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1
Q

The Structures of Sugars: Composed of ___, ____, and ____.

A

carbon, hydrogen and oxygen

2
Q

Simple sugars:

  • ______
  • _____
A

Monosaccharides

Disaccharides

3
Q

Sugar Alcohols:

  • Sugars with ____ of one corner of their molecule.
  • Cause ___ ___ in ___ ___ levels.
  • Don’t participate in ____ reactions- lacking ___ ___.
A
modification
corner
molecule
slow
rise
blood insulin
chemical
aldehyde group
4
Q

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.

A
triglyceride
3
3 -OH (alcohol)
carbon
carboxyl 
methyl
5
Q

Saturated and Unsaturated Fats:

  • ____– does not contain any C=C.
  • ______– have one or more C=C.
A

Saturated

unsaturated

6
Q

The omega naming system names fatty acids by where the __ ___ bond occurs counting from the ___ group ____.

A

first
double
methyl
backward

7
Q

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.

A

chemical reactivity

conjugated

8
Q

When a carbon without a double bond occurs between two sets of double bonds it is called ____.
More ____ and more ____.

A

interrupted
typical
reactive

9
Q

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 ___.
A

geometric configuration
FA
cis
trans

10
Q

___ is more common in nature, but ___ configuration occurs when vegetable oil is hydrogenated.

A

Cis

trans

11
Q

___ ___- The temperature where a solid is converted to a liquid.

A

Melting Point

12
Q

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 ___.
A
solid
crystalline
melting point
narrower
Longer
shorter
saturated
unsaturated
trans
cis
13
Q

**___ ____: 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.
A

Smoke Point
before
ignite
free fatty acid

14
Q

Flavor Compounds:

  • Fats are highly important to ___, both good and bad flavors.
    • _____ Oils
    • ___ ___ products
A

flavor
Essential
Lipid degradation

15
Q

Polar Lipids:

-Represented primarily by ____, these lipids have both ___ and ___ regions (___).

A

phospholipids
polar
nonpolar
amphiphilic

16
Q

Pigments: Many of the pigments that provide color to plants and animals are __ ___.

A

fat soluble

17
Q

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 ___.
A
high
fatty acid
fatty alcohol 
outer
plants
protection
18
Q

_____ – splits lipids into higher and lower melting point component parts.

-Can produce a good __ ___ and plastic fat for shortening from same ___ material.

A

Fractionation
frying oil
starting

19
Q

_____ – the forced addition of hydrogen to unsaturated lipids.

-This will raise the ___ ___ and increase ____, but produces ___ ___ ___, which may have health disadvantages.

A

Hydrogenation
melting point
stability
trans fatty acids

20
Q

_____ – 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.
A
Hydrolysis
off flavor
hydrolytic rancidity
acrolein
noxious aroma
smoke
21
Q
  • _______: 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.
A

Interesterification
plastic fats
smoother

22
Q

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 (__, ___, __, ___).

A
small organic
"rancid"
hydroperoxides
peroxide 
volatile 
ketones, aldehydes, alcohols, acids
23
Q

Oxidation:

  • The reaction sequence can be caused by __, __, __, ___, etc.
  • ____ can prevent the reaction by donating hydrogen which basically terminates the reaction.
A

heat, light, metals, oxygen

Antioxidants

24
Q

______ - 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.

A

Polymerization
smoking
darkening

25
Q

____ – 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.
A
Aeration
air
crystal 
crumb
texture
26
Q

_____– all food fats contain very small crystals of fat which are composed of the fat’s triglycerides.

A

Crystallization

27
Q

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.
A
crystalline
polymorphism
α, β, β-prime
B-prime (Beta prime)
B crystals (Beta)
28
Q

Crystallization: More ____ triglycerides result in __ ___.

  • Fats are interesterified to reduce the ____ and produce _-____ crystals.
  • Also, the more homogeneous the more ____ the melting range.
A
homogeneous
B crystals 
homogeneity
B-prime 
narrow
29
Q

Emulsification– ____ are an important component of all food emulsions.

Ex: Cake Batter – __ in ___ emulsion

A

lipids

Oil in water

30
Q

Flavor – ____ are believed to have the greatest impact on flavor.

-Their contribution to flavor is due to their inherent ____ properties.

A

lipids

flavor

31
Q

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 ___ __.

A

terpenoids
citrus flavor
essential oils

32
Q

Heat transfer:

___ can be heated to higher temperature than ___.

A

Lipids

water

33
Q

____: Lipids provide a smooth, creamy sensation during the mastication of food.

-Difficult to ___.

A

Mouthfeel

replace

34
Q

______- Refers to the physical property of a fat which describes its softness at room temperature.

-Plastic fat will ___ when spread but __ its __ __.

A

Plasticity
deform
hold
new shape

35
Q

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.

