Chapter 5 Flashcards
The Structures of Sugars: Composed of ___, ____, and ____.
carbon, hydrogen and oxygen
Simple sugars:
- ______
- _____
Monosaccharides
Disaccharides
Sugar Alcohols:
- Sugars with ____ of one corner of their molecule.
- Cause ___ ___ in ___ ___ levels.
- Don’t participate in ____ reactions- lacking ___ ___.
modification corner molecule slow rise blood insulin chemical aldehyde group
Food Lipids: Fat and Oils
- The predominate chemical structure of lipids is the ____.
- Glycerol is a __-carbon molecule containing __ -___ (___) groups.
-Fatty acids are chains of ____ with a ___ at one end and a ___ at the other end.
triglyceride 3 3 -OH (alcohol) carbon carboxyl methyl
Saturated and Unsaturated Fats:
- ____– does not contain any C=C.
- ______– have one or more C=C.
Saturated
unsaturated
The omega naming system names fatty acids by where the __ ___ bond occurs counting from the ___ group ____.
first
double
methyl
backward
The pattern of the double bonds is also important because it determines ___ ___.
When the double bonds occur between every other carbon it is referred to as ____ double bonds.
chemical reactivity
conjugated
When a carbon without a double bond occurs between two sets of double bonds it is called ____.
More ____ and more ____.
interrupted
typical
reactive
Cis and Trans Fats:
- Refers to ___ ___ around the double bond of unsaturated ___.
- When the hydrogen are on the same side it is ___.
- When the hydrogen are on opposite sides it is ___.
geometric configuration
FA
cis
trans
___ is more common in nature, but ___ configuration occurs when vegetable oil is hydrogenated.
Cis
trans
___ ___- The temperature where a solid is converted to a liquid.
Melting Point
Lipids that are ___ at room temperature are referred to as fats and they possess ____ structure.
- The composition of the fat affects its __ ___.
- The more similar the triglycerides in a given fat the ____ the melting range.
- ___ chain fatty acids have higher melting points than ____ chain, ____ higher than ___, ___ higher than ___.
solid crystalline melting point narrower Longer shorter saturated unsaturated trans cis
**___ ____: Characteristic temperature at which fats begin to break down.
- Most fats begin to decompose ___ their boiling point.
- May spontaneously ___ on the stove if their fumes come in contact with flame.
- Depends on initial __ __ ___ content.
Smoke Point
before
ignite
free fatty acid
Flavor Compounds:
- Fats are highly important to ___, both good and bad flavors.
- _____ Oils
- ___ ___ products
flavor
Essential
Lipid degradation
Polar Lipids:
-Represented primarily by ____, these lipids have both ___ and ___ regions (___).
phospholipids
polar
nonpolar
amphiphilic
Pigments: Many of the pigments that provide color to plants and animals are __ ___.
fat soluble
Waxes:
- Waxes are ___ melting point lipids composed of a long chain __ ___ and a long chain ___ ___, esterified to each other.
- They primarily occur in the ___ layer of ___ and provide ___.
high fatty acid fatty alcohol outer plants protection
_____ – splits lipids into higher and lower melting point component parts.
-Can produce a good __ ___ and plastic fat for shortening from same ___ material.
Fractionation
frying oil
starting
_____ – the forced addition of hydrogen to unsaturated lipids.
-This will raise the ___ ___ and increase ____, but produces ___ ___ ___, which may have health disadvantages.
Hydrogenation
melting point
stability
trans fatty acids
_____ – a reaction requiring heat plus the addition of water molecules to separate fatty acids from glycerol.
- Produces an __ ___ referred to as ___ ___, which is caused by the release of short chain fatty acids.
- When all three fatty acids are lost during heating, the glycerol molecule can be further degraded to ___, which is responsible for the __ ___ of oils that are at their ___ point.
Hydrolysis off flavor hydrolytic rancidity acrolein noxious aroma smoke
- _______: This is the rearrangement of fatty acids on the glycerol molecule to create less homogenous triglycerides molecules.
