Chapter Five Flashcards
What is a lipid?
A group of organic molecules, most of which do not dissolve in water. They include fatty acids, triglycerides, phospholipids, and sterols.
What do lipids contribute to food? (3)
They contribute to the texture, flavour, and aroma.
What is the AMDR recommendation for fat?
20-35% of kcals from fat.
True or False: Soluble Fibre can lower total (and unhealthy) LDL cholesterol levels.
True. The soluble fibre psyllium can also lower total and LDL cholesterol levels without lowering HDL levels.
True or False: Flaxseed can lower LDL cholesterol, but also lowers HDL.
False, Flaxseed can lower LDL without lowering HDL.
Does Soy Protein have an affect on HDL levels?
While lowering LDL, it can have no effect or raise HDL levels.
Plant Sterols and Stanols resemble what and how do they affect blood cholesterol levels?
They resemble cholesterol chemically, making it difficult for the digestive system to tell them apart and causing cholesterol absorption to lower.
What are Triglycerides?
The major form of lipid in food and in the body, they consist of three fatty acids attached to a glycerol molecule. The fatty acids determine the physical properties and health effects of the triglyceride.
What are Fatty Acids?
Organic molecules made up of a chain of carbons linked to hydrogen atoms with an acid group at one end.
What are Phospholipids?
Types of lipids containing phosphorous, the most common type are phosphoglycerides, which are composed to two fatty acids and a phosphate group attached to a glycerol molecule.
What are Sterols?
Types of lipids with a structure composed of chemical rings.
What acid group is at the end of the fatty acid chain?
COOH.
What is the CH3 end of a fatty acid called?
The omega or methyl end.
What are short chain fatty acids?
Fatty acids with 4-7 carbons, they remain liquid at colder temperatures.
What are medium length fatty acids?
Range from 8-12 carbons and solidify in the fridge but become liquid at room temperature.
What are long chain fatty acids?
Greater than 12 carbons, are usually solid at room temperature and have melting points of 50 - 70 degrees Celsius.
Define Saturated Fatty Acid
A fatty acid in which all the carbon are bound to as many hydrogens as possible, with no carbon double bonds.
What are Tropical Oils?
A term used in the popular press to refer to the saturated oils (coconut, palm, and palm kernel oil) that are derived from plants that grow in tropical regions. They are more resistant to rancidity and have longer shelf lives.
What is the carbon description of palmitic acid?
16:0
What is the carbon description of stearic acid?
18:0
What are Unsaturated Fats?
Fatty acids that contain carbons not saturated with hydrogens. They melt at cooler temperatures than their saturated counterparts.
What is a Monounsaturated Fatty Acid?
A fatty acid that contains 1 carbon-carbon double bond. The most popular kind is oleic acid, found in olive and canola oils.
What is a Polyunsaturated Fatty Acid?
A fatty acid containing two or more carbon-carbon double bonds. The most common kind is linoleic acid, found in corn, safflower, and soybean oils.
What is an omega-3 Fatty Acid?
A fatty acid containing a double bond between the third and fourth carbon from the omega end.
What are three examples of omega-3 fatty acids?
1 . alpha-linolenic acid (vegetable oils)2. eicosapentaenoic acid (EPA) (fish oils)3. docosahexaenoic acid (DHA) (fish oils)
What are omega-6 Fatty Acids?
A fatty acid containing the carbon-carbon bond between the sixth and the seventh carbon from the omega end.
What are two examples of omega-6 fatty acids?
- Linoleic acid (con and safflower oil)2. Arachidonic acid (meat and fish)
What are Trans Fatty Acids?
An unsaturated fatty acid in which the hydrogen atoms are in opposite sides of the double bond. They have higher melting points than their cis counterparts.
What are Cis Fatty Acids?
An unsaturated fatty acid with the hydrogen atoms are on the same side of the double bonds, they are more common in nature than trans fatty acids.
What is Hydrogenation?
The process whereby hydrogen atoms are added to the carbon-carbon double bonds of unsaturated fatty acids, making them more saturated. Hydrogenation bubbles hydrogen gas into liquid oil. The resulting (more saturated) fat has increased stability against rancidity and higher melting points, however only some of the bonds will become saturated and making the resulting product have more trans bonds than before.
What happens to the body when trans fats are consumed in the diet?
It raises blood cholesterol levels and increases the risk of heart attacks.