A study demonstrating a new way to test for the presence of gluten in enzyme supplements has been published in the Journal of Nutrition & Food Sciences.
The study was motivated by the growing demand for gluten free products and the need for accurate testing methodologies for products claiming to meet the gluten free standard of less than 20 ppm, according to coauthor Dr John Deaton, VP of science and technology for Deerland Enzymes & Probiotics.
The most accurate method used to detect gluten is Competitive ELISA (enzyme-linked immunosorbent assay), which is adept at analysing fermented and hydrolysed products such as soy sauce. Yet, said Dr Deaton, there has been no validation for competitive ELISA tests on products that contain active proteases, notably enzyme supplements.
"In fact, the competitive ELISA test is likely to result in a false positive for gluten in fermented or hydrolyzed substances because active proteases degrade the protein of interest in the competitive ELISA, interfering with the assay."
A challenge frequently encountered with using competitive ELISA to analyse enzymes that do not contain gluten is that often the result for gluten contamination are very high and the cause is unknown; the prevailing thought is that the enzymes destroy antibodies of the test format, leading to false positive results.
Dr Deaton and his team investigated the outcome of the competitive ELISA in supplemental enzyme by adapting an extraction method.
In the study, the team spiked enzyme solutions with gluten then tested for gluten content using competitive ELISA kits and another type, sandwich ELISA kits; additional enzyme samples were deactivated by increasing the extraction temperature to 100 degrees centigrade, and these were also tested using both ELISAs.
The results, noted Dr Deaton, showed that "to test enzyme products for gluten using the competitive ELISA, the protease must be deactivated for more accurate results".
Dr Deaton added: "Gluten in foods, including supplements, has risen to the forefront of consumer concerns. Utilizing accurate testing is more critical than ever to ensure that reaching standards for claims of gluten-free is easier and more reliable."
Scott Ravech, CEO of Deerland added: "As a company, our commitment to science goes far beyond the products we develop; we feel it is our responsibility to utilize our expertise to make contributions that benefit the industry as a whole."
