Chapter 4 Flashcards by Ciera Gray

Foods are made of _____ which is composed of ___ ___, as either _____ or _____.

matter
pure substances
elements
compounds

How well did you know this?

Not at all

Perfectly

Elements are the ____ form of matter - ____ be broken down further.

simplest

cannot

How well did you know this?

Not at all

Perfectly

Compounds are made of ___ or ___ ____, _____ bonded in definite proportions by ____.

two
more
elements
chemically
weight

How well did you know this?

Not at all

Perfectly

Compounds are represented as _____ that depict their _____ _____.

formulas
element
composition

How well did you know this?

Not at all

Perfectly

Important compounds in food science are _____ compounds.

-All contain _____ (___), _____ (__), ____ (__) and sometimes ___ (__), ____ (__)or ____ (__).

organic
carbon (C)
Hydrogen (H)
Oxygen (O)
sulfur (S)
Nitrogen (N)
Phosphorus (P)

How well did you know this?

Not at all

Perfectly

Matter can also exist as ____ in which two or more _____ are combined ____.

-___, ____, _____

mixtures
substances
physically
Solutions, dispersions, emulsions

How well did you know this?

Not at all

Perfectly

_____ – one or two letter designations for elements depicted in the periodic table.

Symbols

How well did you know this?

Not at all

Perfectly

Formulas – depicts all of the ____ in a ____, including ____ as ____ numbers.

elements
compound
proportions
subscribed

How well did you know this?

Not at all

Perfectly

Equations– a ____ description of a ____ ___ using ___ ___ and ____.
Example:

C6H12O6 + 6 O2 6 CO2 + 6 H20 (breakdown of ____)

written
chemical 
chemical symbols 
formulas
glucose

How well did you know this?

Not at all

Perfectly

Chemical reactions - ___/___ interact with each other through ___ ___.

-Results in a ___ ___ with different ___ from the ____.

atoms/molecules
chemical bonding
new
substance
properties
reactants

How well did you know this?

Not at all

Perfectly

Elements interact with one another via ___ ___, which requires ____.

-Only ____ are involved in chemical bonds.

chemical
bonds
energy
electrons

How well did you know this?

Not at all

Perfectly

Electrons are ____ charged and are attracted to ____ charged ___.

___ can be seen as having a series of electron orbits.

negatively
positively
nucleus
atom

How well did you know this?

Not at all

Perfectly

To determine maximum number of electrons in each energy level, use \_\_\_\_.
1st level – \_\_\_
2nd level – \_\_
3rd level – \_\_\_
4th level – \_\_\_

X=2n^2
2
8
18
32

How well did you know this?

Not at all

Perfectly

Most atoms become chemically stable when they have ___ electrons in their ____ shell (____ shell ).

Valence shell is the ____ electron ___.

8
outermost
valence
outer
orbital

How well did you know this?

Not at all

Perfectly

During chemical bonding, ____ elements are ____ according to the ___ given in their ___.
-____ Acid – C3H6O2
-Can be written as a ____ formula in order to ___ the bonding that takes place.
Exmaple: CH3 – CH2 – COOH

reacting
combined
proportions
formula
Propionic
structural
visualize

How well did you know this?

Not at all

Perfectly

Covalent Bonds– occur when ____ are ___.

___, ___, or ___ pairs of elections can be shared resulting in ___, ___, ___ bonds.

electrons
shared
One, two or three
single, double, triple

How well did you know this?

Not at all

Perfectly

__, ___, ___, and ___ have covalently bonded carbon atoms.

-Form the ____ of these molecules

Fats, proteins, carbs, vitamins

backbone

How well did you know this?

Not at all

Perfectly

Ionic Bonds– the ___ of ___ between ___.

Resulting in a ___ ____ shell of both ___.
Elements that ____ electrons become ___ charged and are called ____ (____)
Elements that ___ electrons are ___ charged and called ____ (___).

____ (NaCl) is an example of a compound with ionic bonding.

transfer
electrons
reactants
full
valence 
elements
donate
positively 
cations (sodium)
receive
negatively 
anions (chlorine)
salt

How well did you know this?

