Chapter 6 Flashcards
Color– color is what our __ ___ when ___ ___ strikes an ___.
-function of the ____ of the light reflected by the ___ of the ___.
eyes perceive visible light object wavelengths cones retine
Cones are sensitive to ___, ___, or ___ color.
red, green or blue
Lightness and darkness are registered in the ___.
rods
Light striking an object can be ___, ___, or ____.
absorbed, reflected or transmitted
Transmitted means goes ___.
Reflected ___ ___.
through
bounces back
Visible light occurs between the wavelengths ___ and ___ in the ___ ___.
380nm and 780nm
electromagnetic spectrum
Food reflects a variety of ____, which determines the ___ that we perceive.
-Ability to see many different shades of a certain color due to the fact that the ___ types of ___ overlap in their ___ to color.
wavelengths color three cones sensitivity
Color can be classified according to its ___, ___ and ___.
hue
chroma
intensity
Color can be classified according to ___ qualities:
- ____ – actual color name. (__, ___, ___)
- ____ – clarity and purity of color. (___)
- ___ – degree of lightness or darkness.
3
hue (red, blue, green)
chroma (saturation)
intensity
___ of ___ also affected by light distribution.
Surface of foods
Color of food is due to ____ molecules.
pigment
There are primarily ___ different kinds of pigment molecules in food:
- ______ - plants
- ____ – plants
Anthocyanins, anthoxanthins, betalains - _____ - plants
- _____– animals
4 Chlorophylls Phenolics Carotenoids Myoglobin
_____ can derive pigmented compounds from plant foods that they eat.
Animals
Myoglobin is a ___ ___ with an ___ containing a ____ group called ___ (iron porphyrin ring).
- Responsible for ___ ___ in ___ tissue.
- Ultimately responsible for the ___ color of muscle foods.
globular protein iron prosthetic heme storing oxygen muscle reddish
Myoglobin: Can bind ___ because of the ___ structure of ___ and because of the ___.
oxygen
tertiary
globin
heme
Myoglobin
- _____ polypeptide
- ___ and ___
- ______________ ring
- __ ___ units
- ___ in center – can bond to any atom able to donate electrons
Single Globin and heme iron porphyrin 4 pyrrole Fe
In living animals, myoglobin ____ oxygen. Upon ____, this no longer happens.
stores
slaughter
Slaughter:
- Meat exposed to oxygen – ___ ____
- Continued exposure – oxidation – ___/___
- Nitrate cured – ___ ____
bright red
grey/brownish
pink color
Whether or not myoglobin is ____ , the ____ state of the ___, and _____ of the ___ molecule all contribute to different ____ of meat.
oxygenated oxidation iron denaturation globin colors
Also, the ___ can be nitroslyated through ___, or bonded with ____ due to ____ action, which will affect the ___.
heme curing sulfur bacterial color
Heat and meat color:
Appearance changes in __ ways:
-____ denaturation (~___ degrees F)
-____ denaturation (~___ degrees F)
2
Myosin 120
myoglobin 140
Judging doneness by color: -Rare – \_\_ \_\_\_ -Medium – \_\_\_\_ -Well – \_\_\_\_\_\_ Can be \_\_\_\_\_
red juices
pink
clear
misleading
The color of fruits and vegetables is due to the ___ major groups of ____ compounds:
- _____
- _____
- _____
three pigment Phenolics Carotenoids chlorophylls.
All pigment compounds contain ___ ___ ___.
(_______)
- This allows for ___ ___ which in turn produces ___.
- ______ ____ are spread across the atoms.
- Their ____ across carbon-to-carbon bonds gives ____.
conjugated double bonds C=C=C=C electron resonance color -Resonance electrons movement color
Phenolics:
Anthocyanins - __ ___, ___ to ___-___ in color, ____, which contain at least ___ ___ rings.
- Valuable ___
- Readily ___ into surroundings
- e.g. ____
water soluble, purple, orange-red. flavonoids, two aromatic
antioxidant
bleed
blueberries
Phenolics:
Anthoxanthins – ___ ___, ___ to ___ in color, ___.
