Milk's not just for breakfast anymore. Fueled in part by bundled kids' meals at QSRs, milk is gaining in lunchtime sales.

A nutritional workhorse, milk delivers calcium, protein and several essential vitamins. Adding to its allure for operators is the fact that milk already is on hand in most foodservice kitchens. The trick is to sell customers on the modern-day appeal of an old-school choice.

At restaurants overall, milk servings have increased across all dayparts over the past five years, according to research by Port Washington, N.Y.-based The NPD Group. Growth is strongest at lunch (13%), compared with a rise of 6% at dinner and 2% at breakfast. Adding cachet for adults and kids alike can be done simply: Expand flavor options; build milk flights of different varieties and flavors; add creative steamed-milk drinks; and adopt more-appealing single-serve packaging.

Dublin, Ohio-based Wendy's knows how to make the most of the beverage. The quick-service giant has offered low-fat white and chocolate milk with its kids meals since 2004 and now sells 40 million single-serve bottles per year. To further boost the products' appeal among parents seeking healthful selections for their children, the chain recently introduced 1%-fat white milk fortified with extra vitamin A, vitamin D and calcium.

Meanwhile, at Milford, Conn.-based Subway restaurants, customers in some markets can opt for strawberry milk in addition to standard white and chocolate varieties.

“Adults are buying it, too,” says Subway spokesman Les Winograd, noting that the restaurant's menu offers 12-ounce bottles instead of the 8-ounce containers available at most quick-service operations.

For operators that don't typically offer bottled drinks, flavored syrups in regular and sugar-free varieties make it easy to expand milk choices. That's what servers at The Purple Café and Wine Bar in Seattle, Kirkland and Woodinville, Wash., use to mix flights of chocolate, caramel, strawberry and white milk. The restaurants charge $5 for the samplers, which come in glasses perched in the same wrought-iron holders used for wine flights.

“It's very contagious—you'll see one table of kids get it, and when the other kids see them come out, it snowballs,” says David Yusen, Purple's director of marketing.

At Daily Grind Unwind, a 55-unit coffee chain based in Winchester, Va., each store has as many as 20 syrups on hand to use in flavored steamed-milk drinks dubbed Steamers. The majority of customers order theirs made with whole milk—the standard preparation—but skim and soy milks are becoming more popular, says co-founder Ed Chapman.

He says that teenagers are the biggest audience for the Steamers, which account typically for 5% to 8% of a store's sales but which can jump to 35% of sales in college towns. Vanilla, chocolate, caramel, raspberry, strawberry and hazelnut are the most popular flavors, but pomegranate is gaining ground.

“Steamers give people who aren't into coffee a nice coffee-shop drink they can enjoy and still feel hip and trendy,” Chapman says.

Contact writer at aperlik@reedbusiness.com