Exam 4 Flashcards
1
Q
Food vs Feed difference
A
Psychological
Both are:
nutritious, safe, palatable to the consumer
2
Q
Why is feed ground instead of just cracker
A
To improve feed efficiency (wt gain per feed consumed)
reduce transport loss
increase storage space efficiency
3
Q
Methods of grinding grain for feed and the form of the feed in each method
A
Roller mill when fed as mash
Hammermill when fed as pellets
4
Q
Roller milll process
A
steam if going to crimp
dry mill
crimp (same as bumped)
5
Q
Hammer mill description and product
A
Blunt force against screen (hammer doing most of work)
fine particle size
6
Q
Grinding disadvantages
A
dusty product (health concerns, trucking losses)
segregation of additives
Low bulk density (takes up alot of space to store/transport)
7
Q
Pelleting process
A
Grains (and other minerals, vit, enzymes) mixed with steam
flows into pelleting chamber
compressed into a die
pellet drops out and is cooled (size/shape vary based on animal)
screened for size (anything not right gets re-extruded)
8
Q
Pelleting advantages
A
improved handling
improved feed efficiencies (partially gelatinized the starch, denatured proteins, more homogenous mix)
less loss
9
Q
Aquatic feeds are ___ if it is a floating or slow sinking feed
A
extruded
10
Q
Aquatic feeds are ___ if it is a feed that sinks quickly
A
pelleted
11
Q
Aquatic feeds
- protein levels
- ingredients
A
high protein level
up to 50 diff ingredients that must be equally distributed in the pellet
12
Q
Pet food processing options
A
Dry expanded - pellets or extruded
semi-moist= extruded (no expansion)
soft expanded = water added in extruder, extruded
Snacks and treats = baked or extruded
13
Q
Rheology definition
A
study of how materials deform, flow, or fail when force is applied
-complex systems
14
Q
Viscous flow
A
material will flow under stress but not recover immediately (honey)
15
Q
Newtonian Viscosity
A
Ideal viscosity, is not affected by shear rate
just water
16
Q
Non-Newtonian Viscosity
- definition
- challenge
A
Shear rate and time affect viscosity (real-life)
-viscosity decreases with increased shear
(stir something faster and it gets thinner)
-must measure shear at diff points to get diff viscosity readings (challenge)
17
Q
Elasticity
definition and bonding
A
Material will deform but returns to its original size and shape instantaneously when the force is released.
(highly cross-linked, large molecular wt- rubber band)
18
Q
Viscoelastic (definition and bonding
A
Viscous but elastic.
Cross connected with non-covalent bonds that are constantly bonding and breaking. Does not return to original shape.
19
Q
Deformation
A
alter the shape by pressure or stress
20
Q
stress
A
force exerted on the material
21
Q
strain
A
resistance to stress
22
Q
Moldulus
A
Mathematical interpretation of stiffness
-stiff substance doesn’t move when you push on it
23
Q
Storage moldulus
A
measure of energy stored
E prime = tension or compression
G prime= sheering or twisting motions
24
Q
Loss modulus
A
Measure of energy lost as heat
E double prime = tension compression
G double prime= sheering twisting
25
It is impossible to define stress on dough because
dough's constantly changing shape and pressure points
26
Traditional instruments for measuring dough rheology during mixing
Farinograph and mixograph
| -not true rheological but still widely used
27
Farinograph looks at
protein characteristics of the flour. How much water to get to 500 consistency (page 3 rheology)
dough characterisitcs in unchanging conditions
-not a true rheological test
28
Alveograph looks at and procedure
```
-Measure of extensibility and dough strength
Biaxial extension (two directional stretching of dough)
Blow a bubble till it pops
-not a true rheological test
```
29
Extensograph
Measure time related changes and changes with ingredients
- dough shaped in a cylinder then stretched
- not a true rheological test
30
Rheology: Traditional instruments used post-mixing
Alveograph and extensograph (involves stretching the dough)
31
Dough physical chemistry instrumentaiton
lubricated uniaxial compression
-dynamic rheological testing
considered to be the best indication of what is happening with the dough
32
Batter traditional instrumentaiton
Amylopgraph and RVA
| flow viscometers
33
Batter physical chemistry instrumentation
Oscillatory probe rhometers
rotation viscometers
(stirring resistance)
34
