Module 2 Flashcards
Lipids
Include fat and other substances that are dissolvable in organic substances (ethanol)
What are some high fat foods?
Vegetables:
- Avocado
- Coconut
- French fries
Milk and alternatives:
- Cheese
- Ice cream
- Regular milk
Grains:
- Doughnut
- Muffins
Meat and alternatives:
- Salmon
- Bacon
- Ground beef
Other:
- Butter
- Margarine
- Oil
- Potato chips
- Fudge
Are potatoes a high-fat food?
Only when you deep fry them (depends how you prepare them)
Triglyceride
Over 98% of fat is in this form that we eat
- structure dictates health or health risk
What are the two important aspects of fatty acids?
- chain length (how long or short)
- degree of saturation (as full as it can be of hydrogen)
What are the different lengths of fatty acid chains?
Short chain: 2-4 carbons
Medium: 6-12 carbons
Long (majority of what we’re eating: 14-122 carbons
What makes a fatty acid saturated?
In the carbon chain the carbons have to be attached to 4 things (not double bonds, as full of hydrogen as it can be)
Ex palmitic acid 16:0
Monounsaturated fatty acid (MUFA)
- only one double bonded carbon
Ex. oleic acid 18:1n-9 (omega-9)
Polyunsaturated fatty acids (PUFA):
two or more double bonded carbons
- linoleic acid 18:2n-6 (omega-6)
- alpha-linolenic acid 18:3n-3 (omega 3)
What are the two fish oils?
These are highly unsaturated
- Eicosapentaenoic acid (EPA) 20:5n-3 (reduces heart rate)
- Docosahexaenoic acid (DHA) 22:6n-3 (important for brain and eyes)
How can you tell if something is a unsaturated or saturated fatty acid?
- solids are going to be saturated fats since there’s less double bonds (butter)
- Unsaturated is going to be in a liquid state since it has many kinks due to the double bonds
- coconut oil has highest amounts of saturates
Why are fats and oils that have more omega-3 fats worse for cooking with?
- since it as a lot of double bonds it is more susceptible to oxidation and worse for health
- try to store these in tight containers, dark places
- monounsaturated fats are better for cooking with
Why are the polyunsaturated essential?
deficiency of fatty acids could cause:
- scaly dermatitis (inflammation of skin
- excess loss of water through skin
- impaired growth
How does fat play a role in our diet?
- Important source of energy (kcal)
- Provides essential fatty acids (linoleic and linolenic)
- brings along fat soluble vitamins (ADEK) to absorb it
- Palatability (mouth feel and taste) - allows for taste and aroma of foods
How does fat play a role in our body?
- Insulation - helps keep body warm
- Protection - protects skeleton and vital organs from falls
- Energy reserve - store kcal in adipose (fat) cells (reduce levels only by oxidizing/burning fat)
- Precursor for other biomolecules in body:
- fatty acids make eicosanoids (biological messengers) and phospholipids for cell membrane
- cholesterol makes bile acids for steroid hormones
Hydrogenation
Manufacturing/food processing practice
What is the purpose of hydrogenation?
- Transform an oil (liquid fat) into harder fat (margarine)
- purpose for spreadability
- good for use in baking (vegetable oil, shortening) - To enhance shelf life of processed foods (will not oxidize)
Trans fatty acids (TFA)
Category of fatty acids produced during hydrogenation
What’s the difference between naturally-occuring fatty acids and trans fatty acids structurally?
Naturally-occuring:
- have cis double bonds (kinks)
- more kinks makes the fat more liquidy
Hydrogenation produced fats:
- turns the cis double bonds into double linear trans bonds (not kinks)
- makes the fat solid
- similar structure to saturated fatty acids
Food sources of Trans Fatty acis:
Processed foods containing:
1. Margarine
2. Hydrogenated/partially hydrogenated vegetable oil
3. Vegetable oil/shortening
Examples of food that have trans fats:
- Margarine (want to purchase non-hydrogenated)
- Peanut butter
- deep fried foods
- pastry or batter (fish sticks, chicken nuggets)
- most cookies and crackers
Where are we getting most of our trans fats
- mostly from baked foods
- also fast food
What does trans fats contribute to?
coronary heart disease
What are the 3 processes after consuming fats?
Digestion: an enzymatic process - breakdown of whatever we’re eating to the smallest absorbable units
Absorption: take smallest units across absorptive surface of GIT into vascular (blood) or lymphatic system
Metabolism: various pathways nutrients take following digestion and absorption
