SAN FRANCISCO — Meet the new Willy Wonka: Timothy Childs is a former space shuttle technologist who's building a 29,000-square-foot chocolate factory on prime waterfront property on the Embarcadero. He stands in the factory's laboratory inspecting a sample of split-open cocoa beans, pointing out the ones that have been properly fermented and talking intensely about the hedonics of chocolate — as in the hedonistic sensation of eating it, how it melts in the mouth, when it starts to break apart, and the way in which flavors and sugars are released. "We're freaks about it," says Childs, chief chocolate officer (his official title) of Tcho.

He's not the only sweet tooth/techno-tinkerer with chocolate on the mind. In fact, Childs is one of a generation of new Willy Wonkas, a recent crop of American bean-to-bar chocolate makers who are building their own factories — sometimes their own machinery — and tracking down cocoa beans to transform them into bars of chocolate (also known as "couverture"), for eating and for making confections.

There's no mistaking these chocolate makers for traditional chocolatiers, who create confections such as bonbons and truffles. Instead of enthusing about ganache, they're wont to talk about cacao genetics, or the advantages of a roller mill versus a ball mill during chocolate refining, or the stability of certain types of crystalline structures in chocolate.

These entrepreneurs tend to be excited about a just-found piece of vintage machinery (say, a 1930s mahogany winnower) or the next shipment of beans from Bolivia. They're continuously experimenting with roasting times, for example, or with stone-grinding techniques. Or they're taking the extra steps (or leaps) to oversee the drying of their own beans or to press their own cocoa butter.

SETTING NEW STANDARDS

The result is an envelope-pushing variety of chocolate, some of which is on par with the chocolate from European producers that connoisseurs have long considered the standard.

"We haven't even seen how great chocolate can be yet," says Colin Gasko, owner of Rogue Chocolatier (a chocolate maker despite the word "chocolatier" in the name), who launched his Minneapolis company in November. "I don't think that anybody in the world making chocolate right now is making the best chocolate that can be. There's such tremendous potential."

Bean-to-bar is industry parlance for the complicated process by which cacao is turned into chocolate. The bean-to-bar process involves: roasting the beans; breaking them into small pieces called nibs and removing the shells (referred to as winnowing); grinding the nibs, usually with sugar, to form a chocolate paste; then refining and conching (very forceful kneading) to produce the desired smoothness and to develop flavors.

Depending on the chocolate maker's stylistic approach, the following ingredients might be added: vanilla, additional cocoa butter and/or soy lecithin. After it's tempered (heated, then cooled to a certain temperature, so that it has sheen and snap), the chocolate is poured into molds.

Until recently, the process was the domain of mass producers, even in the 12 years since groundbreaking Scharffen Berger started making chocolate in Berkeley. (And even the big companies increasingly are contracting out a significant part of the process.)

In the last couple of years, inventive chocolate makers have popped up across the U.S. In Brooklyn, a couple of cocoa-loving brothers are building a "chocolaterie and laboratory" in the south Williamsburg neighborhood. Childs teamed with Wired magazine co-founder Louis Rossetto to form Tcho, refurbishing equipment shipped in its entirety from an old chocolate factory in Wernigerode, Germany. Tcho is a 21st-century chocolate factory: Childs plans to install video monitors and display screens that show what's happening inside the machines.

Tcho, which has sample chocolate "in beta" and is set to open in the first quarter of next year, is among the biggest of the new wave of chocolate makers, with 18 employees and with the capacity to make three tons at a time. "That's still less than what the big guys spill during a shift change," Childs says.

Artisanal "micro-batch" producers are coming out with 50 to 1,000 pounds at a time, with just one or two people making the chocolate, such as Art Pollard of Amano Artisan Chocolate in Orem, Utah; Steve DeVries of DeVries Chocolate in Denver; Alan McClure of Columbia, Mo.-based Patric Chocolate; and Gasko's Rogue Chocolatier.

BIGGER APPETITE, CACHET

Now "there's more interest in chocolate and there's high enough prices for chocolate to make it feasible to have a small company," says DeVries, a former glass manufacturer who pursued chocolate making after a trip to Costa Rica several years ago and his first encounter with a cocoa pod. On subsequent trips, he started bringing back as much as 70 pounds of cocoa beans in his suitcases. (He might be the Charlie Papazian of chocolate makers, Papazian being the patron saint of microbrewing.)

Other bean-to-bar chocolate makers include Theo in Seattle; Mast Bros. Chocolate in New York; Taza in Somerville, Mass.; and Askinosie of Springfield, Mo.

