Soybean hemicellulose
A plant fibre extract from soya beans used to thicken, emulsify and stabilise foods. May contain residual soy protein, a common allergen.
Contains residual soy protein that can trigger allergic reactions in people with soy or legume allergies. Look for 'soybean hemicellulose' on the label.
What is it?
Soybean hemicellulose is a water-soluble dietary fibre extracted from the cell walls of soya beans, specifically from the cotyledon fraction of the bean. It consists mainly of polysaccharides including galactose, arabinose, galacturonic acid and rhamnose chains. Commercial preparations may retain up to around 14% residual soy protein after processing.
What does it do?
Acts as a thickener and stabiliser by forming viscous solutions that slow separation in emulsions. Also functions as an emulsifier by coating fat droplets and as an anticaking agent in powdered products. It is not absorbed intact in the gut but is extensively fermented by intestinal bacteria, behaving similarly to other soluble dietary fibres.
Where you will see it
Used in beverages (soy drinks, plant-based milks), processed soy-containing foods, emulsified sauces, salad dressings, and some meat alternatives. On a UK ingredient label it appears as 'soybean hemicellulose' or 'E426'.
What the science says
Soy allergen carry-over
Soybean hemicellulose can retain residual soy proteins from the extraction process, with commercial samples containing up to roughly 14% protein by weight. Soy is one of the 14 major allergens requiring mandatory declaration under UK food law. The EFSA Panel flagged that the residual protein content in E426 should be reduced as much as possible and that consumers with soy allergy should be informed of its presence.
Commercial E426 preparations may contain up to approximately 14% residual soy protein, which could trigger allergic reactions in soy-sensitive individuals.
EFSA recommended that the amount of residual proteins in E426 be reduced as far as possible, and that labelling inform consumers of potentially allergenic proteins.
Toxicology and genotoxicity
Animal feeding studies at high doses have not found adverse effects attributed to the additive itself. A 90-day dietary study in rats at doses exceeding 2,400mg per kilogram of body weight per day for males showed no treatment-related adverse effects. Genotoxicity tests have returned negative results. EFSA concluded no numerical acceptable daily intake was needed on the basis of available data.
No adverse effects were reported in a 90-day dietary toxicity study in rats at the highest doses tested (around 2,430mg/kg body weight per day for males). Soybean hemicellulose was not considered of genotoxic concern.
No numerical ADI was set. EFSA considered it very unlikely that there is a safety concern from the current use levels as a food additive.
Gut fermentation and fibre behaviour
E426 is not absorbed as a whole molecule. It is broken down by bacteria in the large intestine in a similar way to other soluble dietary fibres. This means it contributes to colonic fermentation but does not enter the bloodstream intact. Actual dietary exposure from its use as an additive is likely to be negligible given limited use across food categories.
Soybean hemicellulose is extensively fermented by intestinal microflora in both animals and humans and is not absorbed intact.
Where it stands with the regulators
Who should be careful
People with a soy allergy or soy intolerance. Soy is a declared allergen under UK food law, but soybean hemicellulose is derived from the fibre fraction rather than soy protein, so it may not always be labelled as containing soy. Look for 'soybean hemicellulose' or 'E426' on the label and treat it as a potential soy allergen source.
The honest read
The main documented issue with E426 is allergen carry-over, not toxicity. The additive itself is a plant fibre that behaves like other soluble fibres in the gut and has not raised toxicological red flags in formal studies. The open question is how much residual soy protein survives into finished food products when E426 is used as an ingredient, which depends on the supplier's manufacturing process. People without soy allergy are unlikely to encounter any particular issue from this additive at the amounts typically used in food. The allergen concern, however, is real and was formally flagged by EFSA.
Related additives
Common questions
Is E426 banned in the UK?
No. Soybean hemicellulose (E426) is authorised in Great Britain under retained EU law and on the UK FSA approved-additives list.
Can E426 cause an allergic reaction?
Possibly, if you have a soy allergy. E426 is extracted from soya beans and commercial preparations can retain residual soy protein. EFSA flagged this in 2017 and recommended manufacturers reduce protein content and that labelling inform consumers. If you have a soy allergy, treat any food listing E426 or 'soybean hemicellulose' as a potential trigger.
What foods contain E426?
Soybean hemicellulose is used in soy-based beverages, plant-based milk alternatives, emulsified sauces, salad dressings, and some processed or powdered foods. It appears as 'soybean hemicellulose' or 'E426' on the ingredients list.
Is E426 vegan?
Yes. Soybean hemicellulose is derived entirely from soya beans, a plant source, and contains no animal-derived ingredients.
Sources
- EFSA ANS Panel: Re-evaluation of soybean hemicellulose (E 426) as a food additive, EFSA Journal 2017
- PubMed: Re-evaluation of soybean hemicellulose (E 426) as a food additive (PMC7010024)
- UK FSA Regulated Products Register: E-426 Soybean Hemicellulose
- UK FSA: Approved additives and E numbers
- Commission Regulation (EU) 2020/279 amending Annex II to Regulation 1333/2008 as regards soybean hemicellulose (E 426)
- EUR-Lex: Commission Regulation (EU) 2020/279 of 27 February 2020
- EU Regulation 1333/2008 on food additives (Annex II), assimilated UK version
- EU Regulation 231/2012 laying down specifications for food additives
See this on every food you scan
NutraSafe reads the label and puts every additive into plain English, with the source, right in the app.
Get NutraSafe on the App Store