Food Science: Starch, Sugar, Water, Food Prep Basics Flashcards
1
Q
- Making food edible
- Increasing palatability
- Destroy Pathogens
- Increase digestibility
- Increase Nutritive value
- Improve shelf life
- Improve texture, flavor and color
are all
A
effects of cooking
2
Q
What types of food contain pathogens?
A
meat, fish, poultry
3
Q
What is a relative measure of hotness or coldness
A
Temperature
4
Q
What is a measure of the average kinetic energy of the molecule that compose it?
A
temperature
5
Q
What is the temperature scale for fahranheit?
A
32-212*F (range 180)
6
Q
What is the temperature scale for celcius
A
0-100*C
7
Q
What is the temperature scale for Kelvin?
A
0-373 (C +273)
8
Q
KNOW CONVERSIONS
A
k
9
Q
At what temp does water boil in F?
A
212
10
Q
What is body temp in F?
A
98.6
11
Q
What temp does water freeze in F?
A
32
12
Q
What is absolute zero in F
A
-459.67
13
Q
Energy front he source is absorbed by food and translated to us by the way of _____-
A
temperature
14
Q
What are the three ways of transferring energy?
A
radiation
conduction
convection
15
Q
What is the transfer of heat through a smooth, ceramic surface by a coiled electrical apparatus buried underneath?
A
Induction
16
Q
What are two cooking sources for radiation?
A
Broiler & Grill
17
Q
What is a direct transfer of heat energy from its source to the surface of the food?
A
Radiation
18
Q
When rays reach food surface, energy is absorbed and produces heat by increasing molecule
A
vibration
19
Q
True or False:
Radiant waves or rays can only heat the surface of food?
A
True
20
Q
What is the transfer of energy tom one molecule to the adjacent molecule in a continuous and progressive fashion so that heat can pass from its source, through a pan, and ultimately throughout the food being cooked?
A
Conduction
21
Q
What is the coldest point in conduction?
A
The center
22
Q
What is the transfer of heat by the circulation of currents of hot air/liquid resulting tom the change in density when heated?
A
Convection
23
Q
In convection, heated material has ___________density
A
reduced/lower
24
Q
True or False: In Convection, as the less dense, hot substance rises, it pushes aside the denser, cooler material and sink to the bottom
A
True
25
At what state are water molecules lined up closely together?
Solid (ICE)
26
At what state are water molecules moving away from each other but do not escape?
Liquid (WATER)
27
At what state are water molecules moving so far apart that they escape into the air?
Gas (STEAM)
28
at what state does water have the lowest energy?
Solid (ICE)
29
At what state does water have medium energy?
Liquid (Water)
30
At what state does water have highest energy?
Gas (steam)
31
As water cools, energy is _____
released
32
As energy is removed, molecules move slower and slower, until at ____ organized bonding pattern between molecules begin to appear
4*C
33
What is thhe amount of energy released/absorbed during a change of state without a change in temperature
Latent heat
34
What are the two types of latent heat?
1. heat of fusion
| 2. heat of vaporization
35
What is the heat/energy released in the conversion of water into ice (80cal/g of water)?
Heat of fusion
36
What is the heat/energy absorbed when in the conversion of water into steam (540 cal/g of water)?
Heat of vaporization
37
What is the transfer of heat/energy in the conversion of steam to water
Latent Heat of Condensation
38
What is the pressure exerted as molecules attempt to be in the gaseous rather than the liquid state?
Vapor pressure
39
Vapor Pressure
Pvap
40
With the increase in temp, molecules move more rapidly, this increasing the tendency of molecules to escape front he liquid and becoming ____
vapor
41
^ temp >
^Pvap
42
Liquid boils when Pvap just exceeds
Patm
43
Patm is 76cmHg or
101.325 kPa
44
At standard atmospheric pressure, water freezes at ___*C and boils at _____*C
0*C
100*C
45
Solute reduces
Pvap
46
What are two soluble substances
sugar and salt
47
Because of solutes, there is a freezing point _____
depression (ice cream)
48
Because of solutes, there is a boiling point ______
elevation (candy making)
49
When solute is involved, it reduces Pvap, and will have to boil at much higher ten to exceed Patm and escape. Also works the same for freezing must be
j
50
What else influences boiling point?
altitude
51
Lower Patm in the higher altitude will result in
lower boiling point
52
Per 500 ft rise,
Tboil drops 1*F
53
Per 960 ft rise, Tboil drops
1*C
54
Vaccum pan =
lower Patm
55
Patm is lowered, thus booing point is
lowered
56
Pressure cooker = higher, therefore tight fitting lid traps steam, pressure builds raising temp well about 100*C, increasing the
boiling point
57
heat cooks food, therefor the ^ altitudes makes for
longer cooking time
58
What are the two types of water in foods?
Free water and bound water
59
What type of water is able to dissolve and dilute substances?
Free water
60
What type of water is bound to other substances and lack of/limtited flow proportions and solvent capability?
bound water
61
Bacteria grows best w/ _______ _____. Enzymes grow best w/ free water, making product perish easily.
free water
62
example of food products with free water?
fruit
63
Bacteria and enzymes cannot freely use ___ _____, therefore products last longer
bound water
64
example of food products with bound water?
bread
65
What is a ratio that won't go past 1?
Water activity (aw)
66
What is a measure of water availability?
aw
67
non-volatile substances lowers
water activity
68
Water availiabity determines
perishability
69
^ bound water > V aw > V perishability > ^Shelf life
k
70
Perishibility of 2 foods with same _______ may differ due to different aw
% moisture
71
What are three methods to reduce aw?
