CHAPTER 11: EGGS AND EGG PRODUCERS Flashcards
(308 cards)
1
Q
Why do nearly all baked goods contain eggs?
A
Their versatility.
2
Q
Today, most eggs come from where?
A
Companies that have flocks of 75,000 hens or more, with some companies having as many as 5,000,000 or more.
3
Q
The average hen lays how many eggs per year?
A
250 to 300, over twice as many as 50 years ago.
4
Q
Why are hens laying twice as many eggs?
A
Improvement of breeding, nutrition, housing, and management practices.
5
Q
Egg have 6 distinct parts. Name them.
A
Thin white, thick white, yolk, shell, air cell, and chalazae.
6
Q
About two thirds of the weight of the edible part of an egg is what?
A
Egg white, about 1/3 is yolk.
7
Q
Overall, most of the whole egg is what?
A
Moisture, with smaller amounts of protein, fat, and emulsifiers.
8
Q
How are the thick and thin whites layered?
A
Thin white has two layers. First is just below the shell, the other is between the thick white and yolk.
9
Q
Another name for egg white is what?
A
Egg albumen
10
Q
Other than small amounts of ____ ______ and ______, egg whites consist entirely of protein and water.
A
mineral ash, glucose
11
Q
While the special mix of proteins in egg white is extremely important to its functionality, egg white is actually mostly what? What %?
A
Water, about 90% and only 10% protein.
12
Q
Compared to yolk, egg white has a very little what?
A
Flavor and color.
13
Q
What happens to thick egg white as the egg ages? What does this do to foams?
A
It thins as the egg ages. As it thins, egg white loses its ability to form foams that are stable.
14
Q
Egg yolks are about half ____ and half ____ ______.
A
moisture, yolk solids
15
Q
As eggs age, yolks pick up what?
A
Additional moisture from the white.
16
Q
What happens when the yolk picks up additional moisture from the white?
A
The yolk thins out and flattens when the egg is cracked into a smooth surface.
17
Q
The yolk has a protective membrane that ______ as it ages. This makes it more difficult to what?
A
weakens, separate the yolk from the white.
18
Q
What does a weak yolk membrane mean for bacteria?
A
It can easily pass through and multiply if eggs aren’t kept cold.
19
Q
The solids in yolks consist of what?
A
Proteins, fats, and emulsifiers, with a small amount of mineral ash and yellow-oragnce carotenoids.
20
Q
Are egg yolk proteins the same as egg white proteins? Explain.
A
No, many egg yolk proteins are lipoproteins, proteins bound to fats and emulsifiers, which are both lipids.
21
Q
% of moisture, protein, fat and emulsifiers, and other (sugars and ash) in whole egg.
A
moisture: 76%
protein: 12%
fat and emulsifiers: 10%
other (sugars and ash): 2%
22
Q
% of moisture, protein, fat and emulsifiers, and other (sugars and ash) in egg white.
A
moisture: 88%
protein: 10%
fat and emulsifiers: 0%
other (sugars and ash): 2%
23
Q
% of moisture, protein, fat and emulsifiers, and other (sugars and ash) in egg yolk.
A
moisture: 50%
protein: 17%
fat and emulsifiers: 30%
other (sugars and ash): 3%
24
Q
Egg white is one of the few foods that is naturally what?
A
Alkaline
25
Fresh egg whites have a pH approaching what? What about as it ages?
8, and this increases to 9 or 10 as the egg age and loses carbon dioxide.
26
Does natural alkalinity of egg whites help reduce bacterial growth?
Yes, but should still be cooked or pasteurized before consumption.
27
Besides egg whites, the only other common alkaline foods ingredients are what?
Baking soda and hard water. Dutch cocoa is also alkaline, but only because it's treated with an alkali.
28
is lecithin a single substance?
No, it's a complex mixture of emulsifying lipids widely found in nature.
29
Besides egg yolks, is lecithin found in other dairy ingredients? Anything else.
Yes, and cereal grains, and soybeans.
30
Is lecithin also sold as a single product?
Yes, as a dark, oily liquid, or sometimes as powder or granules.
31
The emulsifying lipids in lecithin are classified as what?
Phospholipids
32
Do phospholipids molecules look somewhat like triglyceride molecules?
Yes
33
Phospholipids consists of two fatty acids attached to a what?
Glycerol
34
Instead of a third fatty acid (like triglycerides), phospholipids contain what?
So-called phosphate group.
35
What are the fatty acids and phosphate group attracted to?
The fatty acids are attracted to fats and oils (lipids) in food, while the phosphate group is attracted to water.
36
What allows phospholipids such as lecithin to acts as emulsifiers.
Its the ability to attract both water and lipids that allows phospholipids such as lecithin to acts as emulsifiers.
37
The most well-known emulsifier in egg yolk.
Lecithin
38
How much lecithin does egg yolk contain?
10%
39
Like most lipids in egg yolks, lecithin is bound to what?
Lipoproteins
40
The emulsifying lipoproteins provide many functions in food, but most notably what?
Most notably bonding to both water and oil. By bonding to both, emulsifiers and emulsifying lipoproteins hold together, or bind, complex mixtures of ingredients, such as cake batters.
41
An important factor in the color of egg yolk is what? Explain.
Hen's feed. The more carotenoids in the feed, the more yellow-0range the yolk.
42
Wheat, oat, and white corn produce what types of yolks?
Lighter yolks.
43
Alfalfa and yellow corn produce what types of yolks.
both high in carotenoids, produce deeply colored yolks.
