Kraft Foods Inc. manufactures various brands including Kraft, Nabisco, and Maxwell House food products. - 

Maxwell House coffee gets a makeover today. The Kraft brand is unveiling a new logo, new packaging, and, bringing back its “good to the last drop” tagline – to remind consumers how good it is, it says. But is it a good idea to tinker with a classic brand’s identity?

An idea that might have seemed great a few decades ago-- we're talking about Quaker Oats’ old version of Aunt Jemima--might not seem so hot just a little bit later. But even when brands need to make big changes, they need to step carefully, says Dave Reibstein, a professor of marketing at the Wharton School of Business.

“In general, what it is you want to do is to be very, very, very consistent with your brand,” Reibstein says, especially to avoid the worst case scenario. “I walk down the aisle and I don’t even see it."

Tom Meyvis, a professor of marketing at the Stern School of Business at New York University, cites Brawny paper towel's sucessful handling of an image problem the brand had with its illustrated spokeman.

“The Wall Street Journal described him as a 70s porn star," Meyvis says.

But, Meyvis notes, that brand handled its image right–by taking baby steps. It slowly shrank the problem mustache, and character, until they were replaced by one a little more up to date. But Matt Egan, senior director of strategy for Siegel+Gale, a brand consultancy based in New York, says even though Kraft says its coffee has a brand new campaign, relying on its old slogan, "Good to the last drop," may not do the trick.

"When a food company resorts to talking about goodness," he says, "that’s always a sign they don’t have much of a real story to tell."