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FSCN 1011 Exam 2
FSCN 1011 Exam 2
78
Science
Undergraduate 1
11/10/2014

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Term
Ideal solid
Definition
deforms elastically (all energy recovered when stress is removed)
Term
Ideal fluid
Definition
deformation is irreversible, they flow and all energy is lost (will not retain any shape)
Term
Real solids
Definition
can be deformed irreversibly under sufficient force (they creep: steel, cheese, glass)
Term
Real Fluid
Definition
few are close to ideal, water because it retains some shape
Term
visco-elastic
Definition
a food that has the characteristics of both a liquid and a solid
Term
polyglacturonic acid
Definition
the backbone of the pectin molecule is composed of
Term
What types of bonds are used in low and high methoxy content levels?
Definition
Hydrogen bonds hold pectin molecules together in the formation of a gel when the pectin has a low methoxy content. Ionic bonds are the primary bond when there is a high methoxy content.
Term
How do ionic bonds of pectin molecules form?
Definition
The ionic bonds are the result of calcium crosslinks between two pectin molecules.
Term
What are the two different molecular forms of starch (both composed of glucose) found in starch granules?
Definition
Amylose and Amylopectin
Term
What is a vanilla fold?
Definition
beans are less than 25% moistures, 13.35 ounces of bean per fold
Term
What is the process of picking tea leaves?
Definition
After picking chlorophyll breaks down, tannins released, fermentation (natural enzymes), can involve oxidizing enzymes.
Term
What is the green pigment found in tea leaves?
Definition
chlorophyll
Term
What is cowboy coffee?
Definition
Cowboy coffee is when the grounds are thrown into water.
Term
How do you know if a vanilla ice cream has real vanilla?
Definition
Vanilla ice cream: pure vanilla
Vanilla flavored ice cream: synthetic vanilla
Artificially flavored ice cream: no real vanilla
Term
Why is vanilla hard to grow in new regions?
Definition
Can only be pollinated by the Melipona bee or has to be hand pollinated.
Term
What are some types of food extractions?
Definition
coffee (water extraction), tea (water extraction), vanilla (alcohol extraction)
Term
What is the solute and what is the solvent?
Definition
The solute is the mixture component (sugar) in the solution while the solvent (water) is what the solute is dissolved in.
Term
What is an immiscible phase?
Definition
A phase in which two items do not mix (i.e. oil and water). They do not form a homogeneous mixture.
Term
How does an extraction use the immiscible phase?
Definition
Uses two immiscible phases to separate a solute from one phase to another.
Term
What are mechanisms of separation?
Definition
Filters and screens, centrifuges, gravity (liquid-liquid), by hand
Term
What are types of separations?
Definition
solid-solid, liquid-liquid, liquid-solid, liquid-gas, solid-gas.
Term
What does WONF stand for?
Definition
with other natural flavors
Term
Why can vanilla be kept at room temperature?
Definition
due to the alcohol content vanilla can be kept at room temperature.
Term
What is coumadin?
Definition
a banned food additive in the US which can be found in imitation vanilla. Coumadin can cause liver damage.
Term
What gives vanilla its unique flavor?
Definition
Methyl vanillin makes vanilla unique and is what gives it most of its flavor.
Term
What color does anthoxanthin produce in fruits and veggies?
Definition
white to yellow colors (water soluble)
Term
What color does anthcyanin produce in fruits and veggies?
Definition
blues to purples (water soluble)
Term
What color does cartenoid produce in fruits and veggies?
Definition
orange to red colors (fat soluble)
Term
What are the terms for the colors in meat?
Definition
oxymyoglobin, myoglobin, metmyoglobin
Term
What is allura?
Definition
Allura is an artificial red color
Term
What does D & C stand for?
Definition
Drug and cosmetic
Term
What does FD&C stand for?
Definition
food, drug, and cosmetic
Term
What is annatto?
Definition
Annatto is the natural cartenoid extracted from the red, oily outer layer of the seeds of Bixa orellane.
Term
What is caramel color used in and made from?
Definition
Made from caramelized sugar and is use in cola.
Term
What are ways to reduce enzymatic browning?
Definition
Lemon juice or other acids, remove copper as a cofactor, blanch, coo, gas flush (removes oxygen), bisulfates or citrates
Term
What are the three key factors in enzymatic browning?
Definition
color, oxygen, enzymes
Term
What enzymes are involved in enzymatic browning?
Definition
polyphenol oxidase, catechol oxidase which created melanins and benzoquinone, resulting in a brown color
Term
What is the process of enzymatic browning?
Definition
Can change substrates into many products, active site where the reaction takes place, complex substitute binding enzyme, energy barrier activation hump, reactants needs for reaction, inhibition competes with substrate for active site.
