Xylanase

What it is

Widely used in the baking industry to improve dough workability and increase bread volume.

How it is used in food

Xylanase breaks down arabinoxylan, the hemicellulose in cereal bran that binds large amounts of water. Redistributing that water is what makes it the most widely used baking enzyme after amylase: dough becomes more extensible and machine-friendly, loaves gain volume and a finer crumb, and staling slows. It also raises extract yield in brewing and improves filtration, cuts viscosity in fruit juice and starch processing, and is added to animal feed to release nutrients from cereal fibre.

• Bread and bakery products
• Brewed beers
• Animal feeds
• Fruit juices

Health and safety

Generally recognized as safe (GRAS). Xylanase breaks down complex carbohydrates and poses no known health risks in food applications.

EFSA's Panel on Food Contact Materials, Enzymes and Processing Aids has assessed numerous xylanase preparations from Aspergillus, Trichoderma and Bacillus production strains and concluded there is no safety concern at intended use levels; the enzyme is denatured by baking and digested as protein, and several preparations are GRAS-notified in the US. Reviews consistently flag respiratory allergy as the real risk, and it is occupational rather than dietary — xylanase is a documented cause of baker's asthma and sensitisation in workers inhaling enzyme dust, which is why commercial preparations are sold as granulated or liquid low-dust formulations.

Regulatory status

Worth knowing

Xylanase performance depends heavily on which arabinoxylan it prefers — enzymes that attack the water-unextractable fraction improve bread, while those that further degrade already-soluble arabinoxylan can make dough sticky and collapse the loaf. Formulators therefore select strains for substrate specificity rather than raw activity. The same enzyme family is used to bleach paper pulp with less chlorine, which was one of its earliest industrial applications.

Conclusion

There is no reason to avoid this standard enzyme when it appears in your food. Widely used in the baking industry to improve dough workability and bread volume, it safely breaks down complex carbohydrates. The enzyme is denatured by baking and digested as a normal protein.