-e.g. ____
water soluble white yellow flavonoids cauliflower
Phenolics:
Betalains – ____ ____, ___ to ____, ____.
- Sensitive to ___ & ___
- e.g. ___
water soluble purple yellow flavonoids heat light beets
Chlorophylls:
- ___ soluble, ___, ____ with ___ at center plus ___ (hydrocarbon tail).
- Chlorophyll a – ___ ___ ___
- Chlorophyll b – ___ ___
Lipid green porphyrin Mg phytol bright blue green olive green
Chlorophylls:
- Susceptible to __ ___ changes during ___
- Loss of ____ tail
- Removal of ____ from center
2 chemical
cooking
hydrocarbon
Mg
Carotenoids:
- ___ soluble, ___ to ___, ____.
- Absorbs ___ & ___ wavelengths
- Relatively ___ & soluble in ___/___
- e.g. ____
Lipid orange yellow isoprenes blue green stable fats/oils tomatoes
Colorant:
A ____ used as a __ ___ to impart a particular ___ to food.
- ____ (ex: ___, ___, ___)
- ____
pigment food additive color natural tumeric, annatto, paprika synthetic
Food, Drugs, and Cosmetics Colorants (FD&C colorant):
- Colorants certified as ___ for use in food, drugs, and cosmetics.
- FDA classifies all colorants as either ____ colorants or ___ colorants.
- All FD&C are ____.
safe
FD&C
exempt
synthetic
Dyes: ___ soluble ___ used to ____ ___ food products.
-e.g. ____
Water chemicals color entire lollipops
Lakes: __ pigments used to ___ the ____ of foods or __ ___ products.
-e.g. ____
Precipitated color surface fat based chocolates
Exempt Colorants:
- These are generally of ____ origin such as ___ and __ ___ extracts.
- ____ ____ – derived from the controlled heating of glucose.
natural
annatto
grape skin
Caramel Color
Caramel color:
-Produces a complex of compounds due to the ___ ____.
caramelization reaction
Cochineal Extract:
- Formerly exempt as of ___ ___.
- Derived from ___ ____.
- Red color is due to ___ ___, which is a __ ___.
- Used in ____, marinades, ___, ____, pie fillings, etc.
Jan 2011 cochineal insects carminic acid phenolic acid beverages cookies desserts
Flavor: property of __ ___ and ___ ___ of the human body.
food material
receptor mechanisms
Flavor involves both ___ and ____ as well as other ____ factors all perceived by ____ sensors in our body.
taste
odor
sensory
physicochemical
Flavor: four basic tastes through taste receptors on the tongue.
- ____
- ___
- ___
- ____
sweet
salty
sour
bitter
Flavor: A ___ taste sensation has been described as ____. (past ___ years)
-Some have suggested that astringency is also a ____— not a ____, it’s a _____.
fifth UMAMI (20) taste flavor sensation
Chemical reaction takes place between molecules in ___ and ___ buds.
- This sends a ___ signal to the ___ that distinguishes the ___.
- ___ ___ sensitive to ___/___
food and taste nervous brain taste mouth cells touch/irritatoin
-____ is more complicated and not as well understood as ____.
- Thousands of odor compounds are sensed by ____ receptors in the ___ ___.
- ___ ___ are volatile
- ___ detection is much ____ than taste detection. If something stinks, its way worse than if something tastes bad.
Odor taste olfactory nasal cavity aroma chemicals odor more
Compounds that are sensed as taste are ___ ___.
