Pasteurized whole eggs: properties, uses, advantages, disadvantages, safety

Pasteurized whole eggs are an egg product generally obtained from hen's eggs (Gallus gallus domesticus) that are removed from their shells, with the egg white and yolk retained together, mixed and subjected to a controlled heat treatment designed to reduce pathogenic microorganisms without cooking the product.

They are normally supplied as a homogeneous yellow to orange-yellow liquid, ready for accurate dosing and use in food manufacturing. Compared with shell eggs, pasteurized whole eggs offer greater standardization, convenience and microbiological control and are widely used by the foodservice and food-processing industries. USDA FSIS defines basic egg products as whole eggs, whites, yolks and blends that may undergo breaking, filtering, mixing, pasteurization, cooling, freezing, drying and packaging.

Description

Pasteurized whole eggs normally consist of egg white and yolk in approximately the proportions naturally present in the whole egg, after removal of the shell.

A typical hen's egg is composed mainly of albumen and yolk, together with the shell. Reference composition data show that whole egg is predominantly water, followed by protein and fat.

After breaking, the yolk and white are combined and mixed to produce a uniform liquid product. Pasteurization applies a carefully controlled combination of temperature and time sufficient to achieve the required microbial lethality while preserving as much as possible of the egg's technological properties.

There is no single universal time-temperature combination applicable to every egg product. Processing conditions depend on factors such as product composition, solids content, viscosity and the processing system. In the European Union, Regulation (EC) No 853/2004 requires liquid egg obtained after breaking to undergo processing as quickly as possible to eliminate microbiological hazards or reduce them to an acceptable level.

In the United States, egg products distributed for consumption are subject to USDA FSIS requirements under the Egg Products Inspection Act, and pasteurization is the principal lethality treatment used for liquid egg products.

Pasteurization must be distinguished from cooking: properly pasteurized liquid whole egg retains many of the functional characteristics of raw egg and can still be used in doughs, batters, creams, sauces and other formulations.

Production process

Industrial production normally includes several stages:

• selection of suitable eggs;

• inspection of shell integrity and hygienic condition;

• mechanical breaking;

• separation of the shell from the edible contents;

• collection of yolk and albumen together;

• filtration to remove possible shell fragments or membranes;

• mixing and homogenization;

• pasteurization or another validated lethality treatment;

• rapid cooling where required;

• hygienic packaging;

• refrigerated, frozen or otherwise validated storage according to the specific product.

These operations are consistent with the processing steps described by USDA FSIS for commercial egg products.

In the EU, liquid egg that is not processed immediately after breaking must be held under controlled temperature conditions, and egg products that have not been stabilized for storage at room temperature must be chilled appropriately under the requirements of Regulation (EC) No 853/2004.

Pasteurization conditions are selected to balance microbiological safety and technological functionality. Excessive heat can increase protein denaturation and alter viscosity, foaming, emulsification or coagulation behaviour, which is why industrial pasteurization is carefully controlled.

Main substances contained

Pasteurized whole eggs are a complex food matrix composed primarily of water, proteins and lipids.

The main naturally occurring components are:

• Water: the quantitatively predominant component, approximately 77% in reference whole egg composition data.

• Protein: approximately 12.4 g per 100 g in the reference data. These proteins originate from both the albumen and yolk.

• Lipids: approximately 8.7 g per 100 g, located predominantly in the yolk.

• Phospholipids: characteristic components of egg yolk, including phosphatidylcholine and other compounds with important emulsifying properties.

• Cholesterol: naturally present primarily in the yolk.

• Carbohydrates: present only in small amounts.

• Minerals: including phosphorus, sodium, potassium, calcium, iron, zinc, magnesium and selenium.

• Vitamins: including vitamin A, riboflavin, folate and other micronutrients naturally present in eggs.

• Natural yolk pigments: responsible for the yellow to orange colour of the product.

Reference whole-egg composition data report approximately 77.1 g water, 12.4 g protein and 8.7 g fat per 100 g.

When the ingredient is described simply as “pasteurized whole eggs”, these are the components naturally associated with egg. Salt, sugar, preservatives, stabilizers or other additives should not be assumed to be present unless they are specifically declared in the formulation. USDA FSIS notes that commercial egg products may be produced either plain or with additional ingredients depending on the product.

Identification data and specifications

In the European Union, egg products fall under the specific hygiene requirements for food of animal origin established by Regulation (EC) No 853/2004. In the United States, USDA FSIS regulates processed egg products under the Egg Products Inspection Act and 9 CFR Part 590. In the UK, eggs and egg products are specifically recognized in official allergen-labelling guidance.

