Barley enzymes in gluten-free products
In recent weeks I have been contacted by several members of the gluten-free community and asked to look into the use of barley enzymes in Rice Dream and Soy Dream products labeled gluten free.
I spoke at length with Mohamed Obanni, Ph.D., who is Senior Director of Research and Development and Quality Assurance at the Hain Celestial Group, which manufacturers Rice Dream and Soy Dream products.
According to Dr. Obanni, the only labeled gluten-free products that contain barley-derived enzymes are Rice Dream beverages. These beverages contain a rice base that uses barley-derived enzymes in processing. This ingredient is included in the ingredients list as “brown rice (partially milled).”
Rice Dream frozen desserts also contain this ingredient but barley-derived enzymes are not used in their processing. Soy Dream frozen desserts contain brown rice syrup but do not use barley-derived enzymes in processing. Likewise, Soy Dream beverages contain organic rice syrup but do not use barley-derived enzymes in processing.
Hain Celestial was extremely accommodating and willing to do everything possible to assure gluten-free consumers that Rice Dream beverages labeled gluten free are indeed gluten free. To this end, Hain Celestial agreed to run further tests on the enzyme preparation used in Rice Dream beverages. Dr. Obanni recently sent me the following communication and okayed its inclusion in this article.
“Thank you for your interest in Rice Dream products and for being an advocate of gluten free foods. I also want to thank you for the discussions we have had and advice about testing these products for gluten.
“I am happy to report that we have tested both the enzyme derived from barley in its native as well as denatured states, and the rice base used in Rice Dream products using both R-Biopharm Ridascreen Gliadin competitive assay (i.e., competitive R5 ELISA) and R-Biopharm Ridascreen Gliadin sandwich assay (i.e., sandwich R5 ELISA). The results from Food Allergy Research and Resource Program are Below Limit of Quantification (5 parts per million gluten for R-Biopharm Ridascreen Gliadin sandwich assay and 5 parts per million purified gliadin for R-Biopharm Ridascreen Gliadin competitive assay) for all products tested.
“This confirms our claim that Rice Dream products have tested BLQ for gluten and for gluten peptides. We appreciate your support for educating consumers about our products and clarifying the ambiguities about Rice Dream to the consumers and allergen networks that seek your advice.”
Barley enzymes may be used in the production of brown rice syrup, and similar rice-based ingredients to break down rice starch into sugar. Barley enzymes, depending on how they are produced may or may not be “contaminated” with the barley prolamin hordein (i.e., the prolamin in barley harmful to persons with celiac disease).
According to the cereal chemists I have spoken with, testing for hordein contamination in barley enzyme preparations can be tricky. If the hordein protein remains intact, or mostly intact, the sandwich R5 ELISA can be used to assess hordein contamination. If the hordein protein has been broken down, the competitive R5 ELISA should be used.
To cover all their bases, Hain Celestial tested their barley enzyme preparation using both the R5 sandwich and competitive ELISAs. They also tested their rice base using both assays. All products tested contained below the limit of quantification for gluten. The limit of quantification for the R5 sandwich ELISA is 5 parts per million of gluten; for the R5 competitive ELISA the limit of quantification is approximately 5 parts per million of purified gliadin.
Please note that unlike the sandwich R5 ELISA where assay results are reported in parts per million of gluten, results for the competitive R5 ELISA are reported in micrograms of peptide per gram of food. The limit of quantification for the competitive R5 ELISA is 1,250 micrograms of peptide per gram of food which is approximately equal to 5 parts per million of purified gliadin.
Based on the results of the tests conducted by the Food Allergy Research and Resource Program, the barley enzyme preparation and rice base used by Hain Celestial in their Rice Dream beverages appear to be gluten free (defined as less than 20 parts per million of gluten).
For more information on the steps Hain Celestial takes to ensure products labeled gluten free are indeed gluten free see http://www.glutenfreechoices.com/
Copyright © by Tricia Thompson, MS, RD
Originally published June 2009. Page last updated January 30, 2013.
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