Burger King spent a decade engineering its new "guilt-free" fries.

The crinkle-cut "Satisfries" debuted this week and have 40% less fat than the "leading french fries," reports Daniel Gross at The Daily Beast. The fries are made with a special batter that supposedly absorbs less oil than regular fries.

Finding the right recipe took considerable effort, Gross writes.

"The innovation here, which took 10 years of research and development on two continents, is in the batter," Gross said. "There’s something about the makeup of the batter that ensures the potatoes absorb less oil even while producing the desired crispy/fluffy contrast between outside and inside."

Burger King hopes the fries will lure customers who are seeking healthier options.

McDonald's has responded to the health food trend by releasing premium McWraps, Egg White Delight breakfast sandwiches, and a Blueberry Pomegranate smoothie this year.