44
When feed is naturally low in carotenoids, what can be added for color?
Marigold petals, which are a rich source of carotenoids.
45
Does the hen's feed also affect the flavor of egg yolks?
Yes, this explains why some brands of eggs taste different than others.
46
What is sometimes added to hen feed so that hens are high in this healthful oil?
Omega-3-fatty acids. These eggs will have a different flavor than regular eggs.
47
Eggshell represents how much of the egg's weight?
11%
48
Although it serves as a hard protective covering, eggshells are what? What does this mean?
Porous. This means that odors penetrate eggshells, and moisture and gases (primarily carbon dioxide) can escape.
49
In commercial practice, what is done to eggs for cleanliness?
Washed and sanitized to remove dirt and reduce likelihood of salmonella contamination. They are also lightly coated with mineral oil to delay moisture loss.
50
The use of organic eggs more than double when?
During the 1990s and continues to grow at an annual rate of 15% per year.
51
In response to growing popularity of organic eggs, the US initiated what program?
National Organic Program in 2002 to unify the use of the term organic across the country.
52
Organic growers must be ______, or they cannot use the term organic to describe their products.
certified
53
Organic eggs come from animals that are given no what?
Antibiotics or growth hormones.
54
Organic hens are fed what?
Organic feed, which is produced without using most pesticides, synthetic fertilizers, irradiation, or genetic engineering.
55
Before a product can be labeled organic, who inspects the farm?
A government-approved certifier inspects the farm where the food is grown to make sure the farmer is following all the rules necessary to meet USDA organic standards.
56
Is the safety or nutritional value of organic eggs different from standard?
Not necessarily.
57
White type of hens lay white eggs?
Hens with white feathers and white earlobes.
58
What type of hens lay brown eggs?
Hens with red feathers and red lobes.
59
What % of commercial breeds produce white eggs?
95%, but hens bred in parts of New England produce brown shells.
60
Does shell color affect flavor, nutrition or functionality of egg?
No
61
Eggs contain _____ protective membranes between the shell and white.
2
62
Soon after an egg is laid, an ___ ____ forms between the membranes at the eggs ______ end.
air cell, larger
63
As an egg ages, loses moisture, and shrinks, what happens to the air pocket?
Increases in size. This is why old eggs float in water while fresh ones sink.
64
What are the chalazae?
Twisted white chords that hold the yolk to the center of the egg.
65
What happens to the chalazae as an egg ages?
They disintegrate.
66
Chelsea are an extension of the ____ _____ and are completely ______. Although pastry chefs typically use a chinois or sieve to strain them from certain products, such as custards.
egg white, edible
67
What are shell eggs?
Eggs purchased in their shells, either by the dozen or in flats.
68
One flat holds how many eggs?
2 1/2 dozen or 30 eggs.
69
How many flats are in a case?
12 flats in a case, which means that one case contains 30 dozen or 360 eggs.
70
Shell eggs are sometimes called what?
Fresh eggs
71
Are shell eggs always fresh?
No, they might be several weeks or months old.
72
Shell eggs are sorted and classified according to ______ (quality) and ______.
grade, size
73
What is AAFC?
Agriculture and Agri Food Canada
74
USDA and AAFC offer programs to classify and label eggs but which is voluntary and which is mandatory?
US is voluntary, Canada mandatory.
75
What % of eggs sold in the US are graded by USDA?
30%
76
The three USDA grades for acceptable shell eggs are what?
Grades AA, A, and B.
77
Canada has to acceptable grades, what are they?
A and B.
78
Do quality grades reflect product safety or nutritional quality?
No, and grade B eggs--stored properly--are safe and will have the same nutritional value as high quality.
79
Usually, USDA graded eggs are washed, packed, and graded within how long?
A day to a week of being laid, but they can be legally graded for up to 30 days.
80
Do USDA graded eggs have to be labeled with the date that they were packed and graded?
Yes
81
The sell-by date (also on the package) is defined as no more than ____ days from the time the eggs were packed and graded.
30
82
Most common eggs purchased in a bakeshop?
Grades AA and A
83
Main difference between USDA AA and A eggs is what?
The firmness of the white and the size of the air cell. Only eggs with the firmest whites and smallest air cells can be labeled USDA Grade AA.
84
Why are firm white and yolks particularly important? When are they less important.
Because they hold their shape when frying or poaching an egg. They are less important for baking.
85
Prior to 1998, eggs that were nearing their expiration date could be returned to the packer to be what?
Washed, packed, and graded a second time, extending their usable life. This is no longer allowed in the US for safety reasons.
86
Grade B eggs might have one or more of the following defects.
Stained shells, large air cells, watery whites, small blood spots in the white, or enlarged, flattened yolk.
87
Are Grade B eggs acceptable for general baking?
Yes
88
Do Grade B eggs make good meringues?
Their whites may not while properly if they're watery.
89
Does the quality of eggs reflect age?
No, but quality does decline over time.
90
Will properly refrigerated eggs still lose their Grade AA status? How long does it take?
Yes, they can be downgraded to Grade A in little as a week. In 5 weeks, they will go from A to B, as whites thin and air cells enlarge.
91
Does nutrition value decline quickly as Grade?
No, properly handled eggs will maintain their nutritional value and wholesomeness for quite some time.
92
Are size classifications for eggs different from quality classifications?
Yes
93
How many size classifications are there in North America?
6, all based on minimum weights per dozen; it does not refer to dimensions of an egg or how large it is.
