(FORTUNE Magazine) – When a waitress toting an orange-rimmed coffee carafe approaches, caffeine addicts automatically know they should cover their cups. But how exactly did orange become synonymous with decaf?

It started in 1923 when Sanka, the first decaf coffee, hit the shelves bearing a distinctive orange label. General Foods (now part of Kraft Foods) bought Sanka in 1932, then created an instant version during World War II coffee rationing. To promote the brand, the company provided Sanka-orange coffeepots to coffee shops and restaurants across America, says Bill Teller, a spokesman at Bunn-O-Matic, a leading coffee-equipment maker.

"For years Sanka was a household word for decaf," says Ted Lingle, executive director of the Specialty Coffee Association of America. As demand for the lighter brew grew, competitors developed decaf beans for making fresh coffee. When marketing the Joe, the newcomers, says Lingle, simply "followed Sanka's color scheme." --Julia Boorstin