Previous research has reported that food scientists who inhale enzymes in the workplace may become sensitive to the enzyme and develop an allergy. But encapsulation of the enzymes, in parallel with improvements in dust and handling during processing has minimised this risk. No reports on sensitization to enzyme ingestion have been reported.
However, with an estimated four per cent of adults and eight per cent of children in the 380m EU population suffering from food allergies (European Federation of Allergy and Airways Diseases Patients' Associations) the development of GM enzymes may cause an allergic reaction by introducing foreign food proteins into foods that were previously tolerated by allergic patients.
The new research, by researchers from Odense University Hospital, the National University Hospital, and Novozymes, investigated the safety of 19 authority-approved and commercially available enzymes used in the food industry, including 13 GM enzymes.
The authors, led by Carsten Bindslev-Jansen from Odense University Hospitals Department of Dermatology and Allergy Center, recruited 400 adults with diagnosed allergies ranging from cows milk and tree nuts, to cats and penicillin.
The subjects were tested for an allergic response by using skin prick testing with the 19 enzymes (13 GM, 6 non-GM), and blood samples taken to measure histamine levels. Patients with positive results were re-tested with purified enzymes and challenged orally in a double-blind, placebo-controlled manner.
The enzymes tested included alpha-amylase, pectin lyase, lipase, beta-glucanase, and protease, and the same test batches are also used by Novozymes when testing workers for potential occupational enzyme allergies.
While some positive results from the skin prick testing were obtained, none of the patients tested positive after oral tests with higher doses of enzymes.
A wide variety of enzyme classes and origins was included in the study. Because there were no allergenic findings of clinical relevance it is concluded that ingestion of food enzymes in general is not considered to be a concern with regard to food allergy, wrote Bindslev-Jansen in the Elsevier journal Food and Chemical Toxicology (Vol. 44, pp. 1909-1915).
In Europe, new legislation has been proposed by the EC to harmonise rules on food enzymes. Currently, food enzymes used during the processing of foods, but not active in the final product (processing aids) are not covered by EU legislation, and in the UK are regulated under General Food Law.
A draft regulation proposed by the European Commission in July would allow for the establishment of a positive list of all food enzymes used in food for a technological purpose, based on favourable scientific opinions from EFSA. The proposal also includes requirements for the labelling of food enzymes other than those used as processing aids.