94
The most common size classification for eggs used in a bakeshop.
Large, extra large, and jumbo.
95
What are the 6 size classifications?
Jumbo, extra large, large, medium, small, peewee.
96
How are eggs graded for quality?
Candling is the primary method used.
97
What does candling do?
A bright light passes through the egg and exposes the size of its air pocket, thickness and clarity of the white, the position and stability of the yolk, the presence of blood spots or a developing embryo, and more.
98
When a formula calls for a certain number of eggs, what should you assume?
It's based on large-sized eggs, with the edible portion weighing approximately 1.75 ounces (50 grams).
99
How much of an egg is white and yolk?
2/3 is white and 1/3 is yolk.
100
If a formula calls for 3 extra large eggs, how do you determine weight?
3 x 1.75 (3 x 50g) or 5.25oz (150g).
101
If a formula calls for 3 egg yolks, how do you determine weight?
3 x 0.55oz (17g), or 1.65 ounces (50 grams).
102
If a formula calls for 3 egg whites, how do you determine weight?
3 x 1.2oz (33g), or 3.6oz (100g)
103
Why do individual eggs in a carton still vary in weight?
Because size classifications are determined by minimum weights of an entire dozen.
104
Egg products include various forms of what?
Eggs that are sold removed from their shells.
105
The range of egg products includes what?
Egg whites, egg yolks, and whole egg products refrigerated, frozen, or dried.
106
Liquid and dry egg products have been available for how long?
The late 1800s, but quality was generally poor. Today, 1/3 of eggs used in the US are egg products.
107
Why can most egg products be used in place of eggs in most bakeshops today?
Because changes in processing have improved over the years.
108
Does the viscosity of frozen products change over time?
Yes, but this does not affect their properties.
109
Are egg products steadily replacing shell eggs in the bakeshop? What 2 main reasons?
Yes, the main one being safety. By law, egg products must be pasteurized so they are free from salmonella bacteria. Also, it saves money on labor.
110
Frozen egg whites often contain what? Why?
Added thickener, such as guar gum. Whipping agents--such as triethyl citrate or sodium lauryl sulfate--are also added, sometimes.
111
What does guar gum do for frozen egg whites?
This protects it from ice crystal damage. It also increases viscosity. improving the ability of frozen whites to foam.
112
What do triethyl citrate or sodium lauryl sulfate do for frozen egg whites?
Whip up higher and faster than whites from the shell.
113
How many eggs can be broken in an automated egg breaking machine?
162,000 eggs per hour or 45 eggs per second. Info provided by the American Egg Board.
114
Why are higher amounts of heat desired when pasteurizing foods?
With most foods, high pasteurization temperatures mean shorter heating time inflicts less quality damage to the food.
115
Why can't eggs be pasteurized at high temperatures?
Egg proteins will coagulate.
116
A typical commercial pasteurization process for liquid whole eggs is what?
Heat eggs for 3.5 minutes at 140ºF (60ºC).
117
Can dry egg white be pasteurized a different way?
Yes, they can be held at 130ºF (54ºC) for 7 days.
118
Does pasteurization affect the properties of eggs?
For the most part, no.
119
Advantages of egg products.
Safety, reduced labor, take up less space, no loss due to breakage, longer shelf life (as long as remaining dry or frozen), no leftovers, uniformity in quality.
120
What applications do frozen egg whites not work well on? Why? How can you alter this?
Swiss meringues, because frozen egg whites do not form as firm or stable a foam as whites from fresh shell eggs. Fresh or dried whites can be blended with frozen whites to assure better whipping.
121
Can frozen egg whites be used inmost applications?
Yes
122
What happens to thick and thin egg whites when unthawed?
They may separate, so shake container well.
123
Frozen yolks usually contain what? How much is added?
Added sugar or glucose corn syrup, generally 10%.
124
What does adding sugar to frozen yolks do?
Lowers the freezing point, preventing excess ice crystal damage that causes yolk proteins to gel irreversibly to a thick gummy solid.
125
Are frozen, sugared yolks a thicker consistency than regular shelled egg yolks?
Yes, even after added sugar. This does not negatively affect functionality. In fact, thicker egg yolks might assist in formation of stable emulsions.
126
For general use, how should regular and frozen yolks be substituted? What about custard sauces?
1 for 1, but for products containing high amounts of yolk, such as custard sauce, you may want to adjust the sugar.
127
To make adjustments for sugar, replace each pound of yolks with how much sugared yolks.
1.1 pounds (about 1 lbs, 1.5 oz) of sugared yolks. Reduce the amount of sugar in the formula by 0.1 lbs (about 1.5oz).
128
What causes the grayish-green color to form in eggs?
When eggs are heated, some of the sulfur is released. When sulfur from egg whites combines with egg yolks, an iron sulfide forms. This iron sulfide has a grayish-green color.
129
When is iron sulfide likely to form in eggs?
When eggs are heated too long, or when they are heated in water that is high in iron. High pH also favors this reaction. Recall that the pH of an egg increases as it ages; older eggs are more susceptible.
130
How are the formation of iron sulfide and use of too much baking soda correlated?
Baking soda raises pH, which explains why baked goods with too much baking soda have a slight greenish tinge.
131
Unlike yolks sold frozen, refrigerated liquid yolks don't contain what?
Additives to lower the freezing point and protect the yolks from gelling.
132
How does the gelling of egg yolks affect baked goods?
It reduces their ability to aerate and mix well with other ingredients.
