Dimensions of food studies Flashcards
(114 cards)
1
Q
define Food science
A
is the application of the basic sciences and the engineering of food to study the functional physical chemical and biological nature of food and the principles of processing
2
Q
define food
A
any substance that provides nutrient’s to nourish the body
3
Q
define food microbiology
A
the components of foods
4
Q
define food and nutrition
A
any operation that alters the value of food for a specific prupose
5
Q
Food science is influenced by?
A
Consumer selections and preferences
6
Q
Food science involves
A
- the study of nature of food and its composition
- behavior of food in different conditions
- causes and prevention of spoilage basic principles of processing and preservation
- basic improvement of food quality
- sensory properties
7
Q
what is food engineering?
A
raw food is processed or preserved
8
Q
what is food microbiology?
A
microbial ecology related to food spoilage
9
Q
what is food and nutrition?
A
composition/ properties that have health effects
10
Q
what are the significance of food science and technology
A
- Food supply regulation
- providing for consumer convenience
- providing for mobility/ travel
- waste utilization and reduction
- economic gains
- contribute to hunger/undernourishment epidemic
11
Q
what are primary nutrients
A
CHO, Protein, Lipids
12
Q
what are secondary nutrients?
A
Vitamins/ minerals/ enzymes/ flavors/ acids/ pigments
13
Q
what role does water have in the body
A
one of the most important nutrients
1. occurs in food extracellularly and intracellularly
14
Q
what role does water have on food
A
responsible for: dispersing medium / solvent/ phase/ food preservation/ spoilage/ texture/ interaction with other nutrients
15
Q
who are the 5 major influencers of the Food Marketplace? and which is the most influential?
A
Consumers--> most influential farmers/fishermen food scientists food transport agribusiness
16
Q
What are some factors that influence consumer food choices?
A
- sensory factors
- nutritional criteria
- budgetary criteria
- environmental influences
- social/ cultural criteria
- religious criteria
- psychological
17
Q
what are the consumer trends
A
- Hemp/CBD
- online shopping and delivery
- snacking
- immune supporting
- wellness
- comfort foods
- plant based foods
- packaging
- calming
- beverages
- functional ingredients
- meal kits/ frozen foods
18
Q
are are examples of credible sources
A
USDA
19
Q
what are examples on misinformation?
A
media/ bloggers
20
Q
where does CBD come from?
A
cannabis plant
21
Q
how is CBD different from THC
A
CBD does not have the psychoactive component
22
Q
Why is it an emerging ingredient? (benefits)
A
Helps with 1.stress 2. seizures 3. inflammation, 4. pain insomnia 5. anxiety (mental health disorders) 6. IBD/IBS 7. nausea 8. migraines
23
Q
what system does CBD interact with?
A
Endocannabinoid system
24
Q
what is the difference between organic and natural
A
Organic: has legal protection (since 1990)
-no hormones, antibiotics, GMO petroleum based, sewage sludge-based fertilizers, conventional pesticides, or ionizing radiation
Natural: NO legal protection
- only if a food item is free of added color, artificial flavors or synthetic substances
25
what is genetic engineering?
developing new products with a desired trait through genetic modification
26
what are products of genetic engineering?
genetically modified organisms (GMO)
| -plants or animals
27
How are GMOs regulated?
FDA: regulates safety of GM crops/ GRAS
EPA: pesticides (PIP) food that had utilized genetic modification
USDA: safety of other plants/ responsible for labeling
28
what are Functional foods?
foods that claim to have additional physiological benefit beyond its nutritive value
29
what are types of ingredients are often isolated for this?
```
Phytochemicals
Anthocyanins
carotenoids
polyphenols
fiber
sterols
stanols
```
30
what is fusion?
liquid to a solid
31
what is condensation
gas to a liquid
32
what are the characteristics of water?
polar
surface tension
neutral pH
colligative properties: high because it is able to act as a solvent specific heat: high (takes a lot to change the temperature)
latent heat change in state
solvent: dispersing medium, essential nutrients etc
33
how much energy does a solid have?
the least amount
34
how much energy does a gas have?
the most amount of energy
35
why is water polarity important? why is water referred to as the universal solvent?
1. influences surface tension and the ability of something to dissolve in a medium
2. becasue water is able to dissolve more substances than other liquids
36
what types of bonds form between water molecules as a result of their polarity?
