McDonald’s Corp. has quietly begun selling the McPlant burger in Denmark and Sweden, helping the fast-food giant gauge customer interest in the alternative-meat offering before a wider roll-out.

The trial started in select locations in January, the Chicago-based company said Monday in response to questions from Bloomberg News. McPlant, which McDonald’s co-developed with Beyond Meat Inc., is made from pea-based protein, according to McDonald’s Danish and Swedish websites, revealing previously undisclosed details of the item’s ingredients.

Restaurants are racing to add trendy plant-based items to attract consumers who are concerned about the environment, animal welfare and nutrition. While Burger King in the U.S. market has seen success selling its Impossible Whopper, which is made by Beyond Meat’s main competitor, sales often taper off after the bump in demand from diners trying the item for the first time.

The McPlant burger currently for sale is topped with cheese, lettuce, tomato, pickles, onions, mayonnaise, mustard and ketchup.

The item is cooked on the same grill as beef burgers, the company said, presenting a problem for those who are following a vegan diet. Restaurant Brands International Inc.-owned Burger King faced the same challenge in 2019 with its soy-based burgers cooked on the same broiler as beef and chicken. Other chains have done the same, but often allow customers to request a different grill or the microwave.

McPlant is available to roll out in other markets when they’re ready, McDonald’s said. The Sweden test will last until March 15, while the Denmark trial will run through April 12.

Key Market

Scandinavia is a key market for plant-based alternatives and one that consumer packaged goods companies have prioritized for roll-outs. In 2018, Unilever began selling vegan Magnum ice cream bars in Sweden and Finland.

While McDonald’s will source the McPlant patties for the tests through Beyond Meat, it didn’t specify the suppliers for future roll-outs. Beyond Meat referred questions to McDonald’s. The plant-based meat maker has said that it collaborated with McDonald’s but hasn’t offered many details of the arrangement.

McDonald’s Chief Executive Officer Chris Kempczinski has called plant-based food “an ongoing consumer trend.” The company will be “flexible” with McPlant, which could be sold as a burger, chicken item or breakfast sandwich, he said.