133
Should applications should you never use frozen yolks on?
Biscuit (sponge cake), French buttercream, or bombe mixtures, which rely on whipped egg yolks for volume.
134
What is a pâte à bombe?
French term for a mixture used as a base for making chocolate mousse and other mousse-like desserts.
135
How is pâte à bombe made?
It is made by pouring a sugar syrup that has been cooked until it is 121 degrees celsius (249.8 farenheit) over egg yolks and whipping the mixture until it is completely cold and has transformed into a uniform, unctuous, airy mass.
136
Where would unfrozen egg yolks be of more use than frozen? What applications?
Items that don't need added sugar, such as hollandaise sauce and Caesar salad dressing.
137
Do frozen whole eggs contain yolks and whites in their natural proportions?
Yes
138
Do whole eggs thicken when frozen?
Yes, but it's typically minimal.
139
What is added to whole eggs that prevents iron sulfide from turing them grayish-green when heated?
Citric acid
140
Whole-egg substitutes, such as Egg Beaters, are made from what? How do they achieve a yellow color?
They generally contain 99% egg white, making them fat-free and cholesterol-free. They often contain beta carotene for a yellow color.
141
What should be noted about bake times when substituting egg whites for whole eggs?
Egg whites coagulate faster than yolks and, if you're not careful about reducing the bake time, baked goods may be tough, spongy, and dry.
142
Whole-egg egg substitutes may have what else added besides beta-carotene?
Dry milk solids, vitamins and minerals, gums, and seasonings.
143
Consider using what in baked goods instead of whole egg substitutes? Why?
Egg whites because they usually cost less with a substantially better flavor. You can always ad a bit of food coloring.
144
What is meringue powder?
A combination of pasteurized dry egg whites, sugar, stabilizers (starch and gums), free-flowing agents (silicon dioxide), whipping aids (cream of tartar, sodium lauryl sulfate), and flavor.
145
Pasteurized dried whole eggs, egg yolks, and egg whites are dried until how much moisture remains?
Less than 5%
146
Why can drying reduce the acceptability of eggs in certain applications?
Because it changes color and flavor.
147
How can you apply dried egg products?
Follow manufacturers instructions for reconstituting them or combine powder to other sifted, dry ingredients and add a measured amount of water with other liquids.
148
Because of their heat sensitivity, how are dried egg whites manufactured differently than dried whole eggs or dried yolks?
First, liquid whites are treated with an enzyme to remove the small amount of glucose that is naturally present in egg whites. If the glucose is not removed, dried egg whites darken through Maillard browning to an unattractive tan color during drying, storage, and baking. Once dried, egg white powder is typically held for a week to ten days in a hot room at 130ºF (54ºC). The heat pasteurizes the egg whites and improves the egg white's gel strength and whipping ability.
149
Why do pastry chefs sometimes add dry egg whites to liquid egg whites?
To increases body and improve the stability of meringue.
150
Because they are glucose free, dried egg whites are sometimes used in what?
Baked meringue shells, to minimize browning. Also frequently used in royal icing, so it dries to a glossy hard finish.
151
Egg provide many complex functions in baked goods, some of which overlap. Give an example.
The ability of eggs to bind ingredients is related to their ability to emulsify and to form structure.
152
Coagulated egg proteins in both egg whites and yolks are important ______ _______ in baked goods.
Structure builders
153
Are eggs as important as flour when it comes to structure?
Yes, sometimes more so. In fact, without eggs most cakes would collapse.
154
Besides cakes, eggs also contribute to structure in what?
Quick breads, cookies, muffins, and certain yeast breads.
155
Do coagulated egg proteins also provide thickening and gelling; a form of structure? Give examples of foods that benefit from this?
Yes, pastry cream, crème anglaise, cream pie, and custards.
156
Why are eggs considered tougheners?
Because of their ability to provide structure. They are probably the only common bakery ingredient containing significant amounts of both tougheners (proteins) and tenderizers (fats and emulsifiers).
157
The tenderizers in eggs are concentrated where?
The yolk
158
Why do the proteins in egg yolks not create the same structure as proteins in whites?
The proteins in yolk are bound as lipoproteins and do not coagulate as quickly as egg white proteins, producing a shorter, more tender structure. Added fats and emulsifiers in yolk also help.
159
Why do egg yolks contribute less toughening (less structure) than an equal weight of egg whites?
Tenderizing fats and emulsifiers in yolk.
160
Yolks, despite containing tenderizers, are classified as what?
Tougheners or structure builders. Egg yolks are not tenderizers.
161
What would happen if eggs were left out of muffins?
Traditional muffins and quick breads rely as much or more on eggs than on flour for their coarse, crumbly structure. If left out and replaced with water or milk, muffins would be more tender and have lower volume; white in color and bland in flavor. Eggless muffins taste more like sweet baking powder biscuits.
162
Why are egg yolks not considered tenderizers?
Sometimes they are, but it usually is when the yolks are compared to whole eggs.
163
Is it true that baked goods made with egg yolks instead of whole eggs are more tender? So shouldn't they be classified as tenderizers? Example.
Yes, but it is not the same as a tenderizer; they simply produce a more tender crumb than whole eggs. Add more tenderizer to a baked good and it becomes more tender. Do the same with egg yolks and the baked good toughens (just less so than if whole eggs were added). Tug of war between tenderizers and tougheners; tougheners win.
164
Eggs are unique because they are especially good at what?
Aerating, producing a relatively stable foam.