A
crystalline
solid
β-prime
tempering
plastic
grainy
36
Q

______: 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.
A
Tenderization
tenderization
marbling
tender
less intramuscular fat
lipid
gluten
37
Q

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.

A
amino acids
polypeptides
amino acids
peptide
amino 
amino 
carboxylic 
amino
38
Q

Amino acids all have an ___ group and a ____ group along with a ___ group.

-Functional group dictates classification as __, ___, ___, ___, or ____ containing amino acids.

A

amino
carboxylic
functional
neutral, basic, acidic, aromatic or sulfur

39
Q

Proteins exist as either:

  • ______: Contain only amino acids
  • ______: Combined with other nonprotein substances.
A

Nonconjugated

conjugated

40
Q
Conjugated: 
Examples: \_\_\_\_: \_\_\_, e.g. \_\_ \_\_\_
Lipid: 
Metals: metalloproteins, e.g. hemoglobin
Phosphorus: phosphoproteins,
A

carbs, glycoproteins

egg white

41
Q
There are \_\_ levels of protein structure:
1. 
2. 
3.
4.
A
4
primary
secondary
tertiary
quaternary
42
Q

_____ is the linear arrangement of amino acids.

Example: ____ (shorthand for primary structure)

A

Primary

N-C-C-N-C-C

43
Q

_____ is the structural arrangement of the amino acids such as __-__, __-___ sheet.

A

Secondary
alpha-helix
beta-pleated

44
Q

_____ is the overall three dimensional structure.

A

tertiary

45
Q

_____ is the arrangement of more than one peptide chain within a single protein molecule.

A

Quaternary

46
Q

_____ – preventing a pH change by undergoing an ionization reaction.

_____ – can behave as both acids and bases.

  • ___ groups can act as acids.
  • ___ groups can act as bases .
A

Buffering
Amphoteric
Carboxyl
amino

47
Q

_____ can serve as buffers (maintain pH) because of this and can be either ___ or ____ depending on the pH of the food.

A

Proteins
acidic
basic

48
Q

_______- the loss of three dimensional structure without breaking the primary structure.

  • When proteins denature they lose ____ properties.
  • Denaturation occurs due to __, ___ ___.
  • __ __ __ may cause the protein to coagulate, which is more ___ than mere denaturation.
A
Denaturation
functional
heat, acid, agitation
Excessive energy input
severe
49
Q

Enzymes – all enzymes are ____.

Many enzymes impact ___ ___, both naturally occurring & industrial enzymes that are purposefully used in food processing.

Natural enzymes that influence food quality include ____ in meat and ____ in fruits.

-Enzyme activity is affected by ____ (optimum is generally between __-__degreesC), __ (optimum generally between __-__) and __ __.

A
proteins
food quality
proteases
phenoloxidases
temperature
30-40
ph
water activity
50
Q

Emulsification – proteins can stabilize emusions by acting at the __-__ interface.

A

oil-water

51
Q

Fat Reduction – proteins are often used as __ __.

A

fat replacers

52
Q

Monosaccharides:

-Are the basic ___ ___ around which ___ carbohydrate units are built.

-Nomenclature is based on the number of ___.
-____ – 3 carbons.
-____ – 5 carbons.
-___ – 6 carbons.
__, ___, ___ – C6H12O6

A
building blocks
larger 
carbons
trioses
pentoses
hexoses
glucose, fructose, galactose
53
Q

Monosaccharides:

-Structural features, which are dependent on the location of ____ groups, have an influence on ____ properties.

-Glucose has a __ membered ring (___)
Fructose has a __ membered ring (___)

-This difference is partially responsible for the fact that fructose is ___ and more ___ than glucose.

A
functional
functional 
6
aldose
5
ketose
sweeter
soluble
54
Q

Disaccharides:

-___ monosaccharides bonded together by a ___ bond.

A

two

glycosidic

55
Q

The three most common disaccharides in food are:

  1. _____ (____ + ____) - common table sugar
  2. ____ (___ + ___) - milk sugar
  3. _____ (___ + ____) - common breakdown product from starch.
A
sucrose
glucose
fructose
lactose
glucose galactose
maltose
glucose 
glucose
56
Q

Two important functional groups of Sugars:

  1. ___ (-___) group– important for solubility & sweetness.
  2. ___ (___) group– important for reducing activity and Maillard browning for color/flavor development.
A

Alcohol -OH

Carbonyl (-C=O)

57
Q

Sugar functional groups:

These functional groups are either a ___ (on the ___ of the molecule) or an ____ (on the ___ of the molecule).

A

ketone
interior
aldehyde
end

58
Q

Reducing sugars- contain a ____ group (___ or _____).

-All ______ are reducing sugars.

