Kraft Heinz revealed on Monday that three months ago it quietly replaced artificial flavors, preservatives, and dye from its signature macaroni and cheese dinners.

Calling it the "world’s largest blind taste test," the company said that it nixed the artificial dyes Yellow 5 and 6 and replaced them with paprika, annatto, and turmeric to achieve its signature neon color. Quietly appearing on store shelves in December, Kraft said it has since sold 50 million boxes—the same amount as usual --without anyone noticing.

“We’d invite Americans to try our new recipe, but they most likely already have,” said Greg Guidotti, vice president of meals at Kraft Heinz in a statement.

The new comes without any new branding, but does include the new ingredients on the label—that is if you were looking for it.

The switch wasn’t a total surprise. Last April, Kraft said it would change the ingredients in its iconic macaroni and cheese to appeal to today's health conscious consumers. The company thought that not telling the public would preempt any consumer perceptions that changing with the recipe would hurt the taste.

Many major food companies, such as General Mills, Mars, Kellogg's, Mondelez, and Nestle, are all in the process of eliminating artificial food coloring from its foods.

But Kraft's stealth move was a gamble. Not all consumers welcomed changes to iconic products, such as Coca-Cola's New Coke and Kool-Aid with natural colorings, when they tweaked recipes.

As of now, there has been little reaction about the switch.

We cooked up an old and new box to see if we could notice a change. The color (yes, it's still the same neon yellow) and texture were pretty close. So we decided to take them to the streets to see if people in New York could tell the difference.

Many people said there was little change in taste, but some noticed a difference.

"You can taste the difference," said one man. "I think they need to work on the formula a little bit."

But overall, when faced with picking a winner between the two, the people we asked went for the original recipe --over the healthier version---even though they knew it had artificial ingredients.

"I ate it a lot when it had it, so it's not going to change my mind," said another taste tester.

But the real question is will it bring back lapsed mac and cheese lovers turned off artificial ingredients--as it was intended.