Eggs, from A to Z
Plain-language definitions for the words used in egg nutrition, cooking, production and safety, with regional differences clearly identified.
Incorporating air into eggs by beating or whisking. The trapped bubbles can add volume to foams, cakes, soufflés and omelettes.
Foaming and aerationThe pocket of air between the shell membranes at the broad end of an egg. It usually grows as an egg loses moisture during storage.
Storage and freshnessThe egg white: mostly water and proteins surrounding the yolk. Thick and thin albumen are normal parts of a fresh egg.
Yolk and white nutritionA water bath that surrounds a dish with gentle, even heat. It helps custards set without curdling or cracking.
Heat and thickeningEggs from hens kept indoors but not in cages. Space, enrichment and labelling rules differ by jurisdiction.
Compare housing systemsA small pale spot on the yolk where an embryo could begin developing if an egg were fertilised and incubated. In an unfertilised egg it is also called the germinal disc.
Egg anatomy questionsA broad label meaning hens are not housed in cages. It does not necessarily mean outdoor access, and legal standards vary internationally.
International label guideShining light through an egg to inspect internal quality without breaking the shell, including cracks, air-cell size and some inclusions.
Grading and inspectionOne of two twisted cords of egg white that help hold the yolk near the centre. A visible chalaza is normal and safe to eat.
Expanded answerAn essential nutrient involved in cell membranes, liver function and nervous-system signalling. Egg yolks are a concentrated dietary source.
Egg micronutrientsThe joining of unfolded egg proteins into a network as they heat. This changes liquid egg into a soft or firm set.
How eggs setAn egg cooked gently in water just below boiling, either in its shell or in a small covered dish. Exact usage varies by recipe and country.
Cooking methodsKeeping a food within its required chilled temperature range through storage and transport. Egg refrigeration practice varies internationally.
Regional storage guidanceA protein source containing all nine essential amino acids. Eggs qualify, though overall dietary variety still matters.
Protein in eggsThe transfer of harmful microbes from a food, surface or hand to another food. Handwashing and cleaning utensils after raw egg contact reduce the risk.
Safe handlingA soft cluster of coagulated egg in scrambled eggs or an omelette. Lower heat and steady movement usually create smaller, tender curds.
Scrambled eggs methodA thin natural coating over the shell that helps block pores. Often called the bloom; washing practices differ between countries.
International processingThe unfolding of egg proteins through heat, whisking, acid or salt. It precedes the new bonds that set eggs or stabilise a foam.
The science of eggsCholesterol present in food. It is distinct from cholesterol measured in blood, and individual responses to intake vary.
Eggs and cholesterolAn egg containing two yolks, usually because two yolks were released close together. It is commonest in young hens and is normally safe to eat.
Common questionsAn immune reaction to egg proteins, most often in the white but potentially also in the yolk. It is different from an intolerance and needs individual medical advice.
Allergy guidanceEgg removed from its shell and processed for food use, including liquid, frozen or dried whole egg, whites and yolks.
Egg product formatsDispersing tiny droplets of one liquid through another that would normally separate. Egg yolk lecithin helps stabilise mayonnaise and sauces.
EmulsifyingA network of egg-white proteins surrounding air bubbles. Clean equipment and controlled whisking help create a stable foam.
Foams explainedA production claim generally indicating some outdoor access. Stocking density, access duration and other requirements differ between countries.
What labels meanA softly set, usually unbrowned omelette rolled or folded into a smooth oval, with small tender curds inside.
French omelette recipeA regulated quality classification based on characteristics such as shell condition and internal quality. A grade is not the same as egg size.
Grades by regionAn informal term for a yolk cooked to a thick, spreadable consistency between runny and fully firm.
Doneness guideA carotenoid pigment found in egg yolk and many plants. Along with zeaxanthin, it accumulates in the retina of the eye.
Vitamins and compoundsA tiny piece of tissue sometimes found inside an egg. It is not an embryo and may be removed for appearance; discard the egg if it also smells or looks spoiled.
Spots and egg qualityA foam made by whipping egg whites, usually with sugar. French, Swiss and Italian methods differ in how the sugar and heat are applied.
Meringue recipeA regulated production label covering feed and husbandry standards. The precise rules and certifying marks depend on the country.
Organic systems comparedThe date eggs were packed, sometimes shown directly and sometimes encoded. It is distinct from a best-before, sell-by or expiration date.
Read an egg cartonA controlled heat treatment designed to reduce harmful microorganisms while limiting changes to the food. Pasteurised shell eggs and egg products are not available everywhere.
Pasteurisation explainedA label associated with hens using vegetated outdoor areas. It is not defined consistently everywhere, so check the relevant standard or certification.
Housing claims comparedA code on an egg or carton that can identify production method, country and farm or packing site, depending on the regional system.
Traceability by regionA group of bacteria that can cause foodborne illness. Risk varies by country and production system; handling and cooking guidance should follow local authorities.
International safety guidanceThe feeling of fullness after eating. Protein-rich meals can support satiety, but the whole meal and the individual both matter.
Eggs, satiety and weight lossAn essential trace mineral that contributes to antioxidant enzymes and thyroid function. Eggs provide a useful amount, which varies with feed.
Minerals in eggsTwo thin layers just inside the shell that provide a physical barrier and form the air cell at the broad end.
How an egg formsA weight band such as small, medium, large or extra-large. The gram ranges behind those names are not identical worldwide.
International size converterGradually mixing hot liquid into eggs so their temperature rises slowly, reducing the chance of lumps or scrambling.
Thickening without curdlingThe records and codes used to follow eggs through farming, packing and distribution, supporting quality control and recalls.
Farm-to-carton journeyThe transparent membrane enclosing the yolk. It weakens with age and heat, which is one reason older yolks break more readily.
Egg structure and scienceThe yellow centre of an egg. It contains fat, protein and most of the egg’s choline, vitamin D and several other micronutrients.
Yolk nutritionA carotenoid pigment in yolk and plant foods that, with lutein, is present in the macula of the eye.
Egg micronutrientsA definition is a starting point. Where a term involves health, safety or regional labelling rules, follow the linked guide for context and check the authority responsible where you live.