Are Flavored Buns The Next Fast Food Frontier? Burger buns with a taste all their own seem to be a trend, but can it last?

While it may be true that it's what's on the inside that counts, burger joints around the country are finding that the outside shouldn't be ignored, either. Burger King's A1 burger made its black-bunned debut in time for Halloween and the pretzel bun was an unprecedented success for Wendy's. The latest is a limited-time-offer from Wayback Burgers until the end of the year: a sriracha-infused bun for the Crispy Chicken Sriracha Sandwich.

While some oddly-colored buns may miss the mark, the focus on flavored bread for burgers is an interesting trend -- if we can call it that.

"It's not a trend, but rather a fad," says Darren Tristano, the executive vice president of food-industry focused research and consulting firm Technomics. The difference between the two terms, he says, is the length of time implied."Trends are longer term and sustainable," he says. "In the short term, we'll see more of this, but in the long term, it's more likely to fizzle out. We won't be talking about this in 2017."

The problem, he says, is that restaurants don't often have the ability to bake the bread on-site before infusing the flavor, and ordering an amount from suppliers will be difficult because there's no way to know what the demand for the product will be. Instead, Tristano thinks the real trend is integration of retail products and restaurant products. Consider the Doritos shell for Taco Bell or Subway's recent push to include Fritos chips on a sandwich.

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Cheryl Fogarty has a different idea. "I think the overarching theme is more about flavor," she says. As a former director of consumer insights at Jack in the Box and a current analyst at Sandelman, a market research firm for the foodservice industry, Fogarty knows about food trends. "Bread has always been a driver and a lot of folks look to interesting bread," she says.

To support her claims, she mentioned the results from a study from October to December of 2014 that showed 44 percent of early adopters said an interesting bread or bun would get them to try a new item. "The trick is to find something broadly appealing that's also a twist on the familiar," she says.

Chains have already put twists on menu items by experimenting with toppings and sauces and even different types of meat. There's the cheese-stuffed patty, a patty that holds Reese's peanut butter cups inside, and a 50/50 burger patty that is made of both ground beef and bacon.

Elizabeth Friend, a strategy analyst at the market research firm Euromonitor, sees the experimentation with buns as the next logical step. "We got to a certain point where it was a natural next step to start playing with the bun. It feels more tangibly different because we can see the difference right away, and it's textually different," she says. "After different types of bread, it's color, flavor infusion. Considering how tough everything is out there for fast food in the U.S., no innovation is considered too far right now."

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What's coming next depends on whom you ask. While Tristano sees the industry moving toward an emphasis on fresh ingredients and preparation -- a move that benefits fast-casual restaurants more than major burger chains -- the specific trend matters less than the effect it has. "You gain attention through buzz marketing," he says. "It's not the success of the sandwich but the buzz of the brand [that matters]. If it's talked about more it gets more business from customers."

For Friend, the future might mean focusing on plainer offerings. "I think we'll see more streamlined menus and simplicity in menu items," she says. "A return back to basics might be the next evolution." She points out that limited-time offers are expensive to develop and hard to implement for restaurants with so many locations. Moreover, she says, large menus with a multitude of options cut into profit margins. Fogarty agrees, saying, "Smaller chains have flexibility to play with the menu and come up with unique, innovative types of products."

Really, though, what it comes down to is differentiation. "That tends to be where success lies today: differentiating, offering the best of what you do," Tristano said. "[Fast-food chains are] fast, affordable, and consistent, so there's a ceiling on how much innovation a fast-food restaurant does."

It doesn't seem like we've hit that limit yet. "We'll cycle through this, but we're not at the end of this trend yet, that's for sure," Friend says.

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