OnTap offers two flavors, Pale Ale and American Ale.
Craft beer continued to post double-digit growth even in the depths of the recession, as many consumers saw the $8 or $9 they spent on a six-pack an affordable luxury.
But what if you didn't have to spend extra to get what some consider a better-tasting brew?
According to a Colorado start-up, its liquid flavor enhancer, called OnTap, gives beer drinkers the taste of craft without the added cost.
Just drops of OnTap will lend a craft-beer taste to any domestic light lager, according to CEO Solie Swan. One bottle of OnTap, which retails at $3.99, can change the flavor profile of 18 standard 12-ounce beers.
"It's roughly a third cheaper" than the average craft six-pack, Swan said.
OnTap offers two flavors, Pale Ale and American Ale, but while the sales pitch says "craft beer," Swan said the craft beer aficianado isn't necessarily his target consumer. Rather, OnTap is looking for 21- to 34-year-olds who regularly drink domestic light lagers but may be ready to try something else.
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"We hope to reach 1 percent of the market that's buying the 100 million barrels of domestic beer every year," Swan said. "If we can reach 1 percent, it will put us somewhere in the $35 million to $40 million range."
This type of item has been used with nonalcoholic beverages. MiO, which Kraft Foods launched in 2011, has been a huge success as a flavor additive for water, with media reports suggesting sales of more than $200 million. Kraft plans to follow-up with a similar product under its Crystal Light brand.
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Just what is in OnTap?
"It's a mixture of natural and artificial flavors, and we worked very closely with a flavor house in New Jersey called Flavor Dynamics to come up with the ingredients," Swan said. "I worked with them for about a year to develop the flavors. We have the two out right now, and we're working on a couple of other flavors like honey beer and cider."
The drops are also free of calories, carbs, gluten and alcohol, according to OnTap.
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The initial response has far exceeded the company's expectations, Swan said, though he acknowledged skepticism among those who haven't experienced OnTap.
"Will everybody like it? No-we never expected that. Will others like it? Absolutely," he said. "It gives people, especially those who typically only drink domestic lagers, a lot more options than they have right now."
-By CNBC's Tom Rotunno. Follow him on Twitter @TomRotunno.