COPENHAGEN — For the last seven years, Marianne Orum has owned a narrow store in a charming street in the heart of this Danish capital.

A sign advertises “British and South African Food and Drink.”

The shelves are lined with products familiar to most Americans, like Betty Crocker Pancake Mix, but also more exotic items, like Heinz’s Taste of Home Delightful Spotted Dick Pudding in cans, and bottles of Harviestoun Old Engine Oil porter.

But in January Ms. Orum got a phone call from government food inspectors. Tipped off by a competitor, they told her she was selling products that were fortified with vitamins or minerals, and such products require government approval, which she did not have, so she would have to take them off the shelves.

The culprits were Ovaltine; a shredded wheat cereal called Shreddies; a malt drink called Horlicks; and Marmite, the curiously popular yeast byproduct that functions in England as a sandwich spread, snack or base for a soup (just add boiling water), and is sometimes known as tar-in-the-jar.