Enzymes intended for food processing or as food additives are regulated by FDA and must meet GRAS (Generally Recognized as Safe) status or have an approved food additive petition. Industrial enzymes used in textiles, paper, or biofuels are regulated under TSCA as chemical substances. Importers should clearly document the intended end use, as the same enzyme protein may face different regulatory pathways depending on application.

Prepared enzyme mixtures are classified based on the essential character of the preparation, typically the primary active enzyme component. When a mixture contains several enzymes of roughly equal commercial importance, classification may require a CBP binding ruling. Importers should provide technical specifications identifying each enzyme component, its activity units, and the intended application to support accurate classification.