-___, ___, ___, and ____ compounds contain hydrophilic functional groups.
water soluble
Sour, salty, bitter and sweet
-___ is primarily associated with acids
sour
- ____ with salts
salty
-___ with sugars
sweet
-____ with a variety of specific compounds such as ____. In ___ and ___.
bitter
quinine
coffee
chocolate
Umami is associated with __ ___ such as __ ___ and ___ ___. (____)
5’-nucleotides
inosine monophosphate
monosodium glutamate (MSG)
MSG:
- Active portion is __ ___
- Lend added dimension of ___ to foods (___, ____)
glutamic acid
flavor
savory
brothy
MSG:
First coined in 1908, skepticism continued until ___
-Concluded animals do have ___ ___ for MSG
-MSG blamed for “___ __ ___”
2001
taste receptor
“Chinese restaurant syndrome”
Astringency:
- Neither ___ nor ___ but a ___ sensation.
- The most well recognized astringent compounds are ____.
taste nor aroma
tactile
tannins
Tannins bind with ___ in saliva.
- Responsible for the ___ ____ effect of some fruits such as cranberries.
- Also important in the taste __ ___
proteins
saliva
lip puckering
red wine
Pungency- the sensation of “___ ___” in the mouth.
- Due to ____ compounds in ____ ____ such as horseradish and especially hot chili peppers.
- Pungent molecules cause the _____ which varies in ___ and ____.
"spicy heat" mouth chemical cruciferous vegetables sensation intensity duration
Pungency:
The specific compound in hot ____.
- Measured using an _____ (based on ___ ___ sensations) method developed by a scientist named ___.
- Thus the term Scoville heat unit (___).
- Low heat chilies: ___-___ Shu
- High heat chilies: _____ Shu
Capsaicinoids organoleptic human sensory Scoville Shu 200 – 2,500 70,000
More recently, ____ methods (___) have replaced the ____ system because they are more ____.
instrumental
HPLC
Scoville
reliable
Cooling Sensation:
- The ___ of ___(____) is sensation of coolness in the mouth.
- Cooling sensation is characterized by the most notable compound responsible for it – ___, a ___ ___.
- Generates ___ __ and ____.
- Used as flavor in ___, baked goods, __ ___, candy.
opposite heat pungency menthol, a cyclic alcohol minty flavor and aroma gum ice cream
Most foods have much different flavors in their ___ and ___states.
-Cooking process has a profound effect on ___ and ____.
raw
cooked
meat
bread
Bread:
- _____ reaction
- _____ contributes to flavor and aroma.
- Tends to be lost quickly due to its ____.
- This is why the aroma of day old bread is not as pleasant as freshly baked bread.
-Production of ___ during ___ ___.
maillard Pyrazine volatility alcohols yeast fermentation
Flavor of cooked ____ is highly complicated.
- Involves ____ products as well as ___ __, ___, ___, and ___generated during the cooking process.
- These are products of degradation of ___, ___ and other components of the ___ cells.
meat maillard amino acids, peptides, nucleotides and volatiles protein lipid muscle
Food ____ isolate and develop flavor compounds and additives.
flavorists
Process and Reaction Flavors:
Produced by ____ mixtures of ingredients
- ___ flavors, ___ oils, ___, ____ flavors, oleoresins, process flavors, reaction flavors.
- ____ extract– 13.35 g vanilla bean/gl OF ____. No more than ___% alcohol. No ___.
- ____ imitation– ___ by products. chemicals.
heating Artificial essential extracts natural VANILLA alcohol 35 sugar VANILLA wood
_____ Flavor produced through chemical synthesis
artificial
Essential Oil obtained from ___ matter by ___ ___, retaining the characteristic ___; a concentrated ___ flavor extractive
plant
steam distillation
flavor
natural
_____- Flavor obtained through the use of alcohol as a solvent
extract
______ _____ -Flavor obtained from natural sources
natural flavor
-___ ___: The dominant, initial aromatic flavor of a substance
top note
Producing Food Flavors:
- Reaction flavors are generated under _____ conditions for the purpose of producing ___ ___ ___.
- The process usually involves ___ ___ that produce appropriate __ ___.
- The targeted predominate flavor characteristic is called the __ __.
- e.g. Producing a ___ ____ flavor.
controlled food flavor additives combining precursors aroma compounds top note cheese process
Enzyme-Produced Flavors:
- Many flavor additives are generated by ___ or ____ processes.
