WASHINGTON — Record-keeping will be key for manufacturers wanting to use a gluten-free label for foods that are fermented or hydrolyzed or that contain fermented or hydrolyzed ingredients. The US Food and Drug Administration on Aug. 12 issued a final rule, which may be found here, that establishes requirements for such gluten-free labeling.

The FDA listed examples of fermented or hydrolyzed foods as cheese, yogurt, sauerkraut, pickles and green olives. The ruling also covers distilled foods such as distilled vinegar as well as hydrolyzed plant proteins used to improve flavor or texture in processed foods like soups, sauces and seasonings.

The FDA in the ruling said it knows of no scientifically valid analytical method that is effective in detecting and quantifying with precision the gluten protein content in fermented or hydrolyzed foods in terms of equivalent amounts of intact gluten proteins. The FDA thus will evaluate compliance based on records made and kept by the manufacturer. Examples of records showing a food is gluten-free before being fermented or hydrolyzed include test results, certificates of analysis (CoAs) or verification documentation for each ingredient in the food.

Manufacturers also should document how it has evaluated the potential for gluten cross-contact. If such potential is identified, the manufacturer needs to show how it has implemented measures to prevent the introduction of gluten during the food manufacturing process.

People with celiac disease need to avoid gluten, which is a mixture of proteins found in some grains, including wheat, rye and barley.

“These new compliance requirements for labeling a product ‘gluten-free’ will protect individuals with celiac disease, an incurable, hereditary disorder that millions of Americans, including myself, live with,” said Alex M. Azar, secretary of the US Department of Health and Human Services. “The FDA’s final rule helps to ensure common products labeled ‘gluten-free’ really are gluten-free, equipping consumers to make the best choices for their health and their families.”

The FDA in the Aug. 5, 2013, issue of the Federal Register defined the term “gluten-free” as food with less than 20 parts per million of gluten.