Chapter 10 Lipids
how do phospholipids play important role in our body and food products?
(body) help carry fats back and forth across cell membranes into water-based fluids (foods) help fats stay mixed in water-based solutions (help keep foods like mayo from separating)
name the 4 fxs of lipids in body
1) source of energy ( 9 calroies) 2) cell production - cell walls are composed of fat/ proteins 3) temp regulation 4) transports vitamines (A,D,E,K)
oleic acid , # , and used in what productions?
18:1 and used in margarine production
ppl who need to lower triglycerides ?
2-4 grams of EPA and DHA
how many fatty acids are there?
20
fatty acid and a glycerol forms an _____ bond
ester
Fats are denser and require more energy to liquefy: which has higher melting points? fats or oils
fats
lipids solid at room temperature are commonly called ____
fats
which have more hydrogens? fats or oils?
fats
organic molecules that consists of a carbon chain with a carboxyl group at one end
fatty acid
ppl w/o CHD what should they eat?
fatty fish (x2) a week and consume oils rich in alpha-linolenic acid (flaxseed, canola, walnuts)
why will a triglyceride not dissolve in water?
it has two ends that are nonpolar (neutral in nature)
corn, cottonseed, soybean oil: linoleic or linolenic
linoleic
which are the essential fatty acids?
linoleic & linolenic
18:2 is which fatty acid
linoleic poly
canola oil, soybean, walnuts, fish: linoleic or linolenic
linolenic
which is essential for growth and development? linoleic or linolenic?
linolenic acid
18:3 is which fatty acid
linolenic poly
describe how lipids are different than carbohydrates
lipids have C,H, O but are not polymers, do not provide structure to foods and can't be dissolved in h20
double bonds in fatty acid ___ temperature at which a lipid
lower
explain how an emulsifer works in mayo
mayo has oil and water , the emulsifier keeps them mixed. there is a "hydrophoilic end and hydrophobic end"
lipids are grouped according to ___, ___ and ___
molecular structure ( mono,sat, poly , physical state, dietary sources
what are the categories of lipids?
molecular structure, dietary structure , physical state
has a glycerol and 1 FA
monoglyceride
canola, olive , lard, soybean
monosaturated
fatty acid that have one double bond in the carbon chain
monounsaturated
olive oil, almonds, walnuts and canola examples of
monounsaturated
14:0 is which fatty acid
myristic sat
what does omega 3 FA do to our blood?
natural blood thinners , reduicng the stickiness ( they improve blood flow and make red blood cells more flexible so they can pass through tiny blood vessels more easily (reduce stroke and blood clots
body of triglyceride are ____, but the COOH end on the FA are (slightly positive) and OH groups on glycerol are slightly ( negative)
non-polar
fatty acid are ____ or neutral in nature
nonpolar
what are the type of emulsions?
oil-in -water (small oil that are dispersed in water) water-in-oil has small droplets of water that are dispersed in an oil.
lipids liquid at room tempeature
oils
hydrogenated oils allow what?
oils to be solid at room temperautre
18:1 is which fatty acid
oleic unsaturated ( mono)
starts when lipids are exposed to oxygen..
oxidiation
16:0 is which fatty acid
palmitic sat
why are mono and diglycerides important in food industry?
partially soluble in water because of their hydroxyl group-- they are often added to processed foods to keep mixtures of water ann fats stable
2 fatty acids are soluble in fat & which acid is soluble in water?
phospholipid
2nd basic type of lipid is ____ it has a glycerol base with fatty acids & phosphorus acid attached
phospholipid
this lipid is allowed to mix with both water-based and fat based substances
phospholipid
fatty acids and glycerol are __ molecules
polar
fatty acids and glycerol are non polar or polar?
polar
fatty acids and glycerol are ___ molecules
polar molecules
fatty acids that have 2 or more double bonds in carbon chain
polyunsaturated
safflower, sunflower and corn oils are all examples of
polyunsaturated
safflower, sunflower, cottonseed, chicken fat
polyunsaturated
the bend in double bond makes it difficult for the molecules to pack together tightly. which fatty acid?
polyunsaturated
which liquify and what is the characteristic due to ? (sat, mono or poly?)
polyunsaturated dut to bent shape of chain and lower number of H atoms
in high fat foods when exposed to oxygen they are more likely to become?
rancid
cholesterol, vit D , steroid hormones are familar ____
sterol
is produced by the liver & helps organize cell membrane
sterol
how is ALA different from DHA and EPA
body has enzymes that can convert ALA -> EPA
which are the long chains of omega 3 fatty acids?
...
ppl w/ CHD should have what?
