The change affects the company's Kraft Singles in the full-fat American and White American varieties, which Kraft says account for the majority of the brand's sales. Sorbic acid is being replaced by natamycin, which Kraft says is a "natural mold inhibitor." CN DOMAIN 

Last October, Kraft announced it would remove artificial coloring from several Mac & Cheese varieties. Its changes come as a growing number of Americans try to stick to diets they feel are natural. That has prompted a number of food makers to change their recipes.   CN DOMAIN 

Last week, Subway said it was removing a chemical from its bread after a popular food blogger named Vani Hari started a petition noting the ingredient is also used in yoga mats.

The ingredient, azodicarbonamide, is used by a wide variety of chains including McDonald's and Starbucks, but Hari said she targeted Subway because of its healthy food image. 

Even though such ingredients are permitted by the Food and Drug Administration, being able to tout a product as being free of them can be a selling point. Kraft, for example, plans to begin airing TV ads near the end of February touting that its Kraft Singles cheese "begins with milk" and are now "made with no artificial preservatives." 

The ads show cartoon cows grazing in a pasture, with a milk truck driving past.  CN DOMAIN 

The new Kraft packages, which began appearing on supermarket shelves in recent weeks, also come stamped with a red circle noting they have no artificial preservatives or flavors. Kraft says its cheese slices haven't used artificial flavors for many years, but that it just recently decided to advertise that aspect of the product. 

"Consumers are looking for those less artificial cues and messages," said Gavin Schmidt, manager of cheese research and development at Kraft. "Those messages are more meaningful to consumers than they have been in the past." 

Schmidt says the change took about five years to perfect because Kraft wanted to ensure the product's taste and shelf life remained the same. He declined to provide details, but said it wasn't as simple as swapping out an artificial preservative and replacing it with a natural one. 

"There's a little more to it than that," he said.  CN DOMAIN 

Schmidt said Kraft is testing the removal of artificial preservatives from its other Kraft Singles varieties, but wanted to start with the most popular lines first. The changes do not affect Kraft Singles that are 2 percent fat, fat-free or other full-fat varieties. 

Kraft Foods Group, based in Northfield, Ill., also makes brands including Oscar Mayer, Jell-O, Planters and Maxwell House. CN DOMAIN