Led only by Johanna's vision and their shared work ethic, the Cormans tapped into an untapped demand for grownup, sophisticated non-alcoholic drinks -- both by customers who don't drink alcohol and foodies who want interesting drinks.

Customers told them, "We've never been able to go out to a bar and actually feel like we're having a nice drink too," said Johanna. "We always get seltzer with cranberry or something like that."

Although it appeared to come out of nowhere, Vena's was really an outlet for old-timey cooking and canning recipes Johanna had been tinkering with for years.

She had found mention of apple syrup in an old cookbook while running the family apple farm in nearby Hiram, Maine, and she decided to try to create it from excess apple cider they made on the farm. (Her brother Billy Johnson is now the third generation of the family running Apple Acres Farm, but the family has lived in Maine for 11 generations, since before the American Revolution.)

"Two months later, we bottled it, we corked and waxed the top," Johanna said. "We're at the old Portland public market and within an hour, people were coming to, we're just selling tastes and bottled. Two or three people said, 'Okay, we want to be your distributor. We want to sell this all.' Within an hour!"

That's when she invented her first drink, the cider smash, around 1989. Now a Vena's best seller, it's "equal amounts of cider syrup, fresh lemon juice and bourbon," she said. "It's the easiest cocktail in the world, and tart, sweet, beautiful."

For Vena's booze-free bar, Johanna wanted real ingredients, no artificially flavored anything, whether she made the products in her commercial kitchen or bought them from the few producers making bitters, shrubs (drinking vinegars) and syrups that she liked.

Some of the drinks harkened back to another era.

The first drinks the Cormans developed were reminiscent of old-fashioned soda fountains: the lime rickeys, now in four flavors, and chocolate and cherry phosphates.

They also wanted created their own unique concoctions, like the Love Potion Number 9, made from raspberry gomme (an old-fashioned syrup), rose simple syrup, squeezed lime juice, Bolivar bitters, ghost pepper extract and seltzer.

Ginger Julep was made from muddled fresh mint, ginger puree, ginger syrup, ginger bitters, smoky habanero bitters, ghost pepper and seltzer.

Steve became Vena's head bartender, learning about mixology via YouTube videos, nailing those 10 drinks in his first few months on the job.

Part art and part science, the couple created and discovered ingredients to play with and invented new drinks. If they did well, they got added to the menu.

"One of the first we came up (around Valentine's Day 2014) with was the Lumberjack Love," she said.

They found a pine syrup made from this little company out in Colorado "that we just died over," which they turned into a best-selling piney lemonade.

These days, Steve leads the bartending staff. He works with more than 200 bitters and 30 shrubs to invent new drinks, trains Vena's staff, and leads classes to train bartenders and home enthusiasts of what they call liquid alchemy with bitters.

Johanna focuses on inventing and producing syrups and other products in her tiny commercial kitchen and developing Vena's retail operations. Next to the bar, Vena's sells ingredients for people to make their own drinks at home, including Johanna's own bitters and dry mixes that don't break US airport security liquid rules.

It wasn't always a sure thing that they would survive, but after more than a year into the business, a man walked into their store and changed their lives.

He stopped by in November 2014, asking Steve, "What's your best non-alcoholic drink in your non-alcoholic bar?"

Steve made him a Lumberjack Love, which has spruce pine syrup, lemon, spiced tonic, Alpine Herb bitters, wormwood bitters, and Owl & Whale's persimmon bitters.

"After two sips, he's in love with this drink," Steve said. "He says, 'What's going on in my palate?' I said, 'I told you, it's the bitters.' I explained the bitters."

After he left, Johanna and Steve's phones starting buzzing with text messages.

The man was Food Network star Alton Brown, who was in town doing a show at Merrill Auditorium.

His Twitter followers had recommended that he visit Vena's. After enjoying his Lumberjack Love, he had tweeted out his love for the shop.

"He put Vena's Fizz House as one of his top eight tour stops on his national 2014 tour," said Steve. "Thank you, Alton Brown."

Another big decision was adding alcohol to the menu, but the alcohol infusion wasn't just their idea. It came from their customers, who kept tossing little bottles of liquor in their trash after spiking their drinks.

Steve, who had a rotating list of 40 different mocktail recipes on the menu, knew what to do next.

"The first thing I did was take every mocktail, and I knew, but I wrote down the alcohols that would go great, matched, and what other bitter am I going to add to or take away when I add in alcohol?" said Steve. "All of a sudden, I had already 120 mixed drinks using our non-alcoholic menu."

The Lumberjack Love became the grownup Lumbersexual, which has gin, pine, lemon, spiced tonic, alpine herb and wormwood bitters.

The Blackheart Mocktail turned into the Blackheart Cocktail with Maker's Mark bourbon.  It had the same ingredients as its non-boozy cousin with the same proportions -- plus bourbon.

Even the child-friendly (but sophisticated) Fluffy Fizz -- cherry juice, squeezed lemons, squeezed limes, orange shrub, simple syrup, and seltzer, topped with a good dollop of cotton candy -- can get grown up. Vodka turns it into a cocktail, with a few dashes of Vena's Bitter Charles.

"We had such a good following for the non-alcoholic drinks that we were afraid once we added alcohol, we would lose those people," Johanna said.

That didn't happen. "We'd get all kinds of people, usually it was in groups, where it might be two don't drink and five do drink," she said. "They were thrilled."

As teachers, they like to teach customers about all the ingredients they make and use. "Most people that come in don't know anything about bitters or all the tonics and syrups," she said.

"So we want it to be that they're 100% comfortable, not to be intimidated, and we want them to ask us questions. We want them to be able to make drinks at home."

That's why they sell ingredients and freely hand out recipes in person and via their website, including the one below.

1.5 ounces blackberry puree

0.5 ounces lime juice

0.5 ounces Vena's honey creme syrup

2 mint leaves

4 dashes SF Bitters Co. Boonekamp bitters

8-12 dashes Dram Apothecary Black bitters

2 ounces seltzer

1.5 ounces bourbon for the alcohol version

Shake with ice in a Boston Shaker. (Mint will be muddled with ice during this process) . Pour all without straining into a smaller version collins glass.  Add two ounces of seltzer, stir and garnish with a mint leaf and lime wedge.