KANSAS CITY — What’s old is new again.

Industry giants are digging through the product graveyards to sate demand for discontinued items. Mars Chocolate North America, Hackettstown, N.J., for example, recently announced the return of M&M’s Crispy beginning early next year. The milk chocolate candies with a crispy center first appeared for a limited time in 1998 and haven’t been on shelves in 10 years. The company said a decade of phone calls, petitions and social media posts culminated in the confectionery comeback.

M&M's Crispy are returning to shelves beginning early next year.

“When M&M’s fans talk, we listen,” said Seth Klugherz, senior director for the M&M's brand. “And consumers have made it clear that M&M’s Crispy are so irresistible, we had to bring them back.”

The announcement follows a similar move from The Coca-Cola Co., Atlanta, which in September resurrected Surge, a citrus soft drink that was offered between 1996 and 2001. Sparking the product’s revival were three Surge enthusiasts who raised nearly $4,000 in 2013 to buy a billboard about a half-mile from the company’s headquarters. The billboard directed people to a Facebook page focused on “The Surge Movement,” which amassed more than 128,000 fans. Representing Coca-Cola’s first re-launch of a discontinued product, Surge was reintroduced for sale exclusively on Amazon.com on Sept. 15 and sold out within hours.

Fans sparked the return of Surge, Coca-Cola's discontinued citrus soda.

And in August Burger King Corp., Miami, rebooted Chicken Fries — thin, breaded strips that debuted in 2005 and flew the coop in 2012.

“On peak days we’ve seen one tweet every 40 seconds about Chicken Fries, many of them directly petitioning, begging, for us to bring them back,” said Eric Hirschhorn, chief marketing officer, North America, Burger King. “When you have guests who are this passionate about a product, you have to give them what they want.”

On Burger King's Facebook page, the chain credited its customers for the revival of Chicken Fries.

Fueling the resurgence of retired products is nostalgia for the bygone bites of better times, especially amidst continued economic challenges. Surge and M&M’s Crispy were comfort-food figments of ‘90s culture, during the childhoods of many millennial consumers.

Meanwhile, in an effort to sustain consumer loyalty, more companies are bowing to passionate pleas on social media and on-line petitions, whether by reformulating products to remove controversial ingredients or by recovering gone-but-not-forgotten menu items and packaged foods.

What’s next? Plenty of on-line pushes abound for other discontinued products, including Crystal Pepsi and French Toast Crunch cereal from General Mills. As another example, a petition on Change.org and a Facebook page with more than 2,500 followers clamor for the return of 3D Doritos, a multidimensional snack chip that was dropped in the mid-2000s.