This is a simplified description of serum albumin proteins – there are more resources available at the bottom of the page for further reading for those who are interested in knowing more.

What are serum albumin proteins?

The most common food allergens are found in plants, but serum albumin proteins are found in mammalian and poultry meats. Different species of animals have slightly different proteins, e.g. bovine serum albumin and ovine serum albumin (where bovine means cows and ovine means sheep). Serum albumin proteins are also very common in humans. They are similarly shaped enough for some people with this allergy to have allergic reactions to all foods containing the same proteins.

Serum albumins are found in the blood , they play a role in transporting various substances through the blood, like hormones and fatty acids and helping to maintain osmotic pressure. Serum albumin proteins are thermolabile, which means they are easily broken down by heating and processing.

An allergy to mammalian meats is more likely to be caused by Alpha Gal Syndrome, than by an allergy to serum albumins. These allergic reactions are delayed in comparison to the usual immediate IgE allergic reactions, so are easy to distinguish.

Which foods contain serum albumin proteins?

The World Health Organization (WHO) recognises 3 foods as containing serum albumin proteins known to cause allergic reactions after consumption of food.

Beef, chicken and pork all contain serum albumin proteins.

Which animal hairs contain serum albumin proteins?

Studies have suggested that sensitisation to these proteins can sometimes come from animal hair (also called dander). Dog hair, guinea pig hair, horse hair and cat hair also contain serum albumin proteins. The most up to date information for foods containing serum albumins are on the Cross Reactivity Tool.

What symptoms do they cause?

Allergy to foods containing serum albumins have a wide range of symptoms and severity including urticaria (hives or welts), angioedema (swelling under the skin), nausea, abdominal pain, vomiting or breathlessness and anaphylactic shock.

What unusual cross reactivity are serum albumins associated with?

Pork-Cat Syndrome is a rare condition, where a person sensitised to the serum albumin in cat hair becomes allergic to eating pork meat.

Bird-Egg Syndrome is when a person is sensitised to chicken serum albumins by either eating eggs or by allergic reactions to feathers and then have allergic reactions to the ingestion of poultry.

What is the importance of knowing whether a reaction is to serum albumin proteins or other allergens?

Multiple allergies are becoming more common and this often leads people to impose a strict restrictive diet on themselves. This can lead to a poor diet lacking in essential nutrients and frustration over a lack of eating options. Knowing which foods are the most likely to be causing your reactions can bring more options back into your diet.

This is why food diaries continue to be an important tool in diagnosis of your allergies – noting the times reactions took place and what medications were taken are a necessary starting point for a proper diagnosis.

There is more information on food diaries HERE.

Allergen Encyclopedia - Cat Dander

Science Direct - Bovine Serum Albumin

Allergen Encyclopedia - Dog Dander

Characterization of relevant bovine dander allergen components, 2024

Albumins represent highly cross-reactive animal allergens, 2023

Sensitization to molecular dog allergens in an adult population: Results from the West Sweden Asthma Study, 2022

Serum Albumin as a Cross-Reactive Component in Furry Animals May Be Related to the Allergic Symptoms of Patients with Rhinitis, 2021

Sensitization to bovine serum albumin as a possible cause of allergic reactions to vaccines, 2017

Update on the bird-egg syndrome and genuine poultry meat allergy, 2016

Pork-cat syndrome? 2015

Serum albumins - unusual allergens, 2013

Bovine Serum Albumin: a double allergy risk, 2013

Panallergens and their impact on the allergic patient, 2010

Chicken serum albumin (Gal d 5*) is a partially heat-labile inhalant and food allergen implicated in the bird-egg syndrome, 2001

Food anaphylaxis to bovine serum albumin, 1998

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