Food Science Test 2

Front 1

Triglyceride

Back 1

Storage form of fat; three fatty acid groups with a glycerol backbone

Front 2

Saturated Fatty Acid

Back 2

A fatty acid that does not have unsaturated linkages between carbon atoms

Front 3

Monounsaturated Fatty Acid

Back 3

Fatty acids that have one double bond in the chain

Front 4

Polyunsaturated Fatty Acid

Back 4

Fatty acids that have more than one double bond in the chain

Front 5

Polymer

Back 5

A substance that is composed of multiple subunits linked together

Front 6

Monomer

Back 6

The smallest subunit of a polymer

Front 7

Free fatty acid

Back 7

Fatty acids that are not attached to other molecules

Front 8

Hydrolysis

Back 8

The chemical breakdown of a compound due to a reaction with water

Front 9

Antioxidant

Back 9

A substance that inhibits oxidation

Front 10

Amino Acid

Back 10

A compound that contains a carboxyl and amino group

Front 11

R-Group

Back 11

Side chain of varying atoms in an amino acid; where all A.A.s differ

Front 12

Amino Group

Back 12

Functional group that consists of a nitrogen atom attached to other groups

Front 13

Enzyme

Back 13

A globular protein that acts as a catalyst in a chemical reaction

Front 14

Disulfide Bridge

Back 14

Covalent bonding between two sulfur atoms in a protein

Front 15

Enzymatic Browning

Back 15

When certain enzymes turn fruits and vegetables a brown color

Front 16

Mole

Back 16

Unit of measurement for the amount of a chemical substance

Front 17

Actin

Back 17

Protein that forms microfilaments

Front 18

Myosin

Back 18

Protein that combines with actin to make contractile filaments of muscle cells

Front 19

Collagen

Back 19

Protein found in connective tissue; makes gelatin when boiled

Front 20

Elastin

Back 20

Elastic protein found in connective tissue

Front 21

Myoglobin

Back 21

A red protein containing heme that carries and stores oxygen in muscle cells

Front 22

Denaturation

Back 22

Process in which proteins lose their structure and function

Front 23

Two factors that influence the melting point of a F.A.

Back 23

- Chain length

- Degree of saturation

Front 24

Why do fats have a melting range?

Back 24

Because each F.A. has its own unique melting point

Front 25

Why do fried foods brown?

Back 25

Dehydration of the surface of the food causes Malliard browning

Front 26

Hydrolysis of oil

Back 26

Water breaks the ester linkage in oil with the addition of heat and catalysts

Front 27

Why do short chain sat F.A. and unsat. F.A. undergo hydrolysis faster than long chain sat F.A.?

Back 27

B/c they have a lower melting point and react to hydrolysis faster

Front 28

One good reason to add fresh oil to the fryer

Back 28

To ensure that the oil stays hydrophobic

Front 29

What is the problem with free fatty acids in frying oil?

Back 29

They reduce the surface tension of oil which allows air to be absorbed and oxidative rancidity can occur

Front 30

Where does glycerol in fry oil come from?

Back 30

The breakdown of triglycerides during hydrolysis

Front 31

What is thermal oxidation of fry oil?

Back 31

When the breakdown of products occurs at a faster rate

Front 32

Why keep foods warm after frying?

Back 32

To prevent excess oil absorption when the food cools down

Front 33

What is the isoelectric point of a protein?

Back 33

The pH at which the net overall charge is zero

Front 34

Four structures of a protein

Back 34

1) Primary (amino acid sequence)

2) Secondary (alpha helix/beta sheets)

3) Tertiary (3-D)

4) Quaternary (complex of protein molecules)

Front 35

What type of force holds each protein structure together?

Back 35

- Primary = covalent

- Secondary = hydrogen

- Tertiary and Quaternary = hydrophobic interactions/hydrogen bonds/disulfide bridges/ionic bonds

Front 36

Why can't fresh pineapple be used in jello?

Back 36

There is an enzyme that denatures the protein in gelatin which prevents it from setting

Front 37

Why does fat slow down egg protein coagulation?

Back 37

The fat surrounds the protein strands which blocks them from water and heat

Front 38

Why does acid speed up egg coagulation?

Back 38

The acid decreases the protein solubility in water because its charge is changed

Front 39

What is meant by the water holding capacity of protein?

Back 39

The ability of a protein to hold its own and added water during heating

Front 40

How does salt shift the isoelectric point of a protein to the left (lower)?

Back 40

Due to the chloride effect; chloride ions match to + charges which increases the net negative charge of the protein

Front 41

Why do meats increase water holding capacity the further away from the isoelectric point?

Back 41

B/c myofibrils in the meat open up which allows more water to go in; the charges push the fibers away from each other, creating the space

Front 42

Why are lean protein fibers influenced more by salts and phosphates?

Back 42

B/c they are high in myofibrils and low in fat/connective tissue; the meats charges are held in the fibers which causes more shifts in the iso. point

Front 43

How does adding phosphates decrease cooking loss?

Back 43

It breaks down the structural proteins and calcium cations create links between muscle fibers, creating a "bridge" that retains more water

Front 44

How does salt react with meat proteins to increase water holding capacity?

Back 44

The Na+ and Cl- ions disassociate from one another and are free to bind with the charges on the fibers, which shifts the iso point left and increases water:protein interactions

Front 45

How does temp affect phosphate diffusion in meat?

Back 45

The higher the temp the higher the rate of diffusion

Front 46

Two roles of phosphates in meat

Back 46

- Increase water holding capacity to produce a higher-yielding product

- Improve texture and sensory properties

Front 47

Why add phosphates to restructured meats?

Back 47

To bring back color, structure, and sensory aspects after rigor mortis

Front 48

Which fat will undergo oxidative rancidity the fastest?

Back 48

I DONT KNOW