165
Foams consist of what?
Tiny bubbles of air or another gas surrounded by a liquid or solid film.
166
Examples of baked goods that rely heavily on foaming?
Angel food, chiffons, sponge, genoise.
167
The foaming power of eggs refers to how high they can be what?
Whipped
168
Do egg whites have a very high foaming power? How much?
Yes, they can whip up to 8 times their volume.
169
What happens when egg whites are whipped to their max? What if they baked?
They have extremely thin cell walls consisting of overstretched proteins. When placed in a hot oven, these proteins are likely to break and collapse.
170
Do whole eggs and egg yolks foam?
Yes, just not as well as egg whites.
171
Ranking order of foaming power for eggs.
whites>whole eggs>yolks
172
Why are eggs often added to creamed butter or shortening?
To emulsify and stabilize the mixture.
173
What care must be taken when adding eggs to creamed shortening?
If eggs are added too quickly or are too cold, the emulsion breaks.
174
My emulsion of shortening and eggs breaks. However, the addition of flour and other ingredients seems to bring it back together. Is this true?
While the subsequent addition of flour and other ingredients appears to bind the emulsion back together, a poorly emulsified batter bakes into cake that may not rise properly and that has a coarse crumb.
175
Do eggs yield a rich flavor in baked goods?
Yes
176
What would happen if egg yolks replaced whole eggs in cakes?
In a liquid shortening cake, the cake baked with eggs yolks would be richer in flavor, more yellow in color, and often more crumbly and dry. This happens because yolks are lower in moisture and higher in tenderizers than whole eggs.
177
When do baked goods become crumbly and dry?
When they are so tender and dry that they break into tiny pieces when cut or chewed.
178
In some cakes, why does direct substitution of whole eggs for yolks produce a denser, tougher product?
If water is so limited that there is much less steam produced to leaven and therefore tenderize a cake.
179
Why should you not use aluminum bowls, beaters, or saucepans when working with egg mixtures?
The eggs discolor aluminum, and worse, aluminum discolors egg mixtures to a dull gray.
180
How do eggs contribute to Maillard reaction?
They contain protein and a small amount of glucose.
181
Are the yellow-orange carotenoids in eggs yolks antioxidants?
Yes
182
What carotenoid in eggs is thought to decrease the risk of macular degeneration (a severe loss in vision of people over 50)?
Lutein
183
Hens today are bred and fed to produce eggs that are lower in what?
Fat and cholesterol.
184
What in eggs interferes with starch retrogradation?
Fats, emulsifiers, and proteins.
185
What is eggs drys to a glossy brown film when egg wash is applied to the surface of doughs?
Egg proteins
186
Egg wash can be made with eggs diluted in water or, for additional browning, eggs diluted with ______.
milk
187
How do eggs serve as edible glue?
They help nuts, seeds, spices, and sugar crystals adhere to baked goods. Eggs also allow batters to adhere to foods that are fried.
188
The mark of a good sorbet is what?
Soft texture, free of large ice crystals.
189
What do egg whites do for sorbets?
Helps sorbets stay smoother during storage.
190
Besides keeping sorbets smoother during storage, how else do egg white affect them?
Sorbets made with added egg white have a milder, less intense flavor than ones made without. Because white are aerated, it also makes the sorbet lighter and airier. This also creates a paler color.
191
If adding egg whites to sorbets, what should you be sure of?
Egg whites are pasteurized.
192
Why does adding extra eggs make brownies cake like?
Eggs provide aeration, and cake-like brownies are lighter than fudge ones. Butt the added lightness from cakey brownies is likely from the moisture in eggs. Moisture converts to steam when heated, and steam is very powerful leavening gas, important in lightening texture of baked goods. The moisture in eggs also allows the starch fully gelatinize, and gelatinized starch is essential for cake-like crumb.
193
What are two different ways people like brownies?
Dense and fudge or light and cakey.
194
What do fats, emulsifiers, and proteins in eggs do to sugar and ice crystallization?
They interfere, helping produce velvety smooth texture in icings, confections, and frozen desserts.
195
Ice cream that contains added egg yolks for creamy smoothness and richness.
French-style
196
Whole eggs contain how much moisture?
Approximately 75%
197
Remember that baking involves balancing moisteners with driers. If eggs are increased is a formula, what must be decreased?
Other liquids such as milk or water.
198
Does adding eggs increase moisture and moistness? Why?
No, because eggs also contain structure-building proteins, the use of eggs often makes a product taste tougher and drier.
199
Can eggs increase softness in raw dough? Explain.
Yes, they interfere with gluten development in raw dough, even as they provide structure of their own once baked. Gluten bonds with other gluten proteins, and egg fats, emulsifiers, and proteins interfere with this bonding.
200
When making brioche dough, when should eggs be added? Why?
It can be helpful to without some eggs until the dough has been well mixed. This way, gluten can develop properly before eggs have a chance to interfere with the process.
201
Rich, yeast-raised dough high in eggs, sugar and butter.
Brioche
202
A basic egg custard consists of what?
Egg, milk or cream, sugar, and flavoring.
203
Examples of egg custards.
Creme caramel, creme brûlée, creme anglaise.
204
Name baked goods with a custard base.
Pumpkin pie, cream pie, bread pudding, rice pudding, pastry cream, quiches, cheesecakes.
205
A properly cooked custard based product is described as what?
Moist, tender gel or a smooth, creamy sauce.
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A description of the process of egg coagulation.