Not at all

Perfectly

Hydrogen Bonds– a type of ____ bond with ___ rather than ___ sharing of ___, resulting in a ___ ___.
Intermolecular bonds– ___ between ___ ___ molecules.

covalent
unequal 
equal 
electrons
weak force
bonds
two different

How well did you know this?

Not at all

Perfectly

___ ___ (H bonding) They don’t ___, they just ___ with each other.

Static clinging
share
interact

How well did you know this?

Not at all

Perfectly

Chemical reactions in foods: Generally classified as either ____ or ____ reactions.

-Either type may be either ____ or _____.

composition
decomposition
enzymatic
nonenzymatic

How well did you know this?

Not at all

Perfectly

Composition reactions– __ or ___ substances combine resulting in a ____ ____ (____).

-Synthesis of ____ from ___ ___.

two 
more
single product (A+B=AB)
protein
amino acids

How well did you know this?

Not at all

Perfectly

Decomposition reactions– ___ substance becomes ___ ____ (____).

-____ of ____ yields two ____ molecules.

One substance 
two products
(AB=A+B)
hydrolysis 
maltose
glucose

How well did you know this?

Not at all

Perfectly

In food the effect of enzymes can be either:

Positive- _____ of ____.
Negative- ____ of ___ ___ and ____.

tenderization
meat
browning
cut fruits 
vegetables

How well did you know this?

Not at all

Perfectly

Enzymes are _____ ____ and serve as ____ ____ (cause ____ to speed ___) of chemical reactions.

``` specialized proteins biological catalyst reactions speed up ```

Active site–location where the ____ joins with the ____ to form the ____ ___ ___. -____ ___ region that contains __ ___ that bind, __-____, to the substrate.

``` substrate enzyme enzyme substrate complex Three dimensional amino acids non-covalently ```

Activation energy– the amount of ___ required for a ___ to take ___. -Enzymes ____ the activation energy thus ___ ___ the reaction.

``` energy reaction place reduce activation energy speeding up ```

Enzymatic Hydrolysis - the ____ of large components into ___ ones (___ ___). Ex: ___, ____, ____.

``` breakdown large smaller protein hydrolysis carbohydrases, lipases, proteases ```

Enzymatic Oxidation-Reduction– ___ is the loss of ___ and ____ is the addition of ____. - Ex: the ___ of ___ and ____ via ___ ___. - In nature, they are ____.

``` oxidation electrons reduction electrons browning fruits vegetables polyphenol oxidase coupled ```

Enzymatic Polymerization– occur through ____ reactions (i.e. the ___ of ___ compounds). -When many condensations occur within the same molecule, a ____ is formed.

condensation joining two polymer

Nonenzymatic reactions: as the name implies, these reactions occur in ___ in the absence of an ___ ___. Types include: - ____ - ____-___ - ____ - ___

``` nature enzyme catalyst Addition Oxidation-reduction Hydrolysis Condensation ```

Addition– the ____ of an ____ to a ___. -____ of __ ___ ___ where ___ is added to the ____ bonds.

``` addition element compound Hydrogenation unsaturated fatty acids hydrogen double ```

Oxidation-Reduction– electrons are ___ between ____. -Can affect ___, ___, and ___ of foods. -Oxidation – the addition of ____. Reduction – the gain of ___. -Can be caused by ___ ___, ___, high ___ ____, ___ ___, etc.

``` transferred substances color quality acceptability foods oxygen hydrogen UV Light heat oxygen environment metal catalyst ```

Condensation and Hydrolysis– these can be viewed as _____ reactions. These reactions are generally catalyzed by __ or ___.

complimentary | heat or acid

Condensation reaction– occurs when ___ ___ are ___ together with the formation of a ___ ___ and ___.

``` two molecules joined new product water ```

Hydrolysis reaction– occurs when a molecule is ___ apart in the presence of ___, which is incorporated into the __ ___ products.

broken water two new

Functional groups– ____ of ___ that create certain ____ of ____.

arrangements atoms properties molecules

Functional groups Include: ``` ____ group ____ group _____ group ____ acid group ____ group ____ group ___ group ____ group ____ group ____ groups ```

``` Alcohol group Aldehyde group Amino group Carboxylic acid group Ester group Ketone group Methyl group Phosphate group Sulfhydryl group Ionic groups ```

Alcohol group– ___ or ____. -Important food alcohols include ____ and ____.