Bread ingredients
```
Flour
Water
Yeast
Salt
Many optional (nonessential) ingredients
```
35
Flour parameters for bread making (protein, type)
Hard wheat
8-12% protein
some damaged starch as indirect CHO source for yeast and to increase water absorption
36
Arbinoxylans in flour
absorb huge amount of water
| -this is why we can have 100% rye bread, high ARBXL hold dough together
37
Flour protein role in bread making
gluten matrix
- structure
- air nuclei
38
Starch role in bread making
Gelatinzation
- takes up water (from other components=drying)
- contributes to setting the structure
39
Water role in bread making
#1=plasticization of gluten and starch
Solvent
metabolism support of yeast
controls feel of dough
40
water characteristics affecting bread making
amount (too much = sticky, too little = no ferment, no gluten formation, crumbling)
Hardness (soft water= soft dough, hard = stiff product)
mineral content
41
Yeast role in bread making
```
CO2 production (leavening)
changes in dough rheology
```
42
Salt role in bread making
```
Flavor enhancer
Rheological effect (strengthens protein matrix which improves gas retention and extension)
```
43
Sugar (nonessential) role in bread making
Fermentable CHOS
Darker crust color
sweetnes
44
Vital Wheat Gluten (nonessential) role in bread making
Increase absorption and hydrate proteins
increased volume
increase processing tolerance
45
Alpha-amylase (nonessential) role in bread making
Fermentable CHOS from malted barely
| slows post-bake firming = softer breads
46
Enzymes added (nonessential) role in bread making
Xylanases, Lipases, Oxidases
dough strengtheners
trying to replace chemicals with enzymes
47
Fats or oils (shortening)
| (nonessential) role in bread making
Increased tenderness
increased loaf volume
reduced firming rate - longer shelf life
48
Mineral yeast food
| (nonessential) role in bread making
Nitrogen to support metabolism
| co-factors for yeast enzymes
49
Oxidants
| (nonessential) role in bread making
Improve loaf volume and crumb grain
| not needed when grain is allowed to naturally age
50
Reducing agents
(nonessential) role in bread making
chemical process
Reduce mixing time
decrease dough elasticity (for doughs that give too much snap back like pizza dough)
work by reducing protein size which makes them less tightly linked, allowing them to hydrate and develop much faster
51
Sufactants / Emulsifiers
| (nonessential) role in bread making
```
Dough stabilizers (strengtheners)
crumb softeners
```
52
```
Mold Inhibitors
(nonessential) role in bread making
```
Minimize mold growth, usually by reducing pH
53
Non-Fat Dry Milk
| (nonessential) role in bread making
Functions as yeast food (nitrogen, and yeast co-factors)
| high in essential amino acid lysine
54
```
Milk Replacement
(nonessential) role in bread making
```
Cheap milk alternative
| better processing tolerance
55
Sponge-dough (water content)
more water than a straight dough per weight flour
56
Types of industrial production methods for bread dough
straight dough= oldest
sponge dough = North America
Short-time = UK
57
Straight dough bread process and
| Is it used commercially why/why not?
```
Mix ingredients to "optimum"
ferment and punch
divide and round
proof
mould
pan
proof
bake
```
Not common commerically because chew texture and flavor isn't as good. Hard to do on a large scale
58
Sponge dough process steps
| \
```
Mix sponge with part ingredients (to a loose/weak dough)
Ferment longer, NO punching
Mix rest of ingredients
short rest (floor time)
THEN SAME AS STRAIGHT DOUGH
divide and round
intermediate proof
mould
pan
proof
bake
```
59
why is sponge dough used commercially
More tolerant to process variations,
| final product is softer, sweeter, and has more ferment flavor than straight dough
60
Goal of dough mixing
Gluten development
By hydrating proteins so they interact to form gluten network
Incorporate air
nuclie/ nucleation sites. Other gases in the air dissolve into the water in the dough, Nitrogen remains as a gas and fills the bubble.
61
Why overmixing is an issue
Dough becomes very sticky and extensible, would be a problem on a commercial scale
62
Fermentation in dough
- goal
- results in
Gas production
Yeast fermenting CHOs to CO2, ethanol, and others
CO2 diffuses into N bubble and enlarges the nuclei. Gluten network expands with the pressure and grows more highly cross-linked/stronger.
