Call the number on the label of a Vital Energy drink and you'll get Michael Joseph's personal cell phone.

"If someone calls, we'll actually give them a free sample, just for taking the time to call," he says.

Joseph, 26, is CEO of Enertia Beverage, a local start-up company founded by three friends, all graduates of Pittsford Sutherland High School. Their debut product, Vital Energy, is being sold in 40 convenience stores, delis, pizzerias and gas stations around Rochester.

Sort of a cross between Vitamin Water and Red Bull, Vital Energy is noncarbonated water enhanced with vitamin B, vitamin C, caffeine and taurine, an organic acid used in many energy drinks.

"Energy drinks are obviously a product that's growing ... but they've been able to take the traditional energy drink and take a more forward-thinking view," says friend Adam Podlesh, a NFL punter for the Jacksonville Jaguars and fellow Pittsford Sutherland grad.

The idea for Vital Energy was born when Scott Baron, 23 — who also is a full-time accountant — found himself working late into the night during tax season and in need of a pick-me-up. He says he couldn't find a suitable alternative to coffee or carbonated energy drinks, neither of which he likes.

So in February, Baron, Joseph and Jacob Blish, 25, launched Enertia, despite the bleak economy.

"To some extent, it was the bad economy that helped us start it," Joseph says. "It was really hard (for Blish and I) to find a job, we felt restless at home, and it gave us that push we needed."

But the three had no idea where to start.

"We had no blueprint," Blish says. "When we started it, we thought we would just buy some ingredients and come up with it in our kitchens."

Instead, they hired a beverage formula company to create the drink and flavors.

But the entrepreneurs took a hands-on approach to selling their product, pitching it to each retailer that now carries it. And they continue to deliver Vital Energy out of the trunks of their cars.

Roxanne Armstrong, owner of the Park & Oxford Café & Deli, has already purchased a second order.

"They came in the store and said they were from Pittsford and just releasing the drink that day, and I was excited for them," she says. "And it's getting really good reviews (from customers)."

Eventually, says Blish, the trio would love to sell Vital Energy in a bigger store, like Wegmans. But without a distributor, that goal isn't feasible. The chain has 75 locations in five states, so it would be impossible for the business partners to deliver the product in their personal vehicles.

"It's a lot of work," Blish says. Getting a distributor "would take out the door-to-door part," so that he, Baron and Joseph could focus exclusively on marketing and sales.

For now, though, social networking sites like Twitter and Facebook have proved to be their best marketing tools, something these young, Web-savvy entrepreneurs have grown up with.

"As long as you put the time and effort into it, you can get out there," Joseph says. They've also been giving out free samples of Vital Energy at local college campuses.

By using the local angle to their advantage, these entrepreneurs hope the idea will help get Vital Energy into more stores around Rochester and, eventually, other areas.

"We want people to know who we are," Blish says. "We're just normal people from Rochester."