A

carbonyl
(aldehyde or ketone)
monosaccharides

59
Q

There are two important browning reactions that occur in sugar:

  1. _____ reactions
  2. _______
    Both are categorized as ______.
A

Maillard
Caramelization
nonenzymatic

60
Q

____ _____ – a complex series of reactions that requires a reducing sugar and amino acids in foods.

A

Maillard reaction

61
Q

____ ____ – the browning of foods as a result of the Maillard reaction.

-Intermediate products: _____, which tend to have pleasant aromas and flavor.

  • End products: brown pigments called ____.
    • _____ and result in ____ of food.
A
Maillard browning
pyrazines
melanoidins
Irreversible
darkening
62
Q

The Maillard reaction is responsible for both ___ and ____ quality attributes, depending on the product.

A

positive and negative

63
Q

The Maillard reaction takes place at relatively __ temperatures and can be accelerated by ___ molecular weight sugars, low __ __ (<15%) and in the pH range of __-__.

A

low
lower
moisture content
5-8

64
Q

Caramelization – takes place at ___ temperature (200 C)

  • Due to the _____ of the sugar molecule.
  • ___ ___ refers to a brown coloring used in the food industry.
  • Caramel refers to sauces or candies made from carbohydrates that have been allowed to ____.
A

high
dehydration
Caramel coloring
caramelize

65
Q

Crystallization:

  • ___ ___ can exist as syrups or the crystallized state.
  • Crystallization– implies organized __-_ arrays of unit cells into solid form.
  • In candy manufacture, control of the ____ process is highly critical to the ultimate quality of the candy.
A

Simple sugars
3-D
crystallization

66
Q

____– a substance that has an affinity for moisture, also referred to as hygroscopic substances.

-This is ultimately related to their ability to form ____ bonds with ____.

A

Humectant
hydrogen
water

67
Q

Inversion refers to the process where ___ is hydrolyzed to ___ and ____, which are then called ___ ___.

-Inversion can be induced by __, ___, or a special enzymes called ___.

A
sucrose
fructose
glucose
invert sugars
heat, acid
invertase
68
Q

Sugars undergo __ ___ reactions that promote important functional characteristics

Oxidation of the aldehyde group in sugars causes a loss of ___ and converts it to an ___.

Reduction of the ___ group of reducing sugars causes the formation of __ ___, which are moderately sweet.
Ex: ___ and ___

A
oxidation reduction
sweetness
acid
carbonyl
sugar alcohols
mannitol and sorbitol
69
Q

Sweetness is probably the most notable functional characteristic of __ ___, although ___ varies between different sugars.

-___ is usually used as the reference with other sugars.
____>___>____>___>___>___

A
simple sugars
sweetness
Sucrose
Fructose>sucrose>
glucose>maltose>
galactose>lactose
70
Q

Effect on texture through their interaction with ___.

-Sugar can provide ___, ____ (e.g. in baked goods) and can influence other texture promoting compounds such as __.

A

water
bulk
tenderization
starch

71
Q

Polysaccharides:
Also called ___ ___ because of their large size.

-Polymers of monosaccharides and classified as either:
_____ (3-10 units)
_____ (>10 units)

A

complex carbohydrates
Oligosaccharides
polysaccharides

72
Q

Oligosaccharides
Ex: ____ and ____.

  • Present in ___ ___.
  • Not digested in the __ ___ but are fermented by microorganisms in the ___ ___.
A
raffinose
stachyose
dried beans
small intestine
large intestine
73
Q

Polysaccharides are much more ____ in foods than oligosaccharides and are commonly used as ___ to food for specific aspects of functionality.

A

abundant

additives

74
Q

Beta-glucans:

-___ of glucose.
-Considered a ___ __ ____.
-Found primarily in __, __, and ___
-Have been found to lower ___ __(FDA allows this claim).
-Used as a __ __ in many different manufactured food products.
___ – used in baked goods, fillings and frostings, frozen desserts, salad dressings, etc.

A
Polymers
soluble dietary fiber
oats, barley, and yeast
serum cholesterol 
fat replacer
Oatrim
75
Q

Cellulose:

-Most ___ of all carbohydrate polymers.
-Structural component of all __ __.
-The main source of __ __ __.
-Microparticulate form of cellulose:
Used as a __ __ and to increase dietary fiber in foods.

A

abundant
plant cells
insoluble dietary fiber
bulking agent

76
Q

Dextrins & Maltodextrins:

  • Both are derived from the breakdown of ___.
  • Have ___ glucose chains than starch but are still considered polysaccharides.

-The term dextrin is generally applied to any __ molecule that has undergone ___, usually by __.

A
starch
shorter
starch
degradation
heat
77
Q

_____ are more specifically related to commercially generated products, usually from cornstarch.

-Used in sauces, baked goods, processed meats as fat replacer and bulking agent.

A

Maltodextrins

78
Q

Fructooligosaccharides:

  • Polymers containing primarily ___, usually in association with ___.
  • Found in a variety of ___ including garlic, onions, bananas, etc.

