Starbucks Corp., the world’s largest coffee-shop operator, is introducing food without preservatives and additives to entice more customers to include a muffin or sandwich with their drink order.

Fresh Oregon blueberries are replacing artificial ingredients in muffins and baked goods, while the Marshmallow Dream bar will come without high-fructose corn syrup, said Sandy Stark, vice president of the food division.

Two salads, an egg-white breakfast sandwich and a strawberry-banana Vivanno smoothie round out the new food options in U.S. stores.

“We really wanted to up the quality of our food,” Stark said last week. “We wanted something that we could be as proud of as we are with our coffee, and we knew we had a long ways to go.”

The new foods are appearing after more than a year of testing and reworking recipes with a focus on healthful, natural ingredients, Stark said. Last year, the company redesigned its breakfast sandwiches following complaints that the smell overpowered the coffee aroma in stores.

Food accounted for 15 percent of the Seattle-based company’s sales of $10.4 billion in the year ended in September, according to a regulatory filing. Starbucks coffee ranked first among fast-food chains in a Zagat survey this month.

“People aren’t going there for the food, aside from the indulgent” treats, said Tom Forte, an analyst with Telsey Advisory Group in New York. While Starbucks isn’t likely to become a food destination, “anything they can do to drive incremental traffic would be a positive,” he said.

Bloomberg News