She spent about six months reading up on how to make different spirits, discovering what type of equipment she would need, the length of time involved in the process and figuring out how to finance it. She also evaluated her target market and the overall market and was convinced there was a demand for it.
According to the research firm Marketline, the global alcohol drinks industry is expected to exceed $1 trillion by the end of 2014. Not to mention, it anticipates makers to be pouring out about 210 billion liters this year, alone. That's a 10 percent increase in five years. Firtle just had to decide exactly what she wanted to make.
"Rum was actually the first spirit that we distilled in the U.S.," she told CNBC. "It was really important to the history and economy of the colonies, and we haven't distilled rum in New York since that time."
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In 2012, she quit her high-paying hedge fund job and founded The Noble Experiment, her distillery in Brooklyn. The name is both a tongue-in-cheek nod to Prohibition and a title for this chapter of her life.
She poured her life savings into the project, sought out a few investors—including her former colleagues—and set out making her first batch of Owney's Rum. It's a white unaged rum named after Owney Madden, a Prohibition-era mobster and bootlegger.
She kept her costs low doing most of the initial bottling, selling and distributing herself with the help of family and friends. Two years into the operation, she's been able to hire two employees, gain a distributor and win several awards and accolades from the likes of Forbes, New York Magazine, the Rum Journal and the New York State International Spirits Competition.
—By CNBC's Mary Hanan