OH or hydroxyl ethanol glycerol

Aldehyde group–___ at the end of the ____ which is ___ bonded to ____. -Important in ____ and ___ of foods.

``` carbon molecule double oxygen odors flavor ```

Amino group– contains an ___ ( ___ ) ___ group. -____, ___ and ____ are amines

``` amino (NH2) functional histamine serotonin dopamine ```

Carboxylic Acid– a ___ on the end of a molecule bonded to a ___ and double bonded to an ____. Ex: ___ ____, ___ ___ (____).

carbon hydroxyl oxygen citric acid, acetic acid (vinegar)

Ester group– a carbon double bonded to an ____ and single bonded to a second ___ which is bonded to another ____. -Associated with characteristic ___ of foods.

``` carbon oxygen oxygen carbon aroma ```

Ketones– ___ ___ atom is double bonded to an ____. -Associated with ___ of food (cooking of ___, brewing of ___).

interior carbon oxygen flavor meats, beer

Methyl Group– a ____ bonded to ___ ___. - One of the important building blocks of ___ ___. - Found in ___ and ___.

``` carbon three hydrogen organic molecules pectins gums ```

Phosphate group – a ___ bonded to ___ ___ and double bonded to one ____ and single bonded to one ____. -Added to ____ to improve ____, ___ and ___-___capacity.

``` phosphorus two hydroxyl oxygen oxygen meat texture, juiciness, water-holding ```

Sulfhydryl Group– a ___ bonded to a ___. - Compounds containing sulfhydryl groups are called ___. - Important to ___ of foods (e.g. in ___ ___). - Smell rotten eggs- you are smelling ____

``` sulfur hydrogen thiols structure bread dough sulfhydryl ```

Functional properties of food are the ___ and ____ factors that impact the ____ of food during ___, ___, and ___.

``` chemical and physical behavior formulation processing storage ```

Functional groups_in component molecules play an important role in ____ of the food itself.

functionality

Because most food contains a large proportion of ____, its functionality is a highly ____ ___ relative to the ____ of food.

water critical factor quality

A wide range of functions attributed to water include: - Diluent and carrier of ____ components - ___ for ___ reactions - ___ - ___ of ___ transfer - Participates in ___ ___

``` hydrophilic medium chemical solvent medium heat chemical reactions ```

Water molecule and structure: ___ ___ atoms bonded to ___ hydrogen Each H atom shares an __ ___ with the ___.

``` Two hydrogen one hydrogen electron pair O ```

Oxygen ___ the ___ __ ___ more strongly than the ___. A ___ is established where the oxygen is more ___ charged and the hydrogen is more ____ charged.

``` attracts shared electron pair hydrogen dipole negatively positively ```

This results in hydrogen bonding : - High __ ___ and freezing point - High __ ___ - High ___ ___.

boiling point freezing point vapor pressure interfacial tension

Solubility- the ability to be ___ into solution. -____ compounds disperse readily in water.

dispersed | hydrophilic

Hydration– water molecules ___ and ___ ___ molecules by acting as a ___. -___ molecules

``` contact surround polar solvent Polar ```

Amphilphilic - contain both ___ and ____ regions. -When water interacts with these compounds, ____ are formed. Ex: ___, ___, ____.

polar nonpolar micelles proteins, phospholipids, sterols

Moisture- the amount of ____ in a food.

water

Water activity- the amount of ____ ____ for ____ reactions or to support ____ ___, ___/____ reactions.

``` water available chemical microbial growth enzymatic chemical ```

Water is present in food in ____ states: ___ water, ____ water, and ___ water.

three free structural bound

Free water - participates in ____ reactions and support ____ ____.

chemical | microbial growth

Structural water - participates in ___ reactions and support ___ ___.

chemical | microbial growth

Bound water - tightly associated with ____ ____ and does not act as ___ ___ molecules do. Not available for _____ or ____ ___.

``` food components typical water reactions microbial growth ```

Food acids are primarily ___ ___ based (i.e. ___ acids).

carboxylic acid | organic

Differences in ___, ___ of ____ ___ and ___ of ___ ____ within the molecular structure, all influence the characteristics of the acids.

``` size number carboxylic units location carboxylic acid ```