It’s said that necessity is the mother of invention, and that seems especially true for Hint Essence Water. The product was created by former America Online executive and mother of four Kara Goldin, who says she got into the beverage business because she was searching for something she would feel comfortable buying for both herself and her children.

“I was looking for a beverage that would keep me hydrated, that didn’t have all of the sweeteners, whether they be sugar or artificial sweeteners,” she says.

Goldin says she pitched the idea of an unsweetened water flavored with fruit essence to existing beverage companies, but when she was turned down, decided to launch the product on her own. She enlisted her husband Theo, a former Netscape executive, to serve as Hint Inc.’s chief operating officer, and says the idea went from concept to market introduction in nine months.

“My gut was that there was a market out there for this product, so I would just develop it,” she says.

Based in San Francisco, Hint Inc. now carries 10 flavors of “essence” water in varieties such as Pomegranate-Tangerine, Raspberry-Lime, Peppermint, Pear, Cucumber, Tropical Punch, Lime, Apple, and new Mango-Grapefruit and Strawberry-Kiwi.

While the product originally was intended to be a children’s drink, Goldin says the company quickly decided to make it an all-ages beverage. “Today, we don’t label things as ‘kids’ separately because we don’t want to be in the business of deciding which flavor adults like and which flavor kids like,” she says.

“If you look at most beverages that are targeted at kids, they’re highly sweetened, whether that’s with some variant of sugar or concentrated fruit juice or an artificial sweetener,” Theo adds. “They’re all pretty powerful-tasting sweet things, but that’s kind of an artifact of what people have been doing more than what you can get kids to drink ... [Hint is] targeting a fairly sophisticated taste profile, but it’s a mistake to underestimate what kids will do.”

Hint was not Kara Goldin’s first foray into start-up companies. She started with AOL during its beginnings, and served as vice president of shopping and e-commerce partnerships. She says creating Hint was driven by a similar desire to develop a solution to a need. “It’s very similar to how I felt back in the early days of AOL and the Internet. I felt like this was something that definitely needed to happen. Somebody needed to go and do it.”

It didn’t take long for the small start-up to attract the attention of some big-name partners, including The Walt Disney Co. The entertainment and media giant contacted Hint last summer as part of an effort to associate its brand with healthy food and beverage companies. The first collaboration between the two companies was a promotion for Disney’s holiday film “The Santa Claus 3: The Escape Claus.” Hint featured the movie’s star, Tim Allen, on bottles of its Peppermint-flavored water, and ran an online promotion that gave away tickets to the film.

The companies teamed up again for last month’s release of “Meet The Robinsons,” with a similar tie-in on bottles of Hint’s Raspberry-Lime flavor, and will partner on promotions for the upcoming “Ratatouille,” “Underdog,” and the second edition in “The Chronicles of Narnia” series.

Like most start-up companies, however, the bulk of Hint’s marketing focuses on special events, especially the ones through which it can make some sort of social impact.

“We feel strongly that if you’re going to spend money around marketing, that money ought to do something good for people,” Theo says. “Most of our marketing efforts and dollars are directed toward supporting charitable organizations.” The company has given away product at fundraising walks for AIDS and diabetes as well as golf tournaments benefiting leukemia research, and has an ongoing relationship with Cure Autism Now, an organization devoted to making the lives of families dealing with autism more manageable.

“It gives people an opportunity to try our products in a great context where they’re outdoors on a nice day, feeling good about the fact that they’re contributing to a cause that’s important to them,” Theo says. “That’s a great time for them to try something new.”

As newcomers to the beverage industry, both Kara and Theo Goldin say they still are learning the distribution ropes. The product first launched in the natural foods channel and specialty stores, and has moved to up-and-down-the-street accounts as well as some hotels.

“Even after you get distribution, it’s still a store-by-store sell,” Theo says. “There are a lot of people in that system who need to be convinced and onboard and reminded of how great the product is on a regular basis.”

With two Internet backgrounds in the family, Hint was able to cover gaps in its initial rollout with online availability. “We do a significant business online,” Kara says. “We did it because to get distribution in traditional stores was a much longer process than we had ever imagined or what we were used to working in. Internet speed is so much different than the food and beverage industry.”

But surprisingly, Internet marketing is not a big part of the company’s overall strategy. “We put a lot of work into our Web site to make sure our presence on the Internet was professional, informative, clear and easy to use. But our focus really is on the distributors and retailers that generate the bulk of our business, and doing marketing in the physical world,” Theo says.

As part of the ongoing evolution of the brand, Hint is readying a new bottle for rollout that will allow it to scale up production for future growth. The new bottle is slightly taller than the original but maintains the transparent labels and graphics. “It’s something that will allow us to grow as we head toward summer,” Theo says.

Although it has only been in the beverage business for two years, Hint doesn’t intend to stay in one place for long. As is apropos to her brand, Kara Goldin will only hint at future opportunities, but says: “We think there is a lot of work to be done in this industry. We have a lot of great ideas and we’d love to see Hint be extended in a lot of different categories.”