Indicative nutritional values

These figures are indicative whole-egg composition values rather than mandatory specifications for every commercial pasteurized whole-egg product. Actual composition may vary according to the eggs used, product standardization and the possible presence of additional ingredients. Reference composition data confirm the predominance of water, protein and fat in whole hen's egg. USDA FoodData Central also lists pasteurized whole egg as a specific food category within its food-composition database.

Nutritional and technological properties

Pasteurized whole eggs are a nutrient-dense food ingredient and provide primarily high-quality protein and fat.

Egg proteins provide essential amino acids and also have important technological properties. The yolk contains lipoproteins and phospholipids with strong emulsifying capacity, while albumen proteins contribute particularly to foaming and heat-induced structure formation.

From a food-technology perspective, whole egg can perform several functions simultaneously:

• emulsifying;

• binding;

• structuring;

• foaming;

• thickening;

• contributing natural colour;

• contributing flavour and mouthfeel;

• improving tenderness and structure in baked products;

• coagulating during heating.

Pasteurization may cause limited modification of protein structure, but commercial processes are designed to retain the functional properties required for food applications while achieving the necessary microbial reduction. USDA FSIS specifically notes that pasteurization is intended to destroy harmful bacteria without cooking the egg product.

Food uses

Pasteurized whole eggs are widely used in both foodservice and industrial food production. USDA FSIS specifically identifies liquid egg products as common ingredients in commercially prepared foods.

Typical applications include:

• cakes;

• biscuits and cookies;

• brioche and enriched doughs;

• sponge cakes;

• breads and other baked products;

• fresh pasta and egg pasta;

• creams and custards;

• desserts;

• ice cream;

• mayonnaise and sauces;

• omelettes and scrambled-egg preparations;

• fillings;

• savoury preparations;

• pastry products;

• industrial formulations requiring precise egg dosing.

One of the main industrial advantages is that egg can be handled as a standardized liquid ingredient, eliminating the need to break large numbers of shell eggs manually.

The product can be dosed by weight or volume and facilitates more consistent formulation from batch to batch.

Advantages

• Provides high-quality protein.

• Naturally contains lipids, phospholipids, vitamins and minerals.

• Provides important emulsifying, binding, structuring and foaming properties.

• Pasteurization substantially improves microbiological control compared with untreated liquid egg.

• Eliminates manual breaking of large quantities of shell eggs.

• Reduces the risk of shell fragments entering food preparations.

• Allows accurate and reproducible dosing.

• Improves industrial recipe standardization.

• Reduces handling of potentially contaminated shells within the food-production area.

• Is particularly convenient for catering, bakery, pastry and industrial food production.

• Is naturally gluten-free when no gluten-containing ingredients are added.

• Is naturally free from dietary fibre and contains very little carbohydrate.

In the United States, USDA FSIS considers pasteurized egg products ready-to-eat from a food-safety processing perspective because they have received a validated lethality treatment and do not require additional preparation solely to achieve food safety.

Disadvantages

• Egg is a major food allergen.

• It is unsuitable for individuals with egg allergy.

• Pasteurization does not mean absolute sterility.

• Post-process contamination can occur if the product is handled or stored improperly.

• Refrigerated liquid products require an effective cold chain.

• Once opened, refrigerated products have a limited usable life and manufacturer instructions must be followed.

• Heat treatment may partially alter some functional properties of egg proteins.

• Whole egg naturally contains cholesterol.

• Pasteurized whole egg may not perform identically to freshly broken shell egg in every highly specialized application.

• Technological properties can vary between commercial products.

• Products containing additional ingredients cannot automatically be regarded as compositionally identical to plain pasteurized whole egg.

Safety, allergens and regulatory considerations

Microbiological safety

Salmonella is the principal pathogen traditionally associated with eggs and egg products. This is one of the major reasons why liquid egg products are subjected to validated lethality treatments.

In the EU, Regulation (EC) No 853/2004 establishes specific hygiene requirements for egg products, while Regulation (EC) No 2073/2005 establishes microbiological criteria applicable to relevant egg-product categories.

In the United States, the Egg Products Inspection Act requires egg products distributed for consumption to undergo pasteurization or another compliant treatment, and USDA FSIS conducts verification and microbiological testing of pasteurized egg products, including testing for Salmonella.

In the UK, the Food Standards Agency identifies pasteurization of liquid egg as an important control measure against foodborne illness and emphasizes appropriate refrigeration and food-hygiene controls.

Pasteurization significantly reduces microbiological risk but does not remove the need for:

• hygienic packaging;

• protection against post-process contamination;

• correct temperature control;

• observance of shelf life;

• hygienic handling after opening.