63
Yeast can ferment these CHOs
Glucose, sucrose, dextrose, fructose
64
Purpose of the punch during fermentation
subdivides the gas cells
| redistribute sugars so they are closer to the yeasts
65
The most critical part of fermentation in the industry process is
The first 45-60min
| Requires best environment (temp and fermentable CHos available)
66
Proofing -purpose
continued fermentation
restricted by the pan
greatly increases volume (final leavening)
67
In baking, most heat comes from
the pan, there is a gradient within the dough
68
Baking - oven spring
Increase in volume in the oven due to gases becoming less soluable (in liquid) as the temp rises, so they diffuse back into the nuclei as gas for additional expansion. Yeast also increases activity until its so hot it dies
69
Gluten has to be strong enough to _____ but not too strong to _____
allow expansion
| inhibit exansion
70
Processes/changes that happen during baking
```
Heating
gas production (oven spring)
crust formation
becomes gas continuous
browning
cooling
```
71
Crust formation in baking is due to
dehydration and evaporative cooling (not starch gelatinization)
72
Why does bread become gas conitinuous in baking
starch gelatinizes (pulls water from proteins) and proteins denature and harden in a highly cross linked state.
73
Maillard browning
reducing sugars reacting with amino acids
74
Role of gluten proteins in mixing
hydrate and develop during mixing
- entraps air
- impacted by reducing or oxidizing agents
Glutenins corss linking and glidens are hydrating. When the two interact, we get a viscoelastic dough
75
Role of gluten proteins in fermentation
slows gas diffusion until the gluten network ruptures
76
Role of gluten proteins in make-up
align and strengthen dough (hold shape in mold and sheeting)
77
Role of gluten proteins in the oven
Denature in the oven so the network can rupture and become gas continuous
78
Water extractable arabinoxylans do what to the dough
increase viscosity and increase water uptake
| so viscous it can entrap air and form rye bread
79
Lipids role in bread making
Polar lipids stabilize the nuceli gas cells
Interact with enzyme
overall, improve bread volume
80
Crust changes during staling
Toughens
Loses crispness (changes from glassy to rubbery state)
mainly water migration from the crumb
81
Crumb changes in staling
Becomes crumbly, harsh, and dry
loses flavor
loses moisture
usually blamed on starch retrogradation = firming but that is not that simple bc we can reheat the bread to refresh the texture
82
Amylose retrogradation is completed during
cooling
83
Amylopectin retrogration plays a major role in
changes over time by organizing with itself, amylose, with protein, etc
84
Whole grain bread consists of what parts of the kernel
All the pieces present in ration from nature, not the hull
85
Pseudo-cereals
Seed is predominately starch
| Buckwheat, quinoa, amaranth
86
Wheat bread composition
mixture of refined and whole wheat flours
87
Multi-grain bread composition
Composed of 3 grains, but may be refined flour
88
Rye bread composotion
up to 100% rye due to high levels of arbinoxylans that allow for gas retention and viscosity
89
Sour-dough bread process variation
Yeast produce gas & bacteria produce acid
| Less yeast present, so have a long ferment
90
Sweet dough def
HIgh levels of sugar (10% by wt) use more yeast bc there is a slower fermentation
91
Frozen dough
Short or no fermentation
Must control temp variation during transport and storage to protect yeast and gluten (proteins lose water and it doesn't go back where it came from)
92
Gluten - free bread
No wheat, rye, tricale, barely, maybe oats
-All contain the same amino acid sequence that causes an allergic reaction
No gluten so very hard to do
93
Four essential ingredients of yeast leavened bread
Flour
water
yeast
salt
94
Chemical leavener are generally used with ___ flour
soft flour as we usually are making cakes, cookies, crakers
95
Chemically -leavened product ingredients
```
Soft wheat flour
chemically released leavening gases
water
salt
sugars
fat
```
96
Four means of leavening
Chemical
biochemical= yeast & bacteria
physical = water flashing off as steam
mechanical = air incorporation
97
Baking powder formulation
Based (sodium bicarbonate)
1 or more food-grade acids
filler (usually starch)
98
double acting baking powder
Fast and slow acting (one or more of each rate)
99
acid rate of reaction
measure of speed of reactivity of leavening acids (amount of CO2 released during mixing)
how quickly the acid dissolves and reacts with the soda
100
Fast acid rate of reaction products
All organic acids (tartaric acid/ cream of tartar)
MCP
AMCP (delayed fast, or gradual)
101
Acid rate of reaction slow
SAPP- sodium acid phosphate
SALP- banned bc Al toxicity
SAS (goes off at higher temp than SALP and sulfate weakens dough structure slightly)
GDL
102
Acid rate of reaction totally triggered by heat
DMP (replacing SALP bc no sodium)
| DCPD (happens in the oven, too late for stand alone leavening, so used for pH control)
103
Sulfate effect on crumb - chemical leaveners
courses cell structure, thicker cell walls
| decreases elasticity
104
Ca ions effect on the crumb - chemical leaveners
Finer grain crumb, thinner cell walls
| imparts resiliency to the texture of foods
105
Neutralizing value def and purpose
Measure of available acidity / CO2 releasing power.