- The primary function of interesterification is to cause __ ___ such as lard to have a ___ texture.
Interesterification
plastic fats
smoother
Oxidation:
-Oxygen reacts at the double bonds of unsaturated fatty acids and causes the production of __ __ compounds that are responsible for “___” odors.
Unsaturated FA react with oxygen to produce ____ and eventually the degradation of the ___ to ___ compounds (__, ___, __, ___).
small organic "rancid" hydroperoxides peroxide volatile ketones, aldehydes, alcohols, acids
Oxidation:
- The reaction sequence can be caused by __, __, __, ___, etc.
- ____ can prevent the reaction by donating hydrogen which basically terminates the reaction.
heat, light, metals, oxygen
Antioxidants
______ - Primarily occurs in heated oils where fatty acids that are cleaved from the glycerol molecules link together to produce polymers.
-Contribute to the ____ of overheated oil and the ____ of foods cooked in overheated oils.
Polymerization
smoking
darkening
____ – also called “creaming the fat” when baking cakes.
- This step incorporates ___ through agitation of a batter which is held in place by the ___ molecule arrangement of the fat.
- Ultimately responsible for the ___, or ___ of many baked products.
Aeration air crystal crumb texture
_____– all food fats contain very small crystals of fat which are composed of the fat’s triglycerides.
Crystallization
Because of differences in the fatty acids that make up the triglycerides, different ____ arrangements (_____) are possible.
- Include the classifications __, __, __-__,
- __-__ (___ __) is the most desirable from a functionality standpoint because they provide a smooth texture.
- __ ___ (__) coarser.
crystalline polymorphism α, β, β-prime B-prime (Beta prime) B crystals (Beta)
Crystallization: More ____ triglycerides result in __ ___.
- Fats are interesterified to reduce the ____ and produce _-____ crystals.
- Also, the more homogeneous the more ____ the melting range.
homogeneous B crystals homogeneity B-prime narrow
Emulsification– ____ are an important component of all food emulsions.
Ex: Cake Batter – __ in ___ emulsion
lipids
Oil in water
Flavor – ____ are believed to have the greatest impact on flavor.
-Their contribution to flavor is due to their inherent ____ properties.
lipids
flavor
Lipids:
Also carry flavor compounds that are lipid soluble such as ____.
-Terpenoids are responsible for __ ___, among many other flavors, which are contained in what is referred to as ___ __.
terpenoids
citrus flavor
essential oils
Heat transfer:
___ can be heated to higher temperature than ___.
Lipids
water
____: Lipids provide a smooth, creamy sensation during the mastication of food.
-Difficult to ___.
Mouthfeel
replace
______- Refers to the physical property of a fat which describes its softness at room temperature.
-Plastic fat will ___ when spread but __ its __ __.
Plasticity
deform
hold
new shape
Plasticity:
- This is due to the ____ nature of ___ lipids.
- ____ crystals have a smoother texture, which can be achieved by proper ____.
-Fats composed mainly of β crystals are less __ and more ___ to the touch.
crystalline solid β-prime tempering plastic grainy
______: Because of the lubrication properties of lipids, they also promote _____ of foods that contain them.
- Meat that has higher fat content (___) is more ___ than meat that has __ ___ __.
- In baked goods, ___ interferes with ___ formation.
Tenderization tenderization marbling tender less intramuscular fat lipid gluten
Food Proteins:
- Proteins are polymers of __ __.
- Called ____ because the bond between __ __ is the ___ bond.
-Connects the ____ group of one ___ acid to the ___ acid group of another ___ acid.
amino acids polypeptides amino acids peptide amino amino carboxylic amino
Amino acids all have an ___ group and a ____ group along with a ___ group.
-Functional group dictates classification as __, ___, ___, ___, or ____ containing amino acids.
amino
carboxylic
functional
neutral, basic, acidic, aromatic or sulfur
Proteins exist as either:
- ______: Contain only amino acids
- ______: Combined with other nonprotein substances.
Nonconjugated
conjugated