Egg allergen

Egg and egg products are regulated food allergens in the European Union and United Kingdom. Regulation (EU) No 1169/2011 includes eggs and products thereof among the substances or products causing allergies or intolerances for which specific consumer information is required.

UK Food Standards Agency guidance likewise states that all bird eggs used as ingredients or processing aids must be declared, because the regulated category “eggs” is not restricted only to hen's eggs.

Where an ingredients list is required in the UK, egg must be identified and appropriately emphasized as an allergen.

In the United States, egg is also recognized as a major food allergen under federal food-allergen labelling requirements.

Pasteurization does not eliminate egg allergenicity. A pasteurized whole-egg ingredient must therefore continue to be managed as an egg allergen.

Storage

Storage requirements depend on the exact commercial product and processing system.

For refrigerated liquid pasteurized egg products, the manufacturer's storage instructions and use-after-opening requirements should always be followed. USDA FSIS recommends keeping liquid egg products under refrigeration and specifies limited storage periods for opened products.

Other formats may include:

• frozen pasteurized whole egg;

• dried egg products;

• aseptically packaged or otherwise shelf-stable products.

These formats can have very different storage requirements and shelf lives. Shelf life should therefore not be generalized from one type of pasteurized egg product to another.

For refrigerated products, particularly important controls include:

• maintaining the specified refrigeration temperature;

• keeping the package intact;

• preventing contamination after opening;

• using clean utensils and dispensing equipment;

• respecting the use-by date;

• following the manufacturer's instructions for the period after opening.

Environment

The environmental impacts associated with pasteurized whole eggs arise mainly from poultry farming, feed production, egg collection and transport, processing, pasteurization, refrigeration, packaging and distribution.

Compared with breaking shell eggs individually in large catering or industrial facilities, centralized processing allows shells and membranes to be collected at dedicated egg-processing plants.

Eggshells and other processing fractions may potentially be directed to appropriate recovery or valorization routes depending on local legislation, hygiene requirements and technical feasibility.

Conclusion

Pasteurized whole eggs are an egg product generally manufactured by breaking eggs, retaining the albumen and yolk together, filtering and mixing the liquid egg and applying a validated heat treatment or equivalent lethality process. USDA FSIS describes pasteurization as the most common treatment used to reduce or destroy pathogens in commercial egg products.

The main substances contained are water, proteins and lipids, together with phospholipids, cholesterol, vitamins and minerals. Reference whole-egg composition data indicate approximately 77.1 g of water, 12.4 g of protein and 8.7 g of fat per 100 g.

Technologically, pasteurized whole egg is particularly valuable because it can simultaneously perform emulsifying, binding, structuring, thickening and foaming functions, making it useful in bakery products, pastry, pasta, creams, sauces, desserts and many prepared foods.

Pasteurization provides a major food-safety advantage, particularly in controlling Salmonella, but correct processing, packaging, refrigeration where required and protection against post-process contamination remain essential. EU and US regulatory systems therefore combine pasteurization or equivalent lethality requirements with microbiological and hygiene controls.

Finally, pasteurized whole egg remains a major allergenic ingredient. Egg and egg products must be appropriately identified in foods under EU and UK allergen-information requirements, and comparable allergen-management requirements apply in the United States.

Overall, pasteurized whole eggs are a nutritionally valuable, highly functional and industrially convenient food ingredient. Their correct assessment should consider composition, pasteurization process, microbiological safety, allergen status, storage conditions, technological functionality and compliance with the applicable EU, UK and US food-safety framework.

Studies

Regarding the intake of chicken eggs as its impact on human health, in recent decades, there are conflicting views.

Doubts focus on the cholesterol content and its potential role in cardio-metabolic outcomes.

A whole or boiled chicken egg contains about 15 micrograms of selenium and in addition iron, Vitamin B2, B12, D, E

It also contains lutein, a carotenoid that can be protective against diseases such as age-related macular degeneration (1) and choline, a cellular and nervous restructurer and anti-inflammatory.(2)

Recent studies have also shown that the egg, due to its vitamin D content, helps protect the eyes from cataracts and other degenerative diseases due to ageing.

On the other hand, health recommendations indicate that dietary cholesterol should be limited to less than 200 mg per day; a single large egg yolk contains about 275 mg of cholesterol (3), so taking even a single egg increases LDL cholesterol.

 The consumption of whole egg in the middle-aged and elderly population has long been discussed in the scientific literature.  The impact on the cardiovascular system with possibility of disease has been under observation for several years. However, this study considers that the intake of whole egg does not affect the risk of cardiovascular disease (4).

This study, on the other hand, considers that a high consumption of eggs is significantly associated with a higher risk of contracting incidental cardiovascular diseases (5).

Egg studies