Hydrogen bonds
37
discribe what causes surface tension?
the top layer of water does not have more water about it so it is not able to bond to more carbons so oxygen will form hydrogen bonds between each other on the top layer
cohesive nature of water due to waters polarity
38
what is the significance of waters pH
water is neutral
pH is the relatice number of the h ions to the OH molecules.
high numbers of h+=acidic(low pH)
high numbers of oH= basic high pH
39
Define colligative properties
the binding together of molecules
40
what impact water's colligate nature?
number of solutes
41
how are waters colligative properties impacted when salt is added?
vapor pressure decreaseing
freezing point decreasing
boiling point increasing
42
what is vapor pressure?
it is the vapor over the liquid medium equilibrium
43
what are the factors influence solubility?
increases with temperature
| lowers with the presence of solute
44
what us specific heat?
the amount of heat required to raise the temperature of 1 gram of substance by 1 degree
45
what is the specific heat of water
1cal/gram
46
is waters specific heat high or low compared to other substances
high
47
what roles does the specific heat play into?
important for temperature regulation
48
what is latent heat?
when the temperature of a substance does not change the temperature but it does change the state
49
what types of latent heat?
```
heat of fusion (when substances solidify)
heat vaporization (when substances become vapor
```
50
what happens when liquid changes to ice?
fusion
| hydrogen bonds are forming between molecules and there is a RELEASE OF ENERGY
51
what happens when ice changes to liquid water?
melting
| energy is taken in some hydrogen bonds are broken
52
what happens whenthe temperature of liquid water increases?
the calories of heat are being added to met waters specific heat
53
liquid water changes to steam
latent heat
vaporization
energy is applied
hydrogen bonds are broken
54
what happens when steam changes to liquid?
latent heat
condensation
energy is removed
hydrogen bonds are formed
55
what happens at a molecular level when water freezes?
molecules move slower
| @4degrees water is less dense and has increased in volume
56
what structure does water form at 0degrees
a crystal lattice
57
explain what factors affect the freezing point of water
addition of soluble substances (lowers the freezing point)
| preventing water from freezing
58
what happens when water reaches it boiling point?
vapor pressure of the liquids overcomes atmospheric pressure (hydrogen bonds break when water is heated and temperature rises)
59
what is the boiling point of water?
100
| 212
60
explain the factors affecting the boiling point of water?
1. atmopheric pressure: higher the pressure higher the vapor pressure needed to overcome it
2. altitude: increases so the temperature required for water to boil is lower (Atmos pres. decreases as altitude increases, loner cooking times are due to the lower temperature of of boing water)
3. pressure cooker: rises atmophic pressure which makes the boiling point high (higher the temperature of boiling water the shorter the cooking time)
4. adding soluble substances pr substances that ionizes, reduces, vapor pressure and makes the boiling point higher (due to the vapor pressure being reduced and then increasing the boiling point
61
what are some functions of water in food?
1. Solvent
2. dispersion medium
3. hydrates
4. promote chemical rxn
5. heat transfer/ cooking medium
6. microorganisms
62
how does sugar and salt act molecularly in water?
salt and water act as solutes and dissociate/ ionize in water (inoic bonds between + and -)
water= solvent
63
what is the difference between hydrolysis and condensation rxn?
hydrolysis: adds water to bonds to break then apart
| condensation removes water from bonds to form bonds
64
compare free water and bound water
free water: free flowing
bound water: in structure of PRO, CHO, FAT/ not easily separated from food/resistant to freezing/ not available to dissolve salts, sugars, acids (important to food texture)
65
what is water activity?
the degree to which water is bound of free within food
66
what is the range of water activity?
0-1
zero- low activity
1- pure water
67
what are some examples of food with higher water activity, that are prone to spoilage or contamination by microogramisms
fresh meat, fruit and vegtables
68
no microbes can reproduce at a water activity below
0.5
69
explain what factors affect water activity
temperature
other food ingredients
preservation methods
adding solutes
70
what are two main ways that energy can be supplied to food?
mechanical- physical movement
| heat: radiation, conduction, convection, induction
71
what type of energy is transferred to food through physical movement?
mechanical energy
72
is Mechanical enerfy an efficient way to supplying ebergy to food?
no it only supplies a same amount of energy
73
what macronutrient can be altered through this type of energy transfer?
proteins can be denatured
74
how does radiation transfer heat to food?
direct transfer of heat energy to the surface of food
75
what are the 3 types of food radiation?
infrared
microwaves
irradiation
76
what is infrared radiation?
electromagnetic waves or rays in the infrared range are transferred from heat sources --> food surface only
77
what are examples of infrared radiation?
broiling
heat lamps
heat from sun
78
what is microwave radiation?
waves casued by vibration of dipolar molecules(water fat sugar)
79
how does microwaves affect food molecularlly?
friction between molecules generates heat within the food
80
what are standing times and why are they important while microwaving?
