monounsaturated fatty acids – only 1 double bond between 2 carbon atoms
Ex: olive oil, almonds, walnuts, and canola oil
Polyunsaturated fatty acids – 2 or more double bonds in the
carbon chain
ex: safflower, sunflower, and corn oils

8. 2. Physical states of lipids
Fat
oil
Hydrogenated products
Solid at room temperature
Generally saturated fatty acids
More hydrogen atoms
Liquid at room temperature
Generally mono or polyunsaturated
Adding hydrogen atoms to an unsaturated lipid to increase saturation
Makes liquid oil solid
Ex: vegetable shortening

9. Cooking with lipids

10. Role of lipids in cooking
Fats serve as a medium for heat transfer
Tenderize
aerate
Enhance flavor
Lubricate food components
Serves as liquids in emulsions

11. Role of lipids in cooking
Fats serve as a medium for heat transfer
Temperature continues to increase as heat is added, until it reaches the smoke point
Smoke point: The temperature at which fatty acids break apart and produce smoke
Example: deep frying French fries experiment!
Under-heated oil – foods absorb oil and final dish is greasy
Over-heated oil – foods cook too quickly and outside is burnt and inside isnt cooked through
If you see wisps of smoke coming from the edges of the pan, its at its smoke point. Remove from heat – oil is too hot!
Heat pan first, when a drop of water sizzles and evaporates on contact with pan, add oil and it will heat through in a matter of seconds

12. Role of fats in cooking Tenderize
Fat shortens the molecule strands caused by flour
Results in a more tender product
Reason behind “shortening” name
Example: pie crusts & biscuits
Fat coats and separate the flour particles from each other, when cooked – the fat evaporates and leaves flakes within the crust

13. Role of fats in cooking aerate
Fat allows tiny bubbles to form when batters are
beaten (cream fat and sugar)
Example: cookies & cake
Enhance flavor
Fat dissolves and disperses flavor compounds from other ingredients, such as vegetables
So air bubble are incorporated into the batter. Air bubble expand when heat is added and allows the product to rise.

14. Role of fats in cooking Lubricate food components
Makes meat easier to chew
Marbling:
Specks or streaks of fat in muscle tissue
More marbling = more tender
Makes other foods seem to have more moisture
Ex: mayo or butter on sandwiches
Think of a pork chop versus a steak. Pork chop is much chewier!
Adding bread to a piece of toast will make it seem less dry

15. Role of fats in cooking Serves as liquids in emulsions
Mixture that contains a non-polar lipid and a water-based liquid
Water: polar (unequal sharing of electrons)
Polar compounds will combine easily with each other
Lipids: non-polar (equal or balanced sharing of electrons)
Example of non-emulsion: oil and vinegar

16. Lipids & your body

17. Functions of lipids in the body
Help supply energy between meals
Takes longer to digest than carbohydrates and gives a longer feeling of fullness
9 calories per gram
Twice the energy provided by a gram of starch or sugar

18. Functions of lipids in the body
Maintains body temperature
Adipose tissue: tissue the body stores lipids for future needs
Under skin & acts as an insulator holding in body warmth

19. Functions of lipids in the body
Cushion for vital organs
Cell wall production
All cell walls made of lipids and protein
Diets 100% fat free for extended periods are dangerous and should be avoided

20. Functions of lipids in the body
Vitamin transportation
Vitamins A, D, E, & k are fat soluble, so they MUST combine with fat to be transported through the body
Production of hormones & vitamins

21. Functions of lipids in the body
Provide the body with essential fatty acids
Cannot be produced by the body and must come from food
Linoleic acid (an omega-6 fatty acid): corn, cottonseed, and soybean oils; chicken
Linolenic acid (an omega-3 fatty acid): canola oil, soybean oil, walnuts, fish

22. Omega-3 fatty acids possible connection to reduction of heart disease
Research indicates these fatty acids
Help lower triglyceride levels in the blood
Slow growth of plaque in the arteries
Fish that have pink or red flesh are higher in omega-3 fatty acids
Albacore tuna, salmon, lake trout, & sardines
Canola oil, flaxseed, & walnuts become omega-3 fatty acid in the body

23. cholesterol Transported throughout body by lipoproteins
HDL – carries cholesterol from blood back to liver, which processes the cholesterol for elimination from the body
“good” (unsaturated) – olive oil, corn oil, soybean oil
Ldl – carries cholesterol from liver to rest of body
“Bad” (saturated) – coconut & palm oil, butter, bacon, eggs, sour cream, aged cheeses, whole milk
Causes plaque deposits inside arteries
Rigid molecule that helps solidify cell walls
25% of all cell walls
Insoluble in water

24. Dietary recommendations
20-35% of calories should come from fat
8oz or more per week of various fish and seafood
Fat-free diet does not
provide essential fatty acids
Transport fat-soluble nutrients
Protect vital organs
Produce hormones & vitamins

25. Conscious about cholesterol
Use the iPads or byot, to read through the following websites to help you complete the accompanying worksheet
Part 1:
Part 2: cholesterol/in-depth/cholesterol/art
part 3:
Part 4:
**all links are on my website