Week5-C1 Flashcards
What is the common factor between all lipids?
Their insolubility in water.
What are the 3 types of lipids found in food and in the human body?
1-triglycerides
2-phosopholipids
3-sterols
The ____ are the most abbondant type of lipids found in the food, and most specifically the ___
Glycerides category
triglycerides
Complete : The _____ group of a fatty acid will readily react with the ____ group of glycerol producing a lipid (MG, DG or TG) and one molecule of water
carboxyl
hydroxyl
The fatty acid chains ranges from ___ carbons to ___ carbons
4 to 28 carbons
When forming a triglycerides you need ___ molecules of H20
3
The oxygen from the ____ group of the ___and H from carboxyl group and from the hydroxyl group
carboxyl
FA
Glyceride are considerer to be polar or non-polar?
it depends on the number of FA attached to the glycerol. If 3 are attaches, they are non-polar but if they have less then 3 attached they are partially polar because of the hydroxyl group of the glycerol (partially soluble)
Monounsaturated fatty acids have __ double bond and are found in ___, ___ (oil) and in ___ and ___ (nuts)
one
olive and canola oils, almonds, and walnuts
Omega-3 (ω3) and omega-6 (ω6) fatty acids are ___
fatty acids.
polyunsaturated
ω3 and ω6 designate the position of the 1st double bond when the
fatty acid chain is numbered from the ____ end.
methyl
What are the two geometric isomers? what is the most common one?
cis and trans and cis is the most common one
What is the major fatty acid in olive oil?
Oleic acid (cis-monounsaturated).
What is the trans isomer of the major FA in olive oil?
Elaidic acid
How do you characterize the fatty acids? (technique)
Fats and oils are often characterized by hydrolyzing all the ester
bonds with a strong base (to liberate the fatty acids from the glycerol
backbone) and then analyzing the composition of the resulting mixture
of fatty acids.
What commodity doesn’t contain a free fatty acid content below 1%?
Olive oil
What is the most important physical property of FA?
the melting temperature.
The melting point of FA :
- Increase with ____ chain length
- Decreases with ____ number of cis doubles bonds
- _____ with isomerization of cis to trans
increase
increase
increase
Why does most of plant based oil are liquid at room temperature?
because they contain a lot of unsaturated fatty acids in the cis configuration
What manipulation can you do to FA to increase the solidity at room temperature
You can saturate the FA (catalytic hydrogenation)
True or False : The solidity at room temperautre decrease with the number of double bonds
true
Complete : Lipids from plant sources tend to be more ____ and are ___.
unsaturated
oil
Complete : Lipids from animal sources tend to be more ____ and are ___
saturated
fat
Complete : lipids from fish sources tend to be ____ oils
highly polyunsaturated
Complete : an increase in cis double bond ____ the melting point
decrease
What happens when to the double bond when you subject fatty acids to catalytic hydrogenation
The double bond either disappear or change configuration from cis to trans.
What is the alternative process to catalytic hydrogenation?
Interestierification
What is interesterification?
A process by witch you change the positions of the FA on the glycerol, changing the properties.
What are the advantages of the hydrogenation ? (3)
- Longer SL
- Greater stability and lower production cost
- Faster dissolving and setting propreties in chocolate production
What is the name of the smallest fatty acid
Butyric acid.
Why does tropical oils have a low melting point even thought they are saturated FA
Because they have a short chain length.