conduction of heat energy through food
| important for dense food (meat)
81
what are disadvantages of microwaving
browning reactions do not occur
| un-evening heating
82
what is irradiation? what are the 2 main purposes of irradiating foods?
the application of ionizing radiation to food
| purpose: improve safety and extend life of food
83
why is food irradiated
to reduce microorganisms
84
how does irradiation kill bacteria?
high energy ionizing radiation breaks chemical bonds
| microbes and bacteria die
85
how does irradiation affect a food?
breaks chemial bonds in food
causes changes in food
1. leafy greens turn mushy/2. slow to ripen/3. can destroy nutr,/ 4, control for formation of compounds formed by radiation/ 5. research doesn't show identifiable problems
86
does irradiation cause induce radioactivity? why or why not?
No
food does not come into contant with radioactive materials
too much can casue a disruption in energy balance of food items making them unstable but FDA puts a limit on the radiation allowed
87
describe conduction
direct transfer of energy from one molecule to the adjacent molecule in a continuous and progressive fashion so that heat can pass from its source (soild)
88
describe convection
is the transfer of heat through air or liquid, as liquid is heated the molecules move apart become less dense and rise to the surface getting replaced by the cooler denser (liquid/ air)
89
what is induction
special induction coils create magnetic current that heats pans
90
what types of pans are necessary for induction stoves?
iron pans are required
91
what is mass transfer in foods?
movement of a food component into or out of a food that is being heated
92
what are some examples given in class of mass transfer?
ex: water moving into or out of a food
| water moving from the surface of food to the cooking medium surrounding air?
93
what is a dispersion
a mixture of two or more substances
94
describe how true solutions, collodidal dispersion, coarse dispersions are different in terms of their particle size
true solution<1 millimicron
colloidal medium
coarse dispersion: >1 millimicron
95
Compare "solvents" and "solutes" and give an example of each
solutes: salts, sucrose, lactose vitamins
solvents: water
96
as temperature increases the amount of solute that will dissolve in a solvent?
increases
97
Compare unsaturated, saturated and supersaturated solutions
Unsaturated: solution could dissolve more solute at a particular temperature if added
saturated: solution has dissolved maximum amount of solute possible at a given temperature
supersaturated solution has dissolved more than the maximum (due to the addition of heat) crystallization occurs
98
compare the continuous and discontinuous phase of a colloidal dispersion
continuous phase is the solvent
discontinuous phase solute (what is being dispersed)
C before D
99
name and define the five types of colloidal dispersions
1. sol / solid in liquid/ milk
2. Gel/ liquid in a solid/ gelatin
3. Emulsion/ liquid in liquid/ oil in water
4. foam/ gas in liquid/ whipping cream
5. suspensoid/ gas in a solid/ foam candy
100
understand the concept of a colloidal dispersion changing into a different colloidal at different temperatures
when pectin chills it forms bonds and traps water so it is no longer pourable and syneresis occurs: the seeping of water
101
what are some basic principles and examples of emulsions?
1. Emulsion is: liquid-liquid system of two immiscible substances
2. substances separate with time
102
what are factors that affect stability?
1. viscosity of continuous phase
2. size of discontinuous phase
3. ratio of phases
4. presence of stabilizing agents
5. temperature
103
what are examples of emulsion
1. butter/margarine (w/o)
| 2. mayo (oil in water
104
what are emulsifying agents?
molecules with Hydrophilic head and hydrophobic tails
105
how do they work in stabilizing emulsions?
the can increase stability of emulsion by interfacing between phases
106
what are common emulsifying agents?
lecithin (and soy lecithin)
107
be familiar with the 3 type of emulsions
1. permanent: enough emulsifying agent totally cover interface between phases
2. semi-permanent: stabilized by viscosity of continuous phase
3. temporary: little emulsifying agent highly fluid shake immediately before use
108
what are examples of course suspensions?
oat flakes in water
109
what is the basic chemical formula for carbohydrates?
(CH2O)n
110
what are some basic characteristic of carbs
1. provide majority of energy needs
2. regulation of blood glucose levels
3. dietary fiber soluble and insoluble
4. simple and complex sugars
111
what are functional properties of sugar?
sweetness, flavoring, chemical flavoring, chemical reactivity, texturing, preserving
112
what are the classifications of simple carbohydrates?
Simple:
1. monosaccharides: glucose, fructose, galactose
2, disaccharides: lactose, sucrose maltose
113
what are the classifications of complex carbohydrates?
Oligosaccharides --> 3-10 sugar units
| polysaccharides --> 10 sugar units
114
how are pentose and hexose sugars different?
pentose: found in vitro deoxyribose
| hexose : found in glucose, fructose galactose
