Types[edit | edit source]
Chicken eggs are standard, and the term "egg" without any other qualifiers when used in a recipe most likely refers to chicken eggs. Duck, goose, quail, and ostrich eggs (the largest edible bird eggs in the world) are occasionally used as gourmet ingredients. Reptile eggs, particularly turtle eggs, are sometimes eaten as well.
Chicken eggs of different colors
Smallest to largest: quail, jumbo chicken, and duck eggs
Clockwise from top: turkey, goose, and duck eggs
Smallest to largest: quail, chicken, and ostrich eggs
An ostrich egg
Composition[edit | edit source]
For the purposes of cooking, chicken and other bird eggs consist of the following major parts; all but the shell are edible:
- Shell: hard outer covering consisting largely of calcium carbonate
- Membrane: thin, flexible layer between the shell and the white
- White: clear, viscous fluid consisting primarily of albumen protein and water
- Yolk: yellow center, consisting of fats and proteins
- Chalaza: fibrous white pieces connecting the yolk to the shell
Sizing[edit | edit source]
Many countries have a standardized sizing system for chicken eggs, though the terminology used by each system is different and may not agree with the others. So, for normal recipes, it is best to avoid specifying egg size. In general, most recipes use "standard" eggs unless otherwise specified, which correspond to USDA size large and EU size M; these standard eggs tend to weigh about 50–60 g each out of shell.
EU weight standard[edit | edit source]
EU eggs are specified as per-egg weight ranges, plus a per-100 minimum.
|SIZE||PER EGG||PER-100 MIN|
|XL (very large)||73 g and more||7.3 kg|
|L (large)||63 to 73 g||6.4 kg|
|M (medium)||53 to 63 g||5.4 kg|
|S (small)||under 53 g||4.5 kg|
USDA weight standard[edit | edit source]
USDA eggs are specified as the minimum weight of a dozen.
|SIZE||MIN NET PER DOZEN||CONVERTED TO MIN GRAMS/EGG|
|Jumbo||30 ounces||70.9 g|
|Extra Large||27 ounces||63.8 g|
|Large||24 ounces||56.7 g|
|Medium||21 ounces||49.6 g|
|Small||18 ounces||42.5 g|
|Peewee||15 ounces||35.4 g|
Storage and processing[edit | edit source]
Eggs are most often procured whole, in their shells. Whole eggs may be stored at room temperature or in the fridge, depending on how they are processed. Chicken eggs are covered in a protective layer called the cuticle, which helps prevent bacterial contamination and subsequent spoilage. Eggs in the European Union and many other places leave this layer intact, and these eggs can be stored at cool room temperatures for up to several weeks. However, some regions such as the United States have most commercially-available eggs undergo a washing process that strips the protective cuticle from the egg, thereby requiring storage in the refrigerator to prevent spoilage. Make sure to check the recommended storage conditions for your eggs in the region you purchase them in.
Eggs may also be sold as "egg products", which refers to eggs that are removed from their shells for processing. The processing of egg products includes breaking eggs, filtering, mixing, stabilizing, blending, pasteurizing, cooling, freezing or drying, and/or packaging. Egg products include whole eggs, whites, yolks and various blends with or without non-egg ingredients that are processed and pasteurized. They may be available in liquid, frozen, or dried forms.
Freezing[edit | edit source]
For use in baking, frozen eggs can be used in place of fresh ones if used as soon as thawed soft. Drop them into boiling water that has been removed from the heat source, letting them remain until the water is cold. They will be soft all through and beat up as well as fresh eggs do.
Safety[edit | edit source]
Food-borne illness[edit | edit source]
Raw eggs may carry Salmonella bacteria contamination, and they should be avoided by those with weak or undeveloped immune systems, such as the elderly, infirm, or pregnant. The bacteria can be killed by fully cooking eggs.
Spoilage[edit | edit source]
Fresh eggs will eventually spoil, though the timing depends on their degree of processing and storage conditions. When eggs become rotten, the yolk will turn green and the egg will emit a sulphurous smell when broken.
It is possible to test an egg for freshness, prior to breaking. To do so, drop the egg into a cup of water. A fresh egg will sink to the bottom of the cup, while an older or rotten egg will float towards the surface due to the buildup of gases within the shell. For extra caution, eggs can be broken into a cup one at a time before adding to a mixture—this allows for the bad ones to be easily detected and rejected without ruining the rest of the batch.
Although deemed offensive by most Western palates, fermented eggs are considered a delicacy by some in China, when prepared using a special method which includes letting them sit for three months to age. However they can be considered dangerous.
Explosion[edit | edit source]
Due to the formation of steam inside the shell, whole eggs can explode if cooked above boiling temperatures. Never microwave a whole egg.
Techniques[edit | edit source]
Peeling eggs[edit | edit source]
The membrane and shell of fresh chicken eggs cling to the egg white when it is hard-boiled, making it nearly impossible to de-shell/peel. This is a common problem with an easy solution. Simply add a couple tablespoons of salt to the water when you boil your eggs and your eggs will peel easily.
Separating eggs[edit | edit source]
The traditional way to separate an egg (into yolk and white) is to crack the egg into two roughly equal parts, and pass the yolk from one half of the shell to the other, letting the white fall into a bowl below. A simpler way is to form a slack fist with one hand, crack the egg into it, and let the white run through your fingers into a bowl. It's a bit unnerving at first, but you soon develop a feel for the yolk. And if you are using the yolk for mayonnaise for example, the heat from your hand will helpfully warm it. Don't forget to wash your hands first!
Use[edit | edit source]
Eggs are frequently used to bind other ingredients together, trap air in the food, or create an emulsion. Depending on the intended product, only the egg yolk, only the egg white, or both may be used for preparing a food. In most recipes, a whole egg may be replaced with two egg whites to make a dish lower in fat and cholesterol.
The primary cooking techniques for eggs are:
Egg wash is also often used in baking and battering.
Alternatives[edit | edit source]
Some people can't eat eggs because of allergies or because of ethical convictions about egg production. People who have allergies are usually allergic only to the egg whites, due to the much higher protein content of the white as opposed to the yolk (the white is nearly pure protein, while the yolk is mostly fat.) Often people are only allergic as children and later grow out of it. People with ethical convictions against eggs include vegans and some vegetarians.
All these people must use egg substitutes if they wish to eat anything like an egg. No egg substitutes are perfect replacements, and most are very application-specific, but in many recipes an acceptable finished product can be achieved. Common substitutes from scratch include cornstarch (1 Tablespoon dissolved in 3 Tbsp. of warm water per egg) or soy flour (1 Tbsp. + 2 Tbsp. water). Many use ready-made substitutes such as Ener‑G brand egg replacer, which is largely made from potato starch. Tofu plus seasonings are often used as a substitute for scrambled eggs.
For baking, shredded flax or chia seeds (8 g/1 Tbsp. stirred into 45 ml/3 Tbsp. of water and allowed to stand for 20 minutes) can be used in doughs and batters that are dark enough that the dark-colored seeds won't be visible. For light-colored doughs and batters, 45 ml/3 Tbsp. of aquafaba or 1 Tbsp. cornstarch dissolved in 3 Tbsp. warm water is recommended.
Recipes[edit | edit source]
For a full list of recipes using eggs, see egg recipes or browse below: