Cellulase
An enzyme derived from fungi that breaks down plant fibre, used mainly as a processing aid in juice, wine, and bread making.
What is it?
Cellulase is a group of enzymes (EC 3.2.1.4 and related classes) that catalyse the breakdown of cellulose, the structural polysaccharide in plant cell walls. Commercial food-grade preparations are produced by controlled fermentation of fungi such as Trichoderma reesei (longibrachiatum), Aspergillus niger, or Penicillium species. The enzyme protein itself is present in trace amounts or completely inactivated in the final food product, as it is used in processing and typically denatured during heating.
What does it do?
Cellulase cleaves the beta-1,4-glycosidic bonds in cellulose chains, releasing shorter glucose oligomers and eventually glucose. In food processing, this softens plant cell walls, which improves juice yield when pressing fruits and vegetables, clarifies juice and wine by breaking down suspended plant cell debris, improves the extractability of colour and flavour compounds, and aids in bread dough conditioning by modifying the fibre fraction in wholegrain flours.
Where you will see it
Fruit and vegetable juice production (apple, pear, citrus, grape), wine making, beer brewing, wholegrain bread and bakery products, and plant-based food processing. Because cellulase is primarily a processing aid rather than a functional additive in the finished product, it often does not appear on the ingredient label. When it does appear, it is typically listed as 'cellulase' or simply 'enzyme' or 'enzymes'.
What the science says
Safety at food-processing levels
Cellulase proteins are digested normally in the gut like other dietary proteins. At the levels used in food processing, and given that active enzyme is typically not present in the finished product after heat treatment, regulatory reviewers have not identified a consumer safety concern. EFSA's Panel on Food Enzymes has evaluated numerous microbial cellulase preparations and found no toxicological signals warranting a numerical ADI.
EFSA's Panel on Food Enzymes (FEZ) has evaluated individual cellulase preparations sourced from Trichoderma reesei and Aspergillus niger and concluded no safety concern at the proposed use levels, with no numerical ADI required.
Occupational allergy to enzyme dusts
There is a well-documented occupational health concern with inhaling enzyme powders in industrial settings, including cellulase. Bakers and food factory workers exposed to airborne enzyme dust can develop occupational asthma and rhinitis. This is an inhalation hazard in manufacturing, not a risk from eating food that was processed using the enzyme.
Occupational exposure to fungal enzyme dusts, including cellulases from Trichoderma and Aspergillus species, is a recognised cause of occupational asthma among enzyme manufacturing and food industry workers.
Regulatory status of food enzymes in the UK and EU
In the EU and UK, food enzymes are regulated under a separate framework from food additives. EU Regulation 1332/2009 established a procedure for authorising food enzymes. A Union list of permitted food enzymes was under development at EFSA for many years. Until the Union list is finalised and applicable, national provisions continue to apply. The E1108 code is used in some national and database contexts but cellulase does not appear in the Annex II positive list of food additives under EU Regulation 1333/2008.
EU Regulation (EC) No 1332/2009 on food enzymes establishes that food enzymes require authorisation and inclusion in a Union list. EFSA is completing safety evaluations of enzyme preparations submitted under this framework.
Where it stands with the regulators
Who should be careful
People with known allergies to mould or fungi (Trichoderma, Aspergillus, Penicillium species) could theoretically react to residual enzyme protein in unheated products, though this is not established as a recognised food allergy trigger at consumer levels. Workers handling raw enzyme powders industrially should follow occupational health controls. No specific population is advised to avoid foods processed with cellulase on the basis of the science currently available. Look for 'enzyme' or 'cellulase' in the ingredients list, though it often appears without labelling as a processing aid.
The honest read
Cellulase is one of the most ordinary tools in food processing, used in roughly the same way as yeast or rennet: a biological catalyst that does its job during production and is typically denatured before the product reaches your plate. The science reviewed by regulatory bodies has not turned up toxicological signals at food-use levels. The one genuine occupational concern, inhalation of enzyme dust, is a factory floor issue, not a supermarket one. The Union list process under EU Regulation 1332/2009 is taking many years to complete across all food enzymes, which means the regulatory picture is administrative rather than a reflection of a safety problem.
Related additives
Common questions
Is E1108 banned in the UK?
No. Cellulase is not banned. It is used as a processing aid and food enzyme in the UK and EU under food enzyme legislation. The Union list of permitted food enzymes under EU Regulation 1332/2009, which is being compiled by EFSA, is still being finalised, but this is an administrative process rather than a restriction on use. Individual cellulase preparations have received favourable EFSA safety opinions.
Does cellulase stay in the food I eat?
Usually not at active levels. Cellulase is used during processing and is typically denatured by the heat used in pasteurisation or baking. In cold-pressed juices or unheated products, trace residual enzyme protein may be present, but at levels well below those evaluated in safety studies.
What foods contain E1108?
Cellulase is used in fruit and vegetable juice production, wine making, beer and cider production, and wholegrain bread and bakery products. It may appear on the label as 'cellulase' or 'enzyme', or it may not appear at all if it is used solely as a processing aid and leaves no functional trace in the finished product.
Is E1108 vegan?
Yes. Commercial food-grade cellulase is produced by fermenting fungi such as Trichoderma or Aspergillus species and contains no animal-derived ingredients. The enzyme itself is a protein of microbial origin.
Sources
- Regulation (EC) No 1332/2009 of the European Parliament and of the Council on food enzymes
- EFSA Panel on Food Enzymes (FEZ) opinions - European Food Safety Authority
- UK FSA Approved Additives and E Numbers
- UK FSA regulated products register - Cellulase (feed, Trichoderma longibrachiatum)
- European Commission Food Improvement Agents - Enzymes
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