Successful companies have something called Brand DNA, the unique thing they offer.

“If you think of Nike, you think family entertainment,” said marketing expert Carlos Torelli at the University of Minnesota. “If we think Nike, we think superior athletic performance.”

And when people think about Chipotle? “We think natural and fresh,” he said.

But in the wake of foodborne illness outbreaks tied to Chipotle’s restaurants, the way the fast casual restaurant delivers on its “fresh” brand is changing.

Some produce is now prepped, washed and tested at central kitchens instead of in restaurants. Beef barbacoa and carnitas were already cooked off-site, but now the steak will be, too.

Torelli says it’s not clear if those changes will compromise the fresh taste and fresh brand.

“What’s the turnaround time?” he asked. “How many central locations are serving different restaurants? How quickly do they bring it? How much does the flavor suffer in that process?”

At a tech and retail conference Wednesday, Steve Ells, founder and co-CEO of Chipotle, said the safety measures are actually making the food taste better. He noted that the steak will be pre-cooked using a slow-cooking method called sous-vide.

“It is a technique that was invented by chefs in the 1970s and still widely used by top chefs and top restaurants all over, where you can precisely cook proteins and hold them at exacting temperatures for certain time periods to have a certain texture or a certain succulence or juiciness, ” he said. “The result is the steak is more tender.”

But to get people in the door eating, say steak burritos, Chipotle admits it’s currently giving away a lot of free food. That’s concerning to Stephen Anderson, a restaurant analyst at Maxim Group.

“I think that, more than anything else, might send a damaging brand message that their burritos may not be worth much,” he said.

Anderson lowered his rating of Chipotle shares this week to “sell” from “hold” on concern that the big, expensive freebies and discounts will last a long time.