As eggs are heated, proteins in yolks and whites denature and unfold. The unfolded proteins move through the liquid and bond, or aggregate, with one another. The more eggs are heated, the more proteins aggregate, and the tighter, firmer, and more rigid the preteen network becomes. Eventually, proteins over coagulate, shrinking and squeezing out liquids, much like a sponge shrinks and releases water when it is wrung.
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Protein coagulation is sometimes called what?
Protein aggregation.
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Properly aggregated proteins form what?
Strong, yet often flexible network that traps water and other liquids.
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Over-coagulation is sometimes called what?
Curdling
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Curdling results in what?
Weeping or syneresis, where bits of tough gel float in pools of squeezed out liquid.
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Often, water that is released from over-coagulated proteins evaporates, or it is absorbed by other ingredients. Explain.
This happens in cakes and other baked goods, where gelatinizing starches absorb water that is squeezed out of over coagulated egg proteins. The protein network and the cake, however, still shrink to a dry, rubbery toughness.
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While heat is the most common means of coagulating proteins, they are also coagulated by what?
Acid, salt, freezing, whipping, and drying.
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How does sugar "cook" egg yolks?
When sugar is placed on egg yolks and not stirred in, the yolks gel and appear to cook. Sugar, being hygroscopic, pulls water from the egg yolks ( recall that yolks are about 50% water) and dries them out. Without water, proteins in yolk are closer together and quickly aggregate, as if heat was applied. To avoid this, never add sugar to yolks without stirring the two together. The yolks will thicken, but they will not solidify.
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Proteins in an undiluted egg properly coagulate at what temp? What if it's diluted?
160ºF (70ºC), dilute the egg with milk, water, or other ingredients, and the coagulation temperature increases.
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The coagulation temperature for most vanilla custard sauce formulas is what?
180º-185ºF (82º-85ºC)
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Why do diluted egg proteins denature at a higher temperature?
The dilution with milk, sugar, and cream makes it more difficult for the proteins to bump into on another and bond. This reduced the risk of over coagulation.
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When bonding of diluted egg proteins eventually occurs, what should be expected in the end product?
Expect a softer, more tender product when the additional liquid is trapped in the coagulated protein network.
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What happens when egg proteins coagulate too quickly? Example?
They don't unfold properly and are less likely to thicken or gel as well. Creme anglaise, cooked over high heat, is more likely to curdle and burn and less likely to fully thicken.
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Egg yolks coagulate at what temp?
150º-160ºF; 65º-70ºC
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Egg whites coagulate at what temp?
140º-150ºF; 60º-65ºC
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Why do egg yolks aggregate at a higher temp?
Egg yolk proteins are lipoproteins, bonded to fats and emulsifiers. The fats and emulsifiers make it more difficult for proteins to aggregate.
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Ranking the parts of an egg from highest to lowest in the rate of over coagulation.
Egg white>whole eggs>egg yolks
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Besides diluting protein molecules, sugar slows what? Explain.
Egg protein coagulation in custards and baked goods by preventing the proteins from unfolding. If proteins are slow to unfold, they will be slow to coagulate, unless temperatures are raised. This means sugar helps prevent curdling. It is why quiches, which are essentially egg custard made without sugar, are more apt to curdle and weep than egg custard itself.
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What is tempering?
The careful addition of one ingredient to another when two ingredients start at different temperatures.
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Why is tempering important with eggs?
If eggs are added directly to hot liquid, het from the liquid prematurely cooks the eggs, and bits of coagulated egg form in the mixture.
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Besides tempering hot liquid into eggs, what is another way to protect the eggs from coagulating when tempering?
Adding another ingredient like sugar that will help dilute the eggs further.
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Water baths rarely exceed what temperature?
Even when the oven is set at 325ºF (165ºC) or more, water baths rarely exceed simmering (180º-190ºF; 82º-88ºC).
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How do water baths helps baked goods such as custards?
This slows the process and evens out baking so that the outside of the custard does not become tough, rubbery, and curdled before the inside bakes.
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How high should a water bath go?
No higher than half way up the sides of your dish.
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By slowing the coagulation, sugars slow the formation of egg structures (sugars also slow the formation of gluten and starch structures) . If enough sugar is present, what happens?
Coagulation is stopped completely, and the baked good will remain raw, even after extended baking.
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Do lipids tenderize custards much as they tenderize baked goods? Explain.
Yes, like sugars, lipids (fats, oils, and emulsifiers) interfere with coagulation of egg proteins and so tenderize custards. Lipids slow coagulation by coating egg proteins, just as they tenderize gluten structure by coating gluten proteins.
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Custards make with a high amount of lipids--from either cream or e.g. yolk--are more than just soft and tender. What are they?
Cream and yolks provide an added dimension, a smoothness and creaminess not seen in custards made without these ingredients.
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Does acid speed up egg coagulation? How does this affect baking times?
Yes, acids lower the temperature of coagulation. It could come from lemon or other fruit juices, raisins or other fruits, or cultured dairy products. Be sure to carefully monitor baking times when using acidic ingredients.
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Does starch increase the temperature of egg coagulation?
Yes, by interfering with the process.
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Is pastry cream essentially custard sauce with added starch? Why can custard sauce not handle the same temperatures as pastry cream?
Yes, but custard sauce could not handle temperatures over 185ºF (85ºC) without curdling. However, pastry cream has added starch which interferes with egg coagulation. This allows pastry cream to be boiled without curdling.
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Vanilla custard sauce is easily curdled. Can it be saved after being overcooked?