1 gram of EPA and DHA a day
draw glycerol molecule
3 hydroxyl groups
is a precursor to EPA and DHA
ALA
is from flaxseed, walnut, soybean, canola : which omega 3 fatty acid?
ALA (18:3)
omega 3 that is found in dark green leafy veggies, flaxseed oils
ALA linolenic acid
order for omega 3 synthesis?
ALA->EPA->DHA
22:6 which omega 3 FA?
DHA
is in fish and recently obtained from micro algae: which omego 3 fatty acid?
DHA (22:6)
essential can't be ____ by human body BUT are ___ for normal metabolism
DHA and EPAcan't and vital
20:5 is which omega -3
EPA
is an essentail FA from oily fish; anchovies, sardines, salmon
EPA (20:5)
12:0 which fatty acid?
Lauric (saturated, palm & coconut oil)
18:2 which fatty acid?
Linoleic ( polyunsaturated) (corn, cottonseed, olives,peanuts, sesame seeds, sunflowers)
18:3 which fatty acid?
Linolenic ( polyunsaturated ) (soybeans & wheat germ)
category organic compound that are insoluble in water
Lipids
do not provide structure to food products and can't be dissolved in water
Lipids
also come fats, oils, shortening, phospholipids, sterols, cholesterol
Lipids are called
18:1 which fatty acid?
Oleic ( monounsaturated) (cottonseed, peanuts, olives, sesame seeds,sunflowers,canola oil, almonds, walnuts)
the shorter C chains of FA are more ___
RANCiD
18:0 which fatty acid?
Stearic (saturated, milk & beef)
lecithin is what?
an emulsifier that is commonly used in foods it is in eggs & oils seeds (it is a mixture of of diglycerides , stearic, palmitic and oleic )
what happens during dehydration synthesis?
an ester bond forms
benefits of emulsifers
appearance, maintain quality & freshness
20:4 is which fatty acid
arachidonic poly
in oxidation where does O2 binds with lipid molecules?
at sites of double bonds
omega 3 are beneficial in what disorders/diseases?
autoimmune, inflammatory and heart
w.o sufficient amount of omega -3 what will happen?
body will use saturated fat to construct cell membranesand resulting in cell membranes to be less elastic ( this is bad on the heart making it harder to return to a resting state)
low levels of DHA cause reduction on what?
brain serotonin levels and have been associated with Alzheimers , depression among other diseases and some evidence that DHA suppl. may be effective in combaing diseases.
foods that contain emulsifiers
bread, cakes, cereals, ice cream, caramels , biscuits
in hydrogenated oils what do the double bonds in FA do?
break, and pick up extra H--> become more saturated
what is the processe of hydrogenated oils?
bubbling H through liquid oils in presence of catalyst
what are examples of mono and diglycerides that are added to foods?
butter and margarine
easiest way to categorize lipids is
by physical state at room temperature
which group will react with hydroxyl group of glycerol?
carboxyl group
how do trans fatty acids workd?
chemical structure of unsaturated fatty acids after partial hydro turns them into trans-fatty acids
hydrolzed triglycerides does what?
deterioration, hydrolysis large molecules broken into smaller parts by addition of h20
has a glycerol and 2 FA
diglyceride
why are polyunsaturated FA become liquid at lower temps?
due to bent shape and lower # of hydrogens
butter and margarines are used as ____
emulsifiers (mono and di)
base or core of lipid is glycerol
glycerol
different FA attach to ___ , which will result in diff. characteristics to the triglyceride variations in cooking behavior , shelf like and nutritional value
glycerol base
how to name unsaturated fatty acids?
indicate the position of the first double bond counting from the opposite end from the carboxyl group
coconut, palm kernel, beef fat, palm oil
saturated
fatty acids have max number of H atoms
saturated
12:0 is which fatty acid
saturated: lauric
FA in phospholipds are soluble or not soluble in fat?
soluble
18:0 is which fatty acid
stearic acid
3rd type of lipid is complicated derived or made from lipids
sterol
why are mono and di glycerides partially soluble?
they have OH groups , FA make the soluble in fat
how do OMEGA 3 FA play a role in membrane lipids?
they play a role as structural membrane lipids, particulary in nerve tissue and retina and recursors to eicosanoids ( highly fxtionally for a range of fx in cells and tissues )
most lipids in foods and in the body are
triglycerides
mono, di , phospholipids can act as an emulsifer: true or false?
true
what is the greatest effect on the characteristic of lipid?
type of FA
fatty acid doesn't contain all H atoms
unsaturated
which are more susceptible to oxidate? sat or unsat
unsaturated