- e.g. ___ to develop cooked meat flavor
- ____ is added to meat and heated and held at optimal temp for enzyme.
- This ___ the meat and then heated to ____ the enzyme.
- Can be concentrated further to produced “___” notes.
enzyme fermentation Enzymes Protease liquefies deactivate "cooked"
Enzyme-Produced Flavors:
- Enzymes also responsible for ___ produced in ___ ___ foods.
- ___, ___, ___, ___ ___.
flavors naturally fermented chocolate cheese coffee hot sauce
Enzyme-Produced Flavors:
- Enzymes can be ___ from ___, ____ and ____ that are grown ____.
- Different flavors that result from yeast fermentation depends on ___ ___, ___ ___, and ____ conditions.
- Used in ___ and ____ industries.
harvested bacteria yeasts molds industrially growth medium yeast strain fermentation brewing baking
Enzyme-Produced Flavors:
- ___ ___ to produce baked bread flavors.
- Requires the breakdown of the yeast to remove ___ ___ material and yield __ __ extracts.
Yeast fermentation
yeast cellular
pure flavor
______ – a substance that has a flavor of its own at the level at which it is used in a food.
e.g. ____
flavoring
vanilla
____ ____– do not impart flavor themselves, but intensifies the flavors that are naturally present or added to foods.
e.g. ____
flavor enhancers
salt
Flavor enhancers:
-_____ ____ – A protein breakdown product obtained by chemical or enzymatic action.
- Generates ___, ___ ___, etc.
- These compounds provide ____, ___ ___, or ___ enhancement.
- ___ ___ ___ (__): Made from soy and is used as an extender or flavoring in meat and dairy products.
protein hydrolysate peptides, amino acids flavor nutritional value flavor Hydrolyzed vegetable protein HVP
Flavor encapsulation– applied to flavors to offer ___, ____, and ___ ___.
-Involves the ___ of ___ compounds.
Provides ___ ___ from high heat, acid, oxygen, thus making them ____ during ____.
Used in the food industry to aid in ___, ____, ___ ____ or flavor ____.
stability convenience timed release coating flavor temporary protection stable storage mixing distribution flavor incorporation stability
___ ___ – unwanted flavor development in foods due to internal chemical changes.
- Different from ___ ___ normally associated with the food product.
- _____ - a fishy off-flavor in dairy products.
- ____ - a rotting off-flavor.
off flavors
characteristic flavors
trimethylamines
putrescene
____ – result from external contamination from the environment during processing, distribution or storage.
These compounds can contribute to a __ ___ at very ___ ___.
taint
desirable flavor
low concentrations
Flavor Degradation Processes:
- ___ ____- due to the release of short chain free fatty acids.
- Caused by ___ and ___. - ____ ____– due to the oxidation of ___ ___ that results in the production of volatile ____, -___, ___ and ____.
- Caused in part by ___ and ___.
hydrolytic rancidity heat lipase oxidative rancidity unsaturated fat aldehydes, ketones, alcohols, acids heat light
___ ___ ___: Occurs in reheated meat products resulting in an unpleasant, stale taste.
- Due to the ___ of ____ in ___ ___.
- ____ is more susceptible than ___, ___, than ___.
- Can be prevented by using ___ ___, ___, and ____.
Warmed over flavors (WOF_ oxidation phospholipids cell membranes pork beef, turkey, chicken controlled heating, reheating, antioxidants
Food texture:
Refers to the perception of food ___ when a food is held by the fingers, pushed by the tongue against the palate or chewed by the teeth.
-_____: is related to texture as it encompasses the sensations experienced during the mastication of food products.
structure
mouthfeel
Measuring food texture:
- Different devices have been developed to obtain __ ___ of ____.
- ___ ____ ____.
objective measure
texture
human sensory panels
____ is often classified by the objective measures that can be made:
- Microscopic & macroscopic ____.
- Resistance to ___ ___ (___ ___)
- Resistance to _____.