"It's a very courageous choice (to make chocolate), especially for the small processors," says international chocolate consultant Chloe Doutre-Roussel, who wrote "The Chocolate Connoisseur" and recently has been helping a cacao cooperative in Bolivia launch a chocolate bar for the export market. "It takes quite a lot of investment in machinery. Even those with small machines end up buying bigger ones. Plus you need to pay for trips to buy the beans and to ship them."

What formerly might have been seen as the unglamorous side of the chocolate world now has cachet, Doutre-Roussel says. Famed chocolatiers such as Pierre Marcolini or Patrick Roger in Belgium and France didn't make their names by roasting and grinding beans. But it has become trendy for high-end European chocolatiers to make at least a limited amount of their own chocolate, maybe even from their own small, vanity-project cacao plantations. Still, Europe hasn't seen the rapid rise of chocolate makers that has taken place in the U.S.

"Three years from now, we'll probably see double the number of chocolate makers (in the U.S.)," Childs says. "It sounds banal, but it reflects back to the Internet and technology. Before, it was so hard just to have communication with growing areas. Now, practices get communicated, contacts established, samples and feedback are sent. Sourcing the cocoa is the hardest thing to do. Making it is second-hardest."

Childs notes that there's enough information on chocolate-making Web sites to "let people make it on their own and find people who can help them. We couldn't do this 10 years ago; we couldn't do this five years ago."

'I WAS CURIOUS'

Meanwhile, by the time Hershey Co. bought Scharffen Berger in 2005 and then Portland, Ore.-based Dagoba the following year, the gap left by industry consolidation was ready to be filled. In 2006, Joseph Whinney founded Seattle-based Theo, the first roaster of organic and fair-trade cocoa beans in the U.S., according to its Web site.

Many bean-to-bar producers say they're motivated by the possibilities for tremendous change in chocolate making as new machinery affects the development of flavors.

"I was curious," DeVries says. "How could it be that I could grind this stuff in my kitchen and have more complex chocolate than any I'd ever had before?

"We have so much upside now. If the French bought all their grapes in shiploads from Africa, how good would the wine be? That's about where we are with chocolate."

Back in the factory lab, Childs points to photos of neatly boxed fermenting cocoa beans (as opposed to beans fermenting in large piles). Tcho plans to implement "infield improvements and models for fermentation and drying," Childs says. "That's the first order to improving quality and flavor. I'm looking at this not just from bean to bar but from pod to palate. Pod to bean is the most crucial step in the process."

DeVries oversees his own drying method. "For me to make chocolate, I need to go there, be involved in the harvest and be involved in the drying," he says. "I'd heard about the drying of beans in Chuao (Venezuela, where prized beans are from), went down and learned how they made the stuff. A lot of it was the way it was dried. I started doing experiments in Costa Rica and dried them very slowly. I got fantastic chocolate — dried-fruit tones that just knocked people out."

WONKA TOYS

Transforming the beans to bars takes machinery — lots of it. It's the myriad fascinating, sometimes-obscure and hard-to-find, oft-modified machines that charm the Wonkas — small grinders originally used for making batters in Indian cuisine, such as for dosas (rice-flour pancakes), melangeurs (grinders) tracked down in Spain, a conch from the Suchard factory in Switzerland, or a winnower salvaged from Scharffen Berger's parking lot.

"It's not all easy to find. Machine-shop skills come in handy," says Amano's Pollard, a search-engine developer who had his first chocolate epiphany 11 years ago during his honeymoon after eating a Belgian chocolate truffle. "I decided to design and build my own refiner and conch from scratch. I think one of the great things about doing it the hard way instead of buying machinery is that you really learn why things are the way they are."

The level of attention that the bean-to-bar guys pay to each part of the process is sort of captivating. During winnowing, much of which Patric's McClure does by hand, he removes a large proportion of the germ because, he says, it's hard and bitter. Rogue's Gasko, who, he says, "started fooling around with machines in the basement," says he's working on equipment that he hopes will get the remaining hulls down to one-tenth of a percent with only 2 percent loss of the nib and at the same time remove all of the germ. "It requires a bit of engineering," he says.

As for ingredients, some of the new chocolate makers have little interest in anything but the cocoa beans and sugar.

The only two ingredients you'll see listed on the packaging of DeVries' chocolate is cocoa beans and cane sugar, but he doesn't describe himself as a purist. For now, he says, "I'm still trying to figure out what's going on with the cocoa bean."