I saw this today and thought it very interesting - Kraft changed their mac n cheese recipe, last December, to be more healthful but didn't tell anyone until now. The full story http://www.eater.com/2016/3/7/11173858/kraft-mac-and-cheese-different and a few key excerpts:

*Kraft announced that the revamped product would hit store shelves in January — but unbeknownst to customers, it quietly began selling the artificial-ingredient-free mac and cheese in December. (Only consumers who paid careful attention to the tiny print of the ingredients list on the back of the box might have seen the change.) Today, Kraft issued a self-laudatory press release revealing its little experiment — which it has deemed "the world's largest blind taste test" — and proclaiming that "fifty million boxes later ... people didn’t notice a difference."*

*...*

*"We constantly talk to our consumers and get feedback from them, and we knew they wanted to feel better about the ingredients they serve their families," Greg Guidotti, vice president of meals at Kraft Heinz, tells Eater. "We saw an opportunity in the marketplace to improve our ingredient line, but we didn't want make the change before we had the right recipe." While the company only announced its intentions to oust artificial ingredients from mac and cheese in April, Guidotti says they've in fact been working on the new recipe for more than three years.*

*The idea to do a surreptitious switcheroo with the new mac and cheese was born out of the skeptical consumer response to Kraft's initial announcement that it was changing the recipe. "When we announced in April [that we were changing the recipe] there was excitement but also concern, so we saw it as an opportunity," Guidotti says. "We knew the recipe still tasted just as good as you expect from Kraft, but whenever you say you've changed something, consumers will say it probably won’t taste as good. Since we knew it tasted exactly the same, we wanted our fans to experience that for themselves without even being prompted."*

Cheers,

Deb -- Deb Tankersley Product Manager, Discovery Wikimedia Foundation