Safety Evaluation of the Food Enzyme D-Allulose 3-Epimerase from Genetically Modified Escherichia coli

The EFSA opinion formulators need to know

If you source D-allulose for a formulation, the enzyme behind it matters. In 2021, EFSA published a safety assessment of a food enzyme that converts fructose into D-allulose. The enzyme comes from a genetically modified strain of Escherichia coli. The conclusion is straightforward: no safety concern when you use the enzyme in immobilized form.

Background

D-allulose (also called D-psicose) is a specialty carbohydrate. Producers make it by processing fructose. The key step is enzymatic isomerization. That is where D-allulose 3-epimerase does its job.

The enzyme in this EFSA opinion is an immobilized preparation derived from genetically modified E. coli. The production organism expresses the epimerase. EFSA evaluates food enzymes under EU rules. This opinion, DOI 10.2903/j.efsa.2021.6565, covers the safety of that preparation.

What the study did

The applicant asked EFSA to evaluate the enzyme as an immobilized preparation. Fixed to a support, the enzyme contacts fructose syrup, converts part of it into D-allulose, and then remains with the system.

Here is the critical detail. The downstream purification steps remove residual total organic solids. EFSA therefore did not calculate dietary exposure. The panel also saw no need for toxicology studies. That stands out. Most enzyme assessments at least attempt an exposure estimate. This one did not.

Key findings

EFSA's panel examined the production strain, the manufacturing process, and the intended use. Their findings sit neatly in a table:

Assessment step	What EFSA found
Production host	Genetically modified E. coli, accepted for enzyme production under the specific conditions
Form of enzyme	Immobilized preparation for fructose processing
Dietary exposure	Not calculated because purification removes residual total organic solids
Toxicology studies	Not considered necessary
Conclusion	No safety concerns when used as an immobilized preparation

Notice the pattern. The word "immobilized" appears throughout. The safety conclusion is tied to that form. Free liquid enzyme or crude enzyme would not be covered by this opinion.

What it means for manufacturers

Buyers should treat this opinion as a procurement marker. Ask your enzyme supplier whether their product matches the immobilized form assessed by EFSA. If a supplier changes to a soluble enzyme or alters downstream purification, the safety picture changes too.

For formulators, the operational step is clear. If you specify D-allulose made with this enzyme, confirm that your supplier uses the immobilized preparation. Ask for evidence that the purification train matches the process EFSA reviewed. That protects your product if regulators ask questions later.

The missing dietary exposure value is not a red flag. It is a deliberate outcome. Because the purification steps remove enzyme-derived residues, exposure falls below the level where calculation makes sense. For an ingredient buyer, that is useful context when your own compliance team reviews the supply chain.

FAQ

Is D-allulose 3-epimerase safe? Yes. EFSA concluded that the food enzyme does not raise safety concerns when used in immobilized form for fructose processing.

Why didn't EFSA calculate dietary exposure? Downstream purification removes residual total organic solids. The final D-allulose product carries no measurable enzyme residue, so exposure was not calculated.

Does the GM production host matter? The enzyme comes from a genetically modified E. coli strain. EFSA reviewed that host and the genetic modification as part of the full assessment. The conclusion covers the final immobilized preparation.

Closing

Use this opinion when you talk to suppliers. Ask for the EFSA reference. Confirm the enzyme form. Then match your process to the assessed conditions. That is how a single safety assessment becomes part of your sourcing checklist.