-Considered ____ because they are not broken down in the __ __ and make it to the large intestine where they nourish good bacteria (___).

A
fructose
sucrose 
plants
prebiotics
small intestine
probiotics
79
Q

Inulin: Dietary Fiber

  • ___ is a type of fructooligosaccharide found in onions, asparagus and especially chicory root.
  • Serves as a ___ to stimulate the growth of good bacteria.
  • Can be used to adjust ___ attributes.
A

Inulin
prebiotic
textural

80
Q

Pectic Substances:

  • ___ molecular weight polysaccharides found in plant cell walls, primarily for ___.
  • Composed of ____ acid units some of which are methylated, which determines functionality.
A

High
support
galacturonic

81
Q

Pectic Substances:

-___ chemically distinct substances:

  1. ____ – nonmethylated and found in immature fruit
  2. __ __ – methylated and produced during ripening
  3. __ ___– demethylated derivative of pectinic acid and associated with overripe fruit
A

three
Protopectin
pectinic acid
pectic acid

82
Q

Pectic substances:

Degree of ____ (_____) deterimines functionality. High methoxyl (HM) pectin have > __% methylation, whereas low methoxyl (LM) pectin generally has < __% methylation.

A

esterification
methoxylation
50
30

83
Q

Pectic Substances:

-Pectin ____
Pectins are able to form ___ ___ (sols and gels).

A

Gelation

colloidal dispersions

84
Q

To convert a HM pectin sol to a gel it is necessary to reduce the association of pectin with ___ by incorporating ___ and reduce the __ __ between pectin molecules.

A

water

sugar repulsive forces

85
Q

LM pectin can be converted into a gel without ___ by adding ___ ___ such as calcium.

Thus, LM pectin is used in the manufacture of __ __ ___.

A

sugar
divalent cations
sugar free jelly

86
Q

Starch is the predominate source of __ __ in the world’s food supply.

It is a ___ of glucose molecules, found in two forms:
____– a straight chain.
_____ – numerous branches.

A

dietary energy
polymer
amylose
amylopectin

87
Q

Starch:

Packaged in the plant as __ __.

Starches that are high in ___ can form gels.

Starches high in amylopectin can’t but do increase in ___.
\

A

starch granules
amylose
viscosity

88
Q

Starch is often modified to change its ____.

An example of a modified starch is ___ ___, which is used in instant pudding and pie filling.

A

functionality

pregelatinized starch

89
Q

Starch Gelatinization:
Starch is not soluble in __ water, but if __ and ___ it undergoes a conversion that is referred to as ____

During gelatinization, the heated starch granules absorb ___ and ___.

  • ___ reaction.
  • Increased ___.
A
cold
agitated and heated
gelatinization
water and swell
Irreversible
viscosity
90
Q

Starch Pasting and Gel Formation:

__ ___ – a starch/water system the has both thick liquid and solid-like properties.

____ can be thought of as a continuation of gelatinization where the thickening of the slurry occurs.

A

Starch paste

Pasting

91
Q

Starch Pasting and Gel Formation:

In a paste, majority of starch granules have ___, producing __ and ___ granules.

____ – the formation of a gel from a cooled paste.
____ ___ – a thick starch/water mixture that has properties of a solid.

A

gelatinized
swollen and disrupted
Gelation
Starch gel

92
Q

Starch Retrogradation:

_____ is the contraction of starch gels due to interactions between amylose molecules.

As the gel tightens it can __ water, which is referred to as ____.

A

Retrogradation
lose
syneresis

93
Q

Vegetable Gums:

Vegetable gums are a broad category of ___ ___ that contain a variety of sugars including __ and ___.

A

complex polysaccharides

pentoses and hexoses

94
Q

Gums are derived from a variety of sources including __ __ (__), seaweed (___), and microorganisms (___).

A

plant seeds (guar)
carageenans
xanthan

95
Q

_____– proteins are good foaming agents because they can reduce interfacial tension and allow air to be incorporated into liquids.
Egg white meringues.

A

Foaming

96
Q

____– some proteins can form three dimensional networks that allow incorporation of water and form gels.
Collagen that is used in Jell-O™ products.

A

Gelation

97
Q

______– functionality is often dictated by solubility, which is affected by pH, temperature, etc.
Certain applications such as edible film manufacture require highly __ ___.

A

Solubility

soluble proteins

98
Q

___-____ ___– This is the ability for a protein to bind water and is due to its hydrophilic components.

Water holding capacity is lowest, which means ___ is lowest at the ____ (__), where the charge on the molecule is neutral, which reduces the water protein interactions and maximizes the protein-protein interactions (causes protein to precipitate out of solution).

A

Water-holding Capacity
solubility
isoelectric pH (pi)