Just call him Jam Boy. Fraser Doherty doesn't mind a bit. In fact, he encourages it. Doherty, a boyishly charming Scot with a brogue to match, is the jam darling of the U.K.. And he has a kitchen-to-grocery-store-shelf story that we're more accustomed to hearing from middle-aged women than from fresh-faced teens (although it's worth noting that he's not the only entrepreneur on our list who turned a family recipe into a thriving business; see our profile on Joe McClure).

Doherty learned to make jam from his grandmother (his "Gran", as he calls her) when he was 14 years old. Two years later, he decided to take a stab at commercializing the product. He studied the market and decided that a healthy offering could do well. He fiddled with Gran's recipe to eliminate added sugar, and use 100 percent fruit and fruit juices. "Jam sales in the U.K. had been in decline because it was so unhealthy," says Doherty. "There hadn't been a new brand in the category for a long time."

Doherty's big break came when he met a buyer at Waitrose, a major supermarket chain in Britain, and tentatively sold him on the idea. He then lined up a factory. At every step of the way, his age prompted skepticism. "I was a teen with no money and no experience, so most people rejected me," he recalls. "But then I finally convinced a jam facotry to work with me and we figured out how to produce the recipes that I had developed in my parents' kitchen on a big scale." He also hired an ad agency, which came up with a comic book-like brand identity for the product.

Doherty eagerly returned to Waitrose with the fruits of his labor. "They thought the labels were silly, the factory I chose was too expensive, and they didn't like the flavors," he recalls.

But Doherty was a resilient lad and he went back to the drawing board. He brought costs down by signing on with a new factory that put up 100,000 pounds in working capital for the jars, fruit, and credit for his customers. And he asked his ad agency to completely re-craft the brand strategy for a more homespun look. This time, Waitrose gave SuperJam the thumbs up and the product launched in Edinburgh in March 2007. "They sold 1,500 jars of jam in one day," says Doherty, "which is more jam than they would usually sell in a month."  Now, SuperJam supplies more than 1,000 supermarkets in the U.K., including Tesco and Asda/Wal-Mart; Doherty hopes to expand to more countries in Europe and to the U.S. within the year. He's in preliminary discussions with Whole Foods.

A slew of honors for Doherty followed SuperJam's launch, including a Global Student Entrepreneurship award, dinner with Gordon Brown at Downing Street, and a place for SuperJam in the National Museum of Scotland as an "Iconic Scottish Brand." But Doherty is most proud of a philanthropic initiative that he launched a year and a half ago. He sponsors free "SuperJam Tea Parties" with live bands and dancing for the elderly; so far, there have been 120 events, some with up to 600 guests.

Gran would be proud.