As long as the curdling wasn't too excessive you can smooth it in a blender or food processor. There will be differences, however, between a saved sauce and a properly made one.
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What notable differences are there between a properly made vanilla custard sauce and a saved one?
Over cooking will create a deeper egg flavor and deepen the yellow color. The extent of blending will increase the airiness of the sauce, making it slightly foamy, at least initially. Finally, a saved sauce is typically thicker than the one not overcooked. This is partly because the air worked into the sauce but also because egg proteins are fully cooked and coagulated.
238
What does calcium in hard water and in dairy do to the coagulation of eggs?
Strengthens the coagulation of egg proteins.
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How could you replace dairy with water in a vanilla custard sauce?
Using hard water to replace milk restores much of the lost gel strength if using regular water, but not the rich dairy flavor.
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What do protease enzymes do to egg proteins?
They break down egg proteins much as they break down gelatin protein.
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Try to make a baked custard using uncooked pineapple. What happens? How is the remedied?
The pineapple contains active proteases that will not allow the custard to set. Cook the pineapple first, inactivate the enzymes, and the intact proteins in the custard will coagulate.
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Does stirring eggs as they are heated affects coagulation? Examples using baked custard and custard sauce.
Yes, compare baked egg custard to stirred vanilla custard sauce. Custard sauce is typically made with egg yolks and part heavy cream, while baked custard is made whole eggs and whole milk. From this alone, you would expect a softer set from the custard sauce. Yet, the stirring is a striking difference in the procedure. Constant stirring keeps egg proteins from aggregating into a solid mass, so the sauce thickens instead of forming a firm solid (and, if not stirred, custard sauce would burn the bottom of the pan).
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What is meringue?
Egg white whipped with sugar.
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What is meringue used for?
Lightness and volume in mousses, soufflés, angel food and sponge cakes, and icings. It can also be baked in a low temperature oven for macaroons, cake layers, and tartlet shells.
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Meringue could not form without the unique combination of proteins that are present in egg white. What are these four proteins?
Ovalbumin, conalbumin, globulin, and lysozyme work together for maximum foaming power and stability.
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As egg whites are whipped, what two things happen simultaneously? Continue explaining the process.
Air bubbles are beaten into the liquid, and certain egg proteins denature, or unfold. The unfolded proteins quickly move through the liquid to the surface of the bubbles. Once there, neighboring proteins bond or aggregate around the bubbles, forming a filmy network. Surrounded by these strong, flexible films, air bubbles are less likely to collapse, so more bubbles can be beaten in, even as the walls of the film thin out.
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How is whipping a meringue similar to adding heat to an egg?
They both cause protein molecules to unfold and bond together, forming a type of structure.
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Stable meringue is what?
Firm yet flexible and resilient, so it can stand up to folding, baking, and piping.
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Often, do the very things that increase stability decrease volume and tenderness?
Yes
250
Does sugar reduce volume and slow whipping? How should sugar be added in a common meringue?
Yes, this is why sugar should be withheld until the egg white have already begun to foam.
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Does sugar stabilize meringues?
Greatly, even as it slows whipping and decreases volume slightly.
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For a common meringue, sugar stabilizes best if added _______, and only if the proper amount is _______.
slowly, added
253
A useful way to classify meringues is how?
The ratio of sugar to egg whites.
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Two main classifications of meringues when using ratios of sugar to egg whites?
Hard and soft.
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Ratio for hard meringues.
2 parts sugar: 1 part egg by weight
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Ratio for soft meringues.
1 part sugar: 1 part egg whites by weight
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Difference between hard and soft meringue.
Denser and less tender than soft meringues, but more stable and can easily be piped.
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Soft meringues should be used for what?
Light-texture topping on lemon meringue pie, but only if it's going to be served fairly soon.
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Hard meringues can be used for what?
Baked torte ayers or for baked meringue shells or cookies.
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What meringue is more common in the bakeshop? Why?
Hard meringue because it's more stable.
261
Why should sugar crystals be added slowly to meringue?
Provide time for them to dissolve and not weigh down the foam. In addition if sugar is added too quickly, protein molecules may not unfold properly. The result is a softer meringue or whites that will not whip.
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How does sugar stabilize meringue? Two ways.
By slowing down the unfolding and aggregation of protein molecules. This aids in stability because it protects against over whipping. Also, ass sugar dissolves in meringue's liquid film, sugar forms a thick, viscous syrup that is slow to drain. This protects the bubbles from collapse. The sugary syrup also adds a satiny sheen.
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What do undissolved sugar crystals do to meringue?
Weigh down meringue, weakening it. Once baked, these crystals attract moisture and sometime forms unattractive beads of syrup.
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How do you minimize beading and volume loss in meringues?
Sift sugar first, and add it slowly, allowing it to dissolve between additions. Otherwise, use superfine or another finer grind of sugar, so sugar dissolves faster.
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What do lipids do to aeration of meringue?
They interfere. Depending on the type and amount, lipids either slow down or completely prevent it.
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What lipid prevents aeration more than others?
Egg yolk lipids, more so than shortening or vegetable oil can prevent whites from whipping.
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How do lipids interfere with aeration?
By coating proteins, preventing them from unfolding and aggregating. But they also compete with proteins for a spot at the foam's bubble surface. Since lipids themselves cannot form a strong, cohesive, network like egg proteins, lipid-coated bubbles expand rapidly, only to collapse.
