Chapter 5: The Lipids; Triglycerides, Phospholipids, and Sterols

olestra

a synthetic fat made from sucrose and fatty acids that provides o kcalories per gram also know as sucrose polyester

hydrophobic

a term referring to water fearing or non water soluble substances also know as lipopholic

hydrophilic

a term referring to water loving or water soluble substances

atherosclerosis

a type of artery disease characterized by plaques (accumulations of lipid containing material) on the inner walls of the arteries

glycerol

an alcohol composed of a three carbon chain, which can serve as the backbone for a triglyceride

linolenic aicd

an asssential fatty acid with 18 carbons and three double bonds

trans fatty acids

fatty acids with hydrogens on opposite side of the double bond

essential fatty acids

fatty acis needed by the body but not made by it in amounts sufficient to meet physiological needs

ldl (low density lipoprotein)

the type of lipoprotein derived from very low density lipoporteins as vldl triglycerides are removed and broken down; composed primarily of cholesterol

VLDL (very low density lipids):

the type of lipoprotein derived from very low density lipoproteins and vldl tryglycerides are removed and broken down; composed primarily of cholesterol

hdl (high density lipoproteins)

the type of lipoprotein that transports cholesterol back to the liver from the cells; composed primarily of protein

omega

the last letter of the Greek alphabet used by chemists to refer to the position of the first double bond from the methyl end of a fatty acid

cardiovascular disease

a general term for all diseases of the heart and blood vessels. atherosclerosis is the main cause of cvd. when the arteries that carry blood become blocked the heart suffers damage known as coronary hear disease

choline

a nitrogen containing compound found in foods and made in the body from the amino acids methionine. choline is part of the phospholipid lecithin and the neurotransmitter acetylcholine

omega 6 fatty acid

a poly-unsaturated fatty acid in which the first double bond is six carbons from the methyl end of the carbon chain

omega 3 fatty acid

a polyunsaturated fatty acid in which the first double bond is three carbons away from the methyl end of the carbon chain

oxidation

the process of a substance combining with oxygen; oxidation reactions involve the loss of electrons

eicosanoids

derivatives of 20 carbon fatty acids biologically active compounds that help to regulate blood pressure blood clotting and other body functions. they include prostaglandins, thromboxanes, and leukotrienes

hydrogenation

a chemical process by hydrogens are added to monounsaturated or polyunsaturated fatty acids to reduce the number of double bonds making the fats more saturated and more resistant to oxidation protecting against rancidity. hydrogenation produces

conjugated linoleic acid

a collective term for several fatty acids that have the same chemical formula as linoleic acid (18 carbons and two double bonds) but with different configurations

phospholipid

a compound similar to triglyceride but having a phosphate group (a phosphorus containing salt) and choline (or another nitrogen containing compound) in place of one of the fatty acids

lipids

a family of compounds that includes triglcerides, phospholipids, and sterols. Lipids are characterized by their insolubility in water. (lipids are also include the fat soluble vitamins described in chapter 11.

hormone sensitive lipase

an enzyme inside adipose cells that responds to the body's need for fuel by hydrolyzing triglycerides so that their parts (glycerol and fatty acids) escape into the general circulation and thus become available to other cells for fuel. the signals to which this enzyme responds include epinephrine, and glucagon, which oppose insulin

lipoprotein lipase

an enzyme that hydrolyzes triglycerides passing by in the bloodstream and directs their parts into the cells, where they can be metabolized for energy or reassembled for storage.

linoleic acid

an esential fatty acid with 18 carbons and two double bonds

eicosapentaenoic acid epa

an omega 3 polyunsaturated fatty acid with 20 carbons and five double bonds; present in fish and synthesized in small amounts in the body from linoleic acid

docoshexaenoic acid dha

an omega 3 polyunsaturerated fatty acid with 22 carbons and six double bonds; present in fish and synthesized in small amounts in the body from linoleic acid

arachidonic acid

an omega 6 polyunsaturated fatty acid with 20 carbons and four double bonds; present in small amounts in meat and other animal products and synthesized in the body from linoleic acid

antioxidents

as food additive preservatives that delay or prevent rancidity of fats in foods and other damage to food caused by oxygen

lipoproteins

clusters of lipids associated with proteins that serve as transport vehicles for lipids and blood

sterols

compounds containing a four ring carbon structure with any of a variety of side chains attached

fat replacers

ingredients that replace some or all of the functions of fat and may or may not provide energy

oils

lipids that are liquid at room temperature

fats

lipids that are solid at room temperature

monoglycerides

molecules of glycerol with one fatty acid attached. a molecule of glycerol with two fatty acids attached is a diglyceride.

lecithin

one of the phospholipids. both nature and the food industry use "blank" as an emulsifier to combine water soluble and fat soluble ingredients that do no ordinarily mix such as water and oil

cholesterol

one of the sterols containing a four ring carbon structure with a carbon side chain

blood lipid profile

results of blood tests that reveal a person total cholesterol triglycerides and various lipoproteins

adipose tissue

the body's fat tissue, consists of masses of triglyceride-storing cells

triglycerides

the chief form of fat in the diet and major storage form of fat in the body; composed of a molecule of glycerol with three fatty acids; also called triglycerols

chylomicrons:

the class of lipoproteins that transport lipids from the intestinal cells to the rest of the body

micelles:

tiny spherical complexes of emulsified fat that arise during digestion; most contain bile salts and the products of lipid digestion including ffay acids monoglycerides, and cholesterol.

artificial fats

zero energy fat replacers that are chemically synthesized to mimic the sensory and cooking qualities of naturally occurring fats but are totally or partially resistant to digestion