How to determine the correct usage level of leavening acid. Wt of soda neutralized by 100 parts leavening acid
106
Ammonium bicarbonate useage
Potential leavener for very porous products. Pores allow gas to escape with ammonia gas
107
Cookie/Sweet buscuit general formulation
```
Soft wheat flour
high sugar
high fat
low water
individually baked
```
108
HIgh lipid and high sugar ___ gluten development
inhibits
109
Cookie rotary mold process overview
Low water
cohesive with pressure
no change in size or shape as baked (oreo)
**no leavening**
110
Cookie wire cut process overview
High sugar, high fat
extruded and cut
spread during baking
co-extruded = variation (fig bar)
111
Wire cut cookies
| -how is air trapped in mixing
solid sugar granulaes cut into the fat which traps the air
| -slow gluten hydration
112
Wire cut cookies
| -spreading because
decrease in viscosity due to:
fat melts
sugar melts
leavening gases released
113
Wire cut cookies
| -stop spreading when
protein pass through the glass transition to set the strucutre
(little if any starch gelatinzation)
114
Sugar Wafers process
No sugar, very bland flavor
Want very low viscosity and no aggolmeration (clogged machinery)
baked between plates
115
Cookie quality end goals
size and shape
texture
visual texture
116
Crackers general formulaion
```
Low sugar
moderate fat
low water
chemical, biological, and/or physical leavening
sheeted and often laminated
```
117
Saltine process steps
sponge and dough fermentation (yeast and bacteria fermentation)
sheeted (some gluten develop. maybe cross-sheeting)
and laminated
docked
baked
118
cross-sheeting
develop gluten strength at 90 degree angles for more uniform shrinkage
119
Docking
punching holes through dough to tie layers together
120
Lamination
multiple sheets are stacked ontop of eachother and then rolled to final thickness
121
Saltines conveyor belt during baking
mesh to allow even evaporation
| prevents checking
122
Snack crackers processing
straight dough
Tunnel oven, mesh conveyor
sprayed with an oil as it leaves the oven to coat the surface to prevent moisture uptake, and add flavor
wide varieties of products available
123
Backing power buscuit
chemically leavened bread but higher fat (don't want even distribution of fat)
mix, sheet, cut, bake
refridgerated dough is popular
124
How does refrigerated baking power biscuit dough work
Made under cooled conditions and put in tubes. elevate temp slightly to allow SAAP to proof and seal the tube.
when opened rapid expansion and then secondary slower SAAP is leave and will leaven in the oven.
125
Cake ingredients
HIgh fat
high sugar
high water (for starch gelatinization which is different than the other chem. leavened products)
Aerated structure (mixing is critical to trap it)
126
specific gravity
weight of a volume of batter to weight of volume of water.
| more air= more specific gravity
127
Structure of cakes is set in baking because of
gelatinization
egg protein denaturation/ coagulation
**not gluten proteins**
128
Low-ratio cakes
less sucrose than flour by weight
| will gelatinze and set structure at a lower temp
129
High-ratio cakes
| ingredients and their functions
```
More sucrose than flour
chlorinated flour (to increase swelling and maintain viscosity as sugars melt)
egg proteins (structure)
shortening (trap the air)
emulsifers (increase batter viscosity)
```
130
High ratio cakes
| multi-stage mixing -def and advantages
creaming fat and sugar to trap the air
then add liquid and other flour in separate steps.
More tolerant to process variations, fine cell structure ad stable viscosity over time
131
High ratio cakes
| single-stage mixing def, disadvantages
cake mix
a way of grindining shortening to coat flour
not tolerant to floor time
132
Angel food cakes
protein foam stabilized by sugar
| little flour added at end to dehydrate foam and set structure
133
pound cakes
1lb flour, butter eggs, sugar
| starch is gelatinized
134
Acids in baking soda determine
timing of leavening
| finished texture
