Eyeing add-on sales, particularly among refreshment-seeking Millennials, a growing number of restaurant operators are grooming their iced coffee lineups.

Credit major iced coffee purveyors such as Starbucks Coffee, Dunkin’ Donuts and McDonald’s with seeding a large and growing market. All told, for the year ended February 2014, there were 895 million servings of iced coffee ordered at U.S. restaurants and foodservice outlets, according to the NPD Group’s CREST market research. That marks an increase in servings of 5  percent compared with the same period a year prior.

If iced coffee was a “nice to have” menu item in bakery-café restaurants a few years ago, it is a must-have today, says a segment insider.

“Now, if you want to be a café at all, you have to have some kind of iced coffee,” says Judy Kadylak, vice president of marketing for Bruegger’s Bagels, a 302-unit chain of bakery-cafes based in Burlington, Vt. “I think iced coffee is definitely a bigger part of what people are looking for now.”

Sales of Bruegger’s new limited-time-only Sea Salt & Caramel iced coffee are off to a strong start, Kadylak reports. For summer, the chain will reprise its popular Coconut iced coffee for another LTO run.

Kadylak is one of the many marketers who know that iced coffee has a particular appeal for the often-elusive Millennial patron who grew up on cold, sweetened beverages.

In 2012, when the research firm Technomic asked consumers of various ages which beverages they were purchasing at restaurants or foodservice establishments more often today than two years ago, it found that 15 percent of consumers 18- to 34-years old were drinking more iced coffee or iced blended coffee made from scratch, compared to 11 percent of those age 35 and over.

“When you look at younger consumers, most of the coffee they are drinking is potentially of the iced variety,” Kadylak says.

With its ease of preparation, iced coffee is within the grasp of virtually any operator. There are several ways to go about it. Some operators use liquid coffee concentrate to make consistent iced coffees, lattes and mochas without an expert staff or specialized equipment. Others produce iced coffee with particular characteristics via methods that require a more practiced hand.

Championing the so-called Japanese iced coffee method is Pinewood Social, an establishment in Nashville, Tenn., that combines a coffee bar, liquor bar and full-service restaurant. This method brews hot java directly over ice in a holding vessel. The amount of ice replaces half of the water that would ordinarily be used in standard brewing. The resultant brew is cool, complex in flavor and at the proper strength.

“We brew it hot, so we extract all of the great aromatics and flavors as well as some of the acids and sugars in the coffee,” says coffee manager Nathanael Mehrens. “In our opinion, this is the best way to do specialty iced coffee because it keeps the full expression of the coffee.”

Others, just as opinionated, favor the cold brewing method. For instance, at Plenty Café in Philadelphia, the house’s five-bean espresso blend coffee is steeped in cold water for about 16 hours. 

“Cold brew coffee is extremely smooth because the coffee has not been in contact with really hot water,” says Plenty Café’s co-owner Anthony Mascieri. “It is also low in acid, very rich and has a really chocolatey taste.”

Also vouching for cold brew is Stephanie Izard, executive chef/partner of Little Goat, a diner concept in Chicago, where cold water drips over ground coffee overnight. “It produces the flavor we want without a watered-down taste,” Izard says. “It also cuts the bitterness, which is awesome.”

Another hot button for consumers is the ease with which iced coffee can be customized with various flavors and additives or made into specialty drinks.

At Bruegger’s, Kadylak estimates that 80 percent or more of guests add cream and sugar to their iced coffee. At some stores that have full espresso bars, they can opt for shots of flavored syrup as well.

Pinewood Social is touting The World In All Its Youth, an iced latte made with a double shot of Guatemalan coffee, sarsaparilla and chicory syrup and muddled fresh mint, plus a spring of mint for garnish. An iced coffee soda is in the works — a carbonated concoction of brewed Guatemalan coffee and Demerara sugar syrup that will be served via a beer tap.

“It’s light and refreshing and slightly sweet, but it still has that nice coffee flavor and aromatics,” Mehrens says.