and Honey Mustard. Like Kraft, ConAgra maintains a policy of divulging gluten ingredients on its product labels. Gulden's mustards don't contain gluten ingredients but aren't labeled gluten-free ...

The question is whether it will spread to the U.S. Kraft Heinz, which owns Grey Poupon, and McCormick, which makes French's mustard, don't foresee empty shelves in U.S. grocery stores.