Dehydration
Freezing
Sugar/salt
72
1. Dehydration eliminates ____ ____
2. Freezing makes _____ ______
3. Sugar/salt increases _______ ___ _____
1. free water
2. H20 immoble
3. bounding of H20
73
Who needs the most water? Bacteria Molds or Yeasts?
Bacteria, then yeasts, then molds
74
mole solutes,
^ osmotic pressure
75
What causes water to be drawn to solutes, which has higher osmotic pressure?
osmosis
76
What are dispersions in which ions or molecules no larger than one millimicron are dissolved in a liquid (usually water)?
True solutions
77
What are two types of solutions?
solute and solvent
78
What is a substance dissolved in a liquid to form a true solutions? (sugar)
Solute
79
What is a liquid in which the solute is dissolved to form a true solution (water)
Solvent
80
What type of solution is capable of dissolving additional solute at the temperature of the solution?
unsaturated solution
81
What type of solution containing as much solute in solution as possible to dissolve at that temp?
saturated solution
82
What type of solution containing more solute that theoretically can be dissolved at that temp, a station created by cooling a heated saturated solution carefully?
supersaturated solution
83
What is unlike solutions and not all particles dissolve homogeneously?
Colloidal dispersion (proteins, starches, fat)
84
What is the medium surrounding all parts of dispersed phase?
COntinuous phase
85
What phase distributed in discountinous fashion throughout the entire colloidal system?
Discontinuous (dispersed phase)
86
The dispersed phase typically is the less amount mixed
in food ratio
87
What is an example of an emulsion?
salad dressing
88
What is an example of an oil in water emulsion?
mayonnaise
89
What is an example of an water in oil emulsion?
butter
90
What is an example of an sol?
gravy
91
What is an example of an gel?
baked custard
92
What is an example of an foam?
egg white foam
93
What is an example of an suspensoid?
whipped gelatin
94
What are the four types of sugar?
1. Monosaccharides
2. Disaccharides
3. Oligosaccharides
4. Polysaccharides
95
Glucose, fructose, and galactose belong to
monosaccharides
96
maltose, sucrose, lactose belong to
disaccharides
97
raffinose and stachyose belong to
oligosaccharides
98
galactose, glucose, and fructose belong to
raffinose
99
raffinose and galactose belong to
stachyose
100
digestible starch and indigestible fiber belong to
polysaccharides
101
monosaccharides and disaccharides are
simple sugars
102
polysaccharides, such as digestible starches and indigestible cellulose are
complex carbohydrates
103
1. sweetness
2. sollubility
3. crystalization
4. browning reactions
5. hygroscopicity
6. texture
7. fermentation
8. preservation
are functions of
sugar
104
what if the reference sugar?
sucrose because its table sugar
105
sweetness determinants include
type of sugar
| and concentration
106
v temperature of food/drinks >
^ perceived sweetness
107
How many grams of sugar will dissolve in 100 ml of water is
solubility
108
what sugar is gritty refrozen ice cream
lactose
109
Most soluble in water : greatest to least
Fructose, sucrose, glucose, maltose, lactose
110
solubility... ^ temp, ^ amount
can dissolve
111
solubility...^ concentration, ^
Tboil
112
what % sucrose solution is a saturated solution
66.6%
113
what % sucrose solution is a super saturated solution?
>66.6%
114
browning aka
non-enzymatic
115
What are two types of browning?
1. caramelization
| 2. maillard reaction
116
dry heat + sugar =
caramelization
117
caramelization decreases
perceived/actual sweetness
118
Sucrose > clear liquid (320*F) >
brown liquid (338*F)
119
reducing sugar + amino acids =
maillard reaction
120
what environment is needed for a mallard reaction
heat, alkaline, moisture
121
What is absorption of moist when sugar is caked/lumpy?
hygroscopicity
122
What is the most hygroscopic?
fructose
123
what carries mouthfeel?
texture
124
what food source of microorganism?
fermentation
125
what is 60-65% sugar?
Preservation
126
To be labeled HFCS what % of fructose must there be? (50% glucose)
40%
127
what is 75% sugar, 25% water?
corn syrup
128
what is stored in plants as seeds, roots, and tubers?
starch
129
what are the sources of starch?
1. cereal grains
2. Legumes
3. Root/tubers
130
corn, wheat, rice, grain sorghum, and oats are
cereal grains
131
potato, sweet potato, arrowroot, cassava, and sago are
root/tubers
132
what is Linear, a 1,4 and is cloudy and mostly cereal starches?
amylose
133
What has a high viscosity, translucent mostly root starches and has a 1, 4 and a1,6 at branch
amylopectin
134
If recipe calls for corn starch and you only have tapioca, do you use less, more or the same?
Less
135
What is heat without moisture?
dextrinization
136
What is hydrolytic breakdown of starch effected by intense dry heat and producing dextrine (short units of glucose)
dextrinization
137
what is heat with moisture
gelatinization
138
what is swelling of starch granules and migration of some amylose into the cooking water when starch is heated in water as a thickiner
gelatinization
139
The process in which starch becomes soluble, binds water and forms gel is
gelatinization
140
During gelatinization, heat energy breaks H bonds, then results in water entry and leaching of
amylose
141
1. source of starch
2. heating time and temperature
3. agitation or stirring
all effect
viscosity
142
what is further leaching of amylose from the granule and implosion of granule with a complete loss of granular structure and lowers viscosity
pasting
143
Adding heat to a gelatinized starch, will give you
pasting
144
cooling a gelatinized starch will give you
gelation and retrogradation
145
a pH of wat lowers viscosity?
below 4
