Researchers suggest that heating may denature the protein.
Some disposable eco-friendly dishes are made from wheat straw or bran – raw materials that potentially contain gluten. Researchers studied several commercially available biodegradable products and published preliminary results in the ACS Journal of Agricultural and Food Chemistry. During the study, it was found that one of the plates contained gluten and could transfer the allergen to food and beverages in amounts exceeding the permissible limits for a gluten-free diet. Scientists emphasize that such dishes are not subject to mandatory allergen labeling, which may pose a health risk for people with celiac disease or gluten sensitivity.
Biodegradable dishes are usually made from natural components, including bamboo fibers, sugars from algae, as well as proteins from milk, eggs, soy, or wheat. However, the issue of allergen transfer from disposable plates, cups, and straws to food and beverages has not been sufficiently studied. Even a small amount of gluten can trigger an immune response, digestive issues, and other adverse effects in sensitive individuals. Therefore, the research team decided to assess the presence of gluten in biodegradable products and check whether this protein transfers to solid and liquid food under conditions close to real-life scenarios. In the first phase, scientists tested eight items of tableware, including plates, cups, and straws, which were marketed as biodegradable and made from by-products of wheat processing or other materials that potentially contain gluten. Gluten was found only in one product – a wheat-based plate.
Next, in 30-minute experiments, gluten-free products were placed on various items of tableware at room temperature, after which the level of gluten was measured and compared with the regulatory thresholds established in the EU and the USA. It turned out that gluten transfer occurred exclusively from the wheat-containing plate and affected omelets, rice, milk, and plant-based cream. In solid food, the level of contamination was significantly lower than in liquids: in rice, the gluten content remained within permissible values for a gluten-free diet, in the omelet it corresponded to the category of low-gluten products, while in milk and especially in plant-based cream, the concentration significantly exceeded safe thresholds.
In some cases, heating food in a microwave on such a plate led to lower contamination compared to samples at room temperature. Researchers suggest that heating may denature the protein, thereby reducing its ability to transfer to food. The authors of the study strongly urge the introduction of mandatory labeling for materials in contact with food regarding the presence of gluten. They also note the need for further research to determine whether biodegradable dishes can contribute to cross-contamination with other allergens, such as milk, soy, or nut proteins.