- Resistance to ____ etc.
texture structure cutting force (shear force) deformation flow
____ is the specific study of the flow of matter in response to applied force.
- Tells how a ___ ___ will ___.
- How a ___ will be ___ by the ___.
- How ___ it takes for the __ ___ to be ___ from the ___.
Rheology fluid food flow fluid sensed tongue long fluid food cleared palate
____ is the resistance to flow.
- ___ have low viscosity whereas ____ foods have high viscosity.
- Low viscosity- ____
- High viscosity- ___
viscosity fluids semisolid milk honey
Solid foods do not generally ___, but can be ____ or ____ as indications of ___ ____.
flow
deformed
sheared
textural properties
Texture Parameters for Solid/Semisolid Foods:
Cohesiveness/chewiness: ____ vs ____ vs ____
Fracturability: ____ at which a ___ food ___
tender chewy tough force solid splits
Texture Parameters for Solid/Semisolid Foods:
Hardness: ____ vs ___ vs ____
Springiness – elastic: When ___ is ____, item returns to ____ shape
Springiness- plastic: Force results in an ____ that does not ___ ___
soft firm hard force removed original impression spring back
Ingredients that can be incorporated into food products to influence texture are called ___ ___.
- Increase ___
- Promote ___
- Increase ____ by __ ___
- Stabilize ___
texturizing agents viscosity gelation firmness water binding emulsions
___ ___ ____– moisture of food and manner which it is chemically positioned has a great influence on texture
- More __ ___ (___ __ ___) , more ___ and ___.
- ___ water activity foods having a __ ___ texture.
- Low water activity foods tend to be ___ and ___.
water based systems free water (high water activity) tender moist intermediate dry firm hard crisp
___ ___ ___– the influence of fat on texture is primarily derived from its ___ form and __ ___, which can contribute to a smooth, creamy texture.
e.g. The influence of __ ___ on the texture of __.
Fat based systems crystalline melting point cocoa butter chocolate
Chemistry of texturizing agents:
- Primarily ___, ___ ___, and ___, usually of ____ origin, such as ___ and ___ ___.
- Provide ____ by way of their ability to form __ of ___ ___.
polysaccharides, vegetable gums, proteins, animal, collagen, whey protein
functionality
gels
increase viscosity
Polysaccharides: Increase the ____ and apparent ____ of ____ products.
-Carrageenan in chocolate milk creates __ ___ that breaks when the milk is ___.
- Form ___ that provide essential functionality.
- ___ in ____ manufacture.
viscosity richness fluid weak gel poured gels pectin jelly
Fat Replacers – generally classified as either a ___ ___ or ___ ___.
fat substitute
fat mimetic
___ ____– have the same physical properties as a fat and replicate fat functions.
e.g. _____
fat substitute
olestra
____ ____ - do not have all of the essential character such as heat transfer or flavor carrier, but does provide textural similarities.
-Accomplished the combination of ____ such as ___ or ___ ___ and ____.
fat mimetics polymers starch vegetable gums water
Sugars: Reduce the ability for ___ ___ or ___ ____.
-Increases _____ without forming ___.
starch gelatinizaton
protein gelation
viscosity
gel
Gelatin- is a ____ agent derived from ___ when the tropocollagen superhelix is degraded by ___, ___, or ___.
texturizing
collagen
heat
alkali acid
Gelatin is the dried product of ___ ___, which forms a __ –(__ ___) when added to __ ___.
- When cooled becomes more ___, eventually forming a ___ ___ ___.
- The gel is stabilized by __ __ at ___ zones.
- Allows water to be trapped within the ___ ___ of the gel network.
collagen degradation sol (partial solid) hot water viscous 3 dimensional gel noncovalent bonds junction open portions
Meat tenderization can be achieved to a degree by reducing the strength of ___ through a similar degradation of the tropocollagen molecule with the addition of ___ and ____ such as ___ ___ and ___.
collagen heat acids lemon juice vinegar
Commercial meat tenderizers contain ___, which degrades both ___ and ___ proteins.
protease
collagen
myofibrillar
