FREEPORT – The dream of two brothers – one a potato farmer, the other a brain surgeon – has become reality with a shiny new distillery ready to transform humble spuds into premium vodka.

After months of work, taste testers will help Maine Distilleries LLC decide this week on the final formula that will be on store shelves within a matter of weeks.

At $31.99-a-bottle, the company is aiming for the top of the shelf, and its founders are confident that their Cold River Vodka can compete with the world’s best.

“We’ve been waiting for this moment for three years, and we’re ready to go,” said Bob Harkins, Maine Distilleries’ CEO. “We’ve done our homework. We’ve developed a good understanding of the process. Now it’s show time. It’s time to deliver.”

Cold River Vodka is part of a growing trend.

Just like boutique wineries and microbreweries before them, a new wave of small craft distilleries is taking root in the United States.

The number of those distilleries has grown from 15 a decade ago to 66 today. Most of that growth has come in the last five years, said Bill Owens, president of the American Distilling Institute in Hayward, Calif.

Some of the distilleries are attached to small breweries whose operators discovered that the wort, or mash, could be transformed with extra processing into vodka, gin or whiskey. Likewise, vineyards have focused on brandies and grappa.

Owens anticipates future growth akin to the vintners and small breweries that have blossomed in popularity since the 1980s.

“Now the spirits industry is going through this renaissance,” he said. “People will pay extra for quality, there’s no doubt about that.”

One of the biggest success stories so far is Tito’s Handmade Vodka, in Austin, Texas, which is now sold in 45 states. Another is St. George Spirits, which makes Hangar 1 vodka and St. George single malt whiskey in California.

Massachusetts has three success stories on Nantucket Island: Triple Eight Distillery, Nantucket Vineyards and Cisco Brewers.

In Texas, Tito Beveridge was an early pioneer when he incorporated in 1995 and sold his first case of vodka two years later. This year, he expects to sell more than 100,000 cases of Tito’s Handmade Vodka.

His vodka goes well in martinis, on the rocks, or straight up, he said. What makes vodka so popular is its versatility, he said.

“My whole opinion is, I don’t care if you drink it with Sunny D or Dr. Pepper, just as long as you’re drinking it,” he said.

Unfortunately, regulations and red tape make it harder for distillers than for vintners and brewers to get into business, Owens said. Wineries and breweries are largely regulated by states; distilleries are also regulated by the feds.

In Maine, it took three years for Donnie and Lee Thibodeau, sons of an Aroostook County potato farmer, to make their dream a reality.

Their goal was to add value to the potatoes that Donnie Thibodeau grows on his 1,200-acre Green Thumb Farm in Fryeburg, near the Cold River.

He and Lee Thibodeau, a neurosurgeon at Maine Medical Center, signed up two additional partners. Harkins, a former ski resort executive, was hired to run the business and Chris Dowe, a brewery consultant, was tapped to build the distillery.

What they created was Maine’s first commercial distillery. Unlike White Rock Distilleries in Lewiston, which creates its beverages from imported alcohol, Maine Distilleries oversees every aspect of the process from potato seedling to bottling.

The process is relatively simple.

The potatoes, already washed, arrive in 2,000-pound bags, Dowe said. Three to four bags are dumped into a 1,475-gallon kettle where the potatoes are boiled prior to the fermentation process. Later, the liquid goes through a 1,000-liter copper pot still and circulates three times through a 34.5-foot cone to reach a purity of 96.2 percent alcohol.

Water pumped from an aquifer fed by the Cold River is filtered and added to the alcohol. That, in turn, goes into bottles.

In between, there’s the artistry that gives the vodka its nuances.

Last week, Dowe was still tweaking the taste profile while perfecting vodka’s most elusive quality: smoothness. The latest version had a full body and pleasant warm sensation when swallowed, with just a hint of fragrance.

The final version should be on store shelves at Hannaford supermarkets and in liquor stores in Maine and New Hampshire within a few weeks, Harkins said. By Dec. 1, Cold River Vodka will be in Massachusetts, as well.

Among spirits, vodka remains the nation’s most popular, accounting for 26.7 percent of U.S. liquor consumption last year, according to the Distilled Spirits Council of the United States.