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How can you avoid problems with fats, oils, and emulsifiers when whipping meringue?
Be sure to use a clean bowl, carefully remove any stray bits of yolk from your whites, and stay away from plastic bowls and utensils, which absorb fats and oils and cannot easily be cleaned.
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How does acid stabilize meringues?
By lowering pH.
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Most common acid used for meringues? List others.
Cream of tartar is most common, but lemon juice and vinegar also stabilize.
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When should acid be added? How does it affect meringue aesthetically and texturally?
Early on. Whipping might take longer, but protein networks that form will be flexible and stable against over-whipping, folding, pipping, and baking. The meringues will also be whiter.
272
Will egg white right out of the fridge whip well?
No, ideal temp is about 70ºF (20ºC).
273
Can any of the three meringues be soft or hard?
Yes
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What are the three meringues?
Italian, French, Swiss
275
How does a swiss meringues method affect meringues?
Warming the sugar and whites dissolves the sugar and undoubtedly has an effect on the unfolding of egg proteins.
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Good temp for swiss meringue.
110º-120ºF (40º-50ºC)
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Because frozen egg whites have already been heated to pasteurize, what care must be taken when using them to make a swiss meringue?
Warm the whites just until the sugar dissolves, then immediately remove from heat.
278
What meringue is essentially cooked?
Italian
279
Hot sugar syrup is heated to what temp for Italian meringue?
248º-250ºF (120-121ºC)
280
Italian meringue is the most stable meringue, but what's the tradeoff?
Lowest volume and the most dense, least tender mouthfeel.
281
How can you warm egg whites without waiting?
Warm in a water bath that's just below simmering and stir constantly.
282
What whips better, old or new egg whites? Which is more stable and lasts longer? Why?
Thin, older whites whip more easily and to a higher volume than thick, fresh whites. Yet, once whipped, the foam from thin whites is less stable, because the liquid film drains more easily form the bubbles.
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A good rule of thumb for better stability.
Use fresher eggs for meringues and older ones for baking.
284
Are both under whipped and over whipped egg whites unstable? Explain.
Yes
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Why are under whipped egg whites unstable?
If under whipped, proteins are not fully aggregated to form a strong film. In time, they will weep.
286
When whipped too quickly or for too long, proteins what? Explain.
Denature and aggregate extensively, and the protective film that surrounds each air bubble becomes overstretched and rigid. The whites eventually collapse, forming tightly bonded, inflexible clumps of protein floating in squeezed-out liquid. In other words, too much whipping has a curdling effect on egg protein structure similar to the effect of too much heat. Over whipped whites should be discarded.
287
Whip egg whites no faster than what?
Medium-high speed
288
Should you try to time your meringues so they are used immediately?
Yes
289
Do copper and salt affect stability of meringues?
Yes
290
How does copper increase meringues stability?
It works the same way cream of tartar does, that is, it improves flexibility of a protein network so that it is stable against over whipping, folding, piping, and baking. With copper, time particles of copper and whipped into the whites each time the whisk hits the bowl.
291
Egg whites whipped in copper bowls have what color?
Slight golden
292
Does salt decrease meringue stability?
Yes
293
Do the size of the wires or whisks affect stability?
Yes, larger ones produce less stable air bubbles than thinner ones. It's best to use a finer piano whisk for whipping whites.
294
Receiving and storing eggs and egg products: checking temp
Check temp of whole shell eggs by breaking one or two into a small cup and immediately measuring the temperature. Eggs should be 45ºF (7ºC) or below, by law.
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Receiving and storing eggs and egg products: Freshness
Evaluate one or two for freshness. Check for cleanliness of shell, thickness of white and yolk, and odor.
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Receiving and storing eggs and egg products: Storage
Refrigerate or freeze immediately upon delivery. Store dry egg products at room temp in a cool dry area. 38-40ºF for shell eggs with 75-85% relative humidity.
297
Receiving and storing eggs and egg products: unopened refrigerated liquid egg products.
Can be held for up to 12 weeks, if kept at or below 40ºF. Once opened, use within a few days. Label cartons with thaw dates...FIFO.
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Receiving and storing eggs and egg products: treating opened thawed frozen liquid egg products.
Treat like refrigerated products. Refrain from refreezing unused product, since it is freeing and thawing that courses the most damage to frozen foods, including e.g. products.
299
What is salmonellosis?
One of the most common food borne infections. An estimated 118,000 illnesses per year in the US are cases by the consumption of eggs contaminated with salmonella. Symptoms include diarrhea, fever, intense abdominal pain, and vomiting. Mild cases often last two or three days.
300
Can salmonella be completely eliminated from raw foods of animal origin?
No, it must be carefully controlled by the food preparer.
301
Should you discard eggs that have even the slightest cracks or a strong off odor?
Yes
302
Why shouldn't you crack and pool eggs together for later use?
They are susceptible to bacteria.
303
Should you crack eggs into bowls with other ingredients?
No, crack in separate container and inspect.
304
When breaking eggs, should shell come into contact with egg contents?
No, although washed and sanitized the shells subsequently pick up dirt or microorganisms.
305
Should you thaw frozen egg whites at room temp?
No
306
Minimum cook time for shell eggs.
Cook or hold at 140ºF for at least 3.5 minutes.
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How to thaw frozen egg products.
Under refrigeration or under cold running water.
308
How to use dried eggs.
Blend with dry ingredients or reconstitute. Wait 1 hour for yolks and 3 hours for whites in refrigerator. This allows egg to hydrate properly.
