Foods and Nutrition Midterm (second half)

What are lipids?

organic (carbon-containing) compounds, not soluble in water, but are soluble in organic solvents

What are fats?

lipids that are solid at room temperature (25C or 70F)

What are oils?

lipids that are liquid at room temperature

what do lipids include?

triglycerides, phospholipids, sterolds

how many carbon chains of fatty acids are most common in meats, seafood, and vegetable oils?

14-18

how many carbon chains of fatty acids are most common in fatty fish?

20-24

how many carbon chains of fatty acids would be in the medium-chain fatty acid category?

6-12 (example: coconut oil)

how many carbon chains of fatty acids would be in a short chain?

4 or fewer (example: dairy products)

What does SAFA stand for?

saturated fatty acids

What does MUFA stand for?

Monounsaturated fatty acid

What does PUFA stand for?

Polyunsaturated fatty acid

What does MUFA contain?

1 double bond, but lacks two hydrogens (example: olive oil)

What does PUFA contain?

2 or more double bonds (example: vegetable oil)

what is hydrogenation?

Chemical process of adding hydrogens to monounsaturated/polyunsaturated fatty acids to make the fats more saturated, making them more solid and resistant to oxidation

where are trans-fatty acids usually found?

margarines, baked goods, fast foods

what is the structure of triglycerides?

3 units of fatty acids attached to 1 unit of glycerol

Describe triglycerides.

Chemical structure looks like an “E”; Glycerol molecule connected with three fatty acid “tails” (chains of carbon atoms), Fatty acids may be 4-24 carbons long (always even number), 18 carbons most common in food, Fatty acids can be saturated or unsaturated (saturation refers to hydrogen bonds), Important unsaturated fatty acids include omega-3 and omega-6 fatty acids, the number corresponds to their first point of unsaturation (at carbon 3 or carbon 6) 8-carbon fatty acids that fit the above description are linolenic acid (omega-3) and linoleic (omega-6). Both are essential – aka the body cannot make them itself, it needs to be consumed through diet

what are phospholipids soluble in?

water and fat

what is the function of phospholipids?

to emulsify, key role in cell membranes

what are sterols?

Interconnected rings of C atoms with side chains of C,H,O attached

what’s it called when there’s too much cholestrol in the blood that leads to plaque formation in artery walls?

atherosclerosis

what is bile made up of?

acids, salts, cholestrol, phospholipids, electrolytes, water and bilirubin

where is 98% of fat absorbed through

instestinal villi

what is a chylomicron?

largest lipoprotein, has mostly triglyceride, with little protein (least dense), transports diet-derived lipids from small intestine via lymph system to rest of the body

what does LDL do?

Circulate through body, making their contents available to cells of all tissues, cells use the triglycerides, phospholipids, and cholesterol from LDL for energy

what are the essential fatty acids?

linoleic acid, alpha-linolenic acid, eicosanoids, fatty acid deficiency

What is DRI’s recommended percentage for Sat Fat?

DRI: < 10% of total kcal from SFA

What is WHO'’s recommended percentage for Sat Fat?

WHO: 0 –10% of total calories from SFA

What is DRI'’s recommended percentage for Trans Fat?

as little as possible

What is WHO'’s recommended percentage for Trans Fat?

less than 1% of total kcal from trans fat

What is DRI’s recommended percentage for Linoleic (Omega 6)?

5-10% of total kcal

What is DRI’s recommended percentage for α-linolenic acid (Omega-3)?

0.6 – 1.2% of total kcal

What is WHO'’s recommended percentage for Total Fat?

15-30% of total kcal from fat

What is DRI'’s recommended percentage for Total Fat?

20-35% of total kcal from fat (AMDR)

How many calories yields from 1 gram of fat?

9 calories