Term
What are the two types of nonenzymatic browning?
Definition
Maillard reaction and caramelization
Term
What types of double bonds are in color molecules?
Definition
Complex structure of carbon-carbon bonds.
Term
What is a hue and what are the stimuli of a hue?
Definition
A hue is one of the main properties of color, red, green, blue, and yellow
Term
What is color?
Definition
The capacity of an organism to distinguish objects based on the wavelengths or the light they reflect, emit, or transmit.
Term
What is salt's affect on a foam?
Definition
Slows down and destabilizes, competes for protein.
Term
What are the enemies of foams?
Definition
oil, egg yolks, detergent
Term
How do you block a sulfur bond from forming in a foam?
Definition
Use a copper or silver bowl and add an acid
Term
What do you want to avoid sulfur bonds in foams?
Definition
They cause proteins to force water out.
Term
How do you stabilize a foam?
Definition
The proteins denature (globulins and ovotransferrin). Whipping pulls water and proteins unfold, air impacts the protein
Term
What are types of food foams?
Definition
Meringue, mousse, whipped cream
Term
What is the process of food destabilization?
Definition
gravtitation: causes drainage of liquid to the foam base
osmotic pressure: causes drainage from the lamellas to the plateau borders due to internal concentration differences in the foam
Laplace pressure: causes diffusion of gas from small to large bubble due to pressure difference
Term
What are the two immiscible parts in an emulsion and a foam?
Definition
Emulsion: water and oil
Foam: water and air
Term
What conditions are needed to create a foam?
Definition
mechanical work or energy
surface active components that reduce surface tension
formation of a foam faster than its breakdown
Term
What is a foam?
Definition
A foam is a substance that is formed by trapping gas in a liquid or a solid in a divided form
Term
What foods found in the kitchen can be used as emulsifiers?
Definition
buttermilk powder, protein powder, egg yolks, mustard, honey
Term
What is coagulation?
Definition
occurs upon the excessive heating of an egg
Term
What does heating due to proteins?
Definition
Heating will convert a native protein to a denatured form of the protein. An example is the conversion of collagen in meat to gelatin.
Term
What is lecithin?
Definition
Lecithin is a commercially used emulsifier
Term
What does characteristics does a good emulsifier have?
Definition
a hydrophillic and hydrophobic portion
Term
What are ways to alter viscosity?
Definition
add starch, add gums, denature proteins, add other ingredients, cool it down
Term
What are ways to change density?
Definition
add weight to the oil, do not add water soluble ingredients
Term
What are the theories of homogenization?
Definition
Shear, shatter, attenuation
Term
What are ways to disperse and reduce the size of the dispersed phase?
Definition
shake by hand, whisk, blend, homogenize
Term
What is needed to disperse oil into water?
Definition
energy is needed to overcome the surface tension
Term
What items can be modified to aid in stabilizing a food?
Definition
diameter, viscosity, density, gravity (but not really)
Term
Items of interest in Stokes Law
Definition
diameter of dispersed phase droplets
difference in the density of the two phases
gravity as a separating force
viscosity of a system
Term
What type of emulsions are butter and salad dressing?
Definition
Butter: water in oil
Salad dressingL oil in water
Term
What is flocculation
Definition
the initial contact of one particle to another
Term
What is coalescence?
Definition
when particles lose their identity, you start with many and end with one big oil slick which takes a lot of energy to separate.
Term
What is creaming?
Definition
Creaming occurs when fat droplets are lighter than water and they all rise to the top but they all keep their identity at the top
Term
What are the two phases in an emulsion?
Definition
Dispersed phase: island
Continuous phase: water, what the dispersed phased is mixed into
Term
What is an emulsion?
Definition
an emulsion is a mixture of two or more lquids that are normally immiscible
Term
What are two means by which one can measure the strength of a gel?
Definition
brabender, shear press
Term
What are rennet and chymosin used for?
Definition
Rennet used to be used to cause milk to gel but not chymosin from GMOs is primarily used
Term
When does micelle destabilization occur?
Definition
When you add an enzyme which removes the water
or
when acid is added, neutralizing the charge
Term
What are two mechanisms that prevent micelles from forming a gel?
Definition
Negative charge and water of hydration
Term
What are the primary proteins of milk?
Definition
The primary proteins of milk are caseins which form large clusters called micelles
Term
What is syneresis?
Definition
The cause of water loss in a gel which occurs as junction zones between starch molecules increase in size
Term
What is another name for the staling of bread?
Definition
Retrogradation
Term
What has happened when birefringence is lost?
Definition
The starch granule has undergone gelatinzation
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