1-lipid Flashcards
difference btw fat and oil?
different in melting point: fat has high melting point while oil has low MP and is liquid in room T.
Is wax a fat?
No, wax is FA esterified with an alcohol.
which category does jojoba oil and bee’s wax belong to?
Wax
Liquid or solid? Jojoba oil and bee’s wax?
jojoba oil: liquid at room T
Bee’s wax: solid wax
what is application use for wax for food use?
cheese—sealing agent
apple—–polishing agent
How does wax being used in the market？
Cosmetics (monounsaturate long chain FA)
in FOOD: low-calorie food ingredient
Which category does cholesterol ester belong to?
Wax.
FA esterified to a complex alcohol
Give an example of FA esterified to a complex alcohol?
VA/retinol
cholesterol ester
Is wax biologically active?
yes
what is compound lipid?
simple lipid conjugated with non-lipid molecule.
Give examples of compound lipids?
phospholipid, sphingolpid/ glycolipid, lipoprotein.
How is phospholipid differ from triacylglyceral?
TAG: glycerol attached to 3 FA
Phospholipid: glycerol attached to 2 FA + 1 phosphate
What is phosphoric acid?
phosphate group attached to the glycerol backbone
What is a phosphatidic acid?
is the base structure of non-lipid moiety
when X=OH.
X=nitrogenous base when it is a phospholipid.
what is the proportion of phospholipid comprised in the lipid material that found in food system?
5%
Is phospholipid amphipathic?
Yes. both hydrophobic and hydrophilic
what property does phospholipid has?
emulsifying property / emulsifier
Classes of phospholipid?
- lecithin (phosphatidyl choline)
- cephalin (phosphatidyl ethanolamine)
- phosphatidyl inositol
- phosphatidyl serine
which group does cardiolipin belong to? Food sourse?
diphosphatidyl glycerol.
found in beef heart
where does glycolipid found?
In membrane lipid of plants and animals
Give an example of food source of lipoprotein?
Egg
Is HDL good for the body？Why?
yes, it accounts for 1/3 all blood-circulating chol and serve as protective mechanism for heart disease by carrying away chol from vessel walls and plaque to the liver for disposal.
Is LDL neede in the body? WHY?
Yes, because it transport substances vital to cell function and development.
why LDL bad for body?
when LDL is in excess in the blood, it can change its structure from body stress. when it accumulates in the blood vessel walls, they can lead to blockage in artery / unstable plaque build up which is prone to rupture and formation of blood clots.
what is derived lipid?
Derived from simple/ compound class.
Class of derived lipid?
Fatty acid, fatty alcohol, hydrocarbons (ex. oxygenated derivatives)
how does short chain fatty acid important in the food system?
It can be used as flavor compounds.
Can long chain free fatty acid be used as flavor compound? What can it be used as?
no.
- it can be used in the presence of mineral salts (soapy flavor)
- it can used for edible oil by lowering the smoke point for frying
how can short chain alcohol be used? (derived lipid)
Contribute to flavor
give an example of unsaturated hydrocarbon?
terpene (built from isoprene unit)
what is the main component of essential oil?
terpene (monoterpene + sesquiterpene)
Use of lipid?
serve as fuel; emulsifier; give creamy mouthfeel; solubilize many taste and aroma constituent of food; give desired texture;
what class of lipid is of majority of the food system?
fats (95-96%) + phospholipid
when a scientist refer to LIPIDS, what compound does he want to mention?
Triglyceride.
