A U.S. company is infusing sunflower seeds with caffeine and other boosters commonly found in energy drinks to offer customers a two-in-one product.

Dakota Valley Products Inc. has been developing the product, called Sumseeds, for about a year.

"A lot of people chew sunflower seeds to stay awake and give them energy, and we just thought we'd combine the two of them," company president Tim Walter said.

The seeds are grown in North Dakota and Kansas, and then shipped to the Carpenter-based company's plant in Willow Lake, South Dakota, where caffeine, taurine, lysine and ginseng are added.

A 3.5-ounce bag was being sold for $1.99 — about twice the price of normal sunflower seeds — at a Sioux Falls drug store chain. They should soon appear on shelves in Minneapolis, Minnesota, and the U.S. Southeast, and a major convenience store chain was testing the snack in 10 of its stores.

Dakota Valley Products was working to get the product into nationwide distribution, and was getting international interest from as far away as New Zealand, Walter said.

Sunflower seeds have long been touted as a healthy snack that is high in protein and fiber and contains vitamins and minerals. But while energy drinks pack in sugar, a bag of Sumseeds contains just 5 grams to give snackers a longer-lasting boost in lieu of a high carbohydrate rush, Walter said.

"Our angle is that you can't consume a sunflower seed as fast as say you could guzzle a 10-ounce or a 12-ounce can of a beverage, and you also don't have that sugar," he said. "So it will be more of a sustained energy boost."

Eighteen- to 30-year-old men make up the largest market for in-shell sunflower seeds, with many chewing and spitting while playing outdoor activities or watching television, he said. Sunflower seeds are also a favorite of truckers, who eat them during long trips.

Dakota Valley Products has two patents pending, one for the way it roasts and cools the seeds, and another for its method of getting the ingredients through the shell and into the kernel, which helps avoid the bitter taste caffeine can add, Walter said.

The National Sunflower Association said Sumseeds would give a boost not just to customers, but also to the industry.

"Any way that there's more products on the market, obviously that's a plus for us and for farmers," the association's international marketing director, John Sandbakken, said.