Improve on Nature

‘Cork is random,” observes Michael Friedman, CEO for Oneo Closures North America. “It’s a plant. When you punch a cork out of a piece of bark, it’s very unusual to get one that’s absolutely perfect, with no veins and no lignine. That’s the part of cork that’s less desirable — it’s harder, doesn’t have the same elasticity, and is less able, mechanically, to come back into shape” after it’s been deformed. (It’s this elastic character, and the tendency for cork to return to its original shape, that make it such an effective stopper: the compacted cork is forever straining to expand to its original size, pushing against the neck of the bottle and creating a tight seal.) “What you’re looking for is called suberine — the spongy, elastic, semiwaxy fiber in cork.”

A little less than 20 years ago, says Friedman, Oneo came up with a solution — art perfecting nature. “We grind up the cork into 2-millimeter particles and put them on a densometric sorting table — it’s basically a giant Shaker table. It takes the lighter stuff — the suberine — and moves it over to one side and moves the other stuff away. We actually burn it to generate power for our plant. Then we put the granules into individual molds and, using a food-grade binder, put them back into a cork shape.” It’s not a perfect process — a little more art is called for. “When you put the cork back together, you end up with gaps between the granules. We fill those with microspheres. They’re made for us in Sweden — polymers filled with an inert gas. When they’re heated and put under pressure, they expand hugely and fill those little gaps in the cork.”

And by varying the proportion of cork to microspheres, “We can determine exactly what the permeability of the closure will be — how much oxygen can permeate the closure over a given period of time. (With an actual cork, if you have one little vein or structural defect, it could allow oxygen to just get in randomly.) Right now, for wines that are intended for immediate consumption, we have a cork with lower levels of microspheres, allowing more oxygen exposure. And we have a very tight cork for longer-aging wines. The right amount of oxygen over the right amount of time is your friend.”

Micro-agglomerate corks like this also aid in the fight against TCA — the cork-borne compound that causes cork taint in wine. According to Friedman, “You cannot use steam effectively on a punched cork, because it deforms it to the point where it’s mechanically unable to be a cork.” And steam is the most effective way to remove the chemical components that may combine to form TCA. Or, at least, it was.

“Our director of research and development comes out of the food world,” explains Friedman, and it was in that world that Oneo found its answer: supercritical fluids. “Basically, if you have something like water or carbon dioxide under very high temperature and pressure, you get this state that’s sort of between a liquid and a gas. It becomes a solvent.” (The Oneo literature puts it this way: “It has the unique ability to diffuse through solids like a gas, and dissolve materials like a liquid.”) “This process has been around for many years,” continues Friedman. “It was used in the ’30s to concentrate flavors. In the ’60s, the Russians were using it to extract essential oils. Then, in ’67 or ’68, Nestlé started using it to extract flavor characteristics from coffee to add back into decaffeinated coffee. It’s also used to remove the bitter components from hops in high-end beers and for extracting fragrances from flowers for perfume.”

Oneo’s idea was to use it to remove potentially damaging chemical compounds from cork granules. “We worked with the French Nuclear Atomic Energy Commission to develop protocols for this — they have a facility called the Fluid and Membrane Lab. We just needed to adapt an existing process.” The result was the DIAM cork, “the only cork closure available on the international market today which is guaranteed to have TCA at levels below the detection thresholds of one half of one part per trillion.” Now, “We have our own plant in Spain, on the same site as our traditional cork-processing plant. We take the granulated cork, process it through the supercritical carbon dioxide cycle, and pump it back to our traditional facility,” where it gets molded into shape.

That’s where Friedman comes in. Oneo wanted some help in selling DIAM to the world, and they decided he was the man to help get the job done. Friedman, for his part, liked what he saw. “I’ve always been around brands,” he explains. “One of the things this company invented years ago, without really understanding that it had done so, was the idea of putting their name on a cork. Taking an agricultural commodity and putting a name on it, because there’s a technical advantage to it, the process by which it’s been made. As a marketing guy, I found that very interesting.”

For starters, Friedman ramped up the company’s emphasis on the DIAM brand, pulling Oneo’s screw-cap closures from the U.S. market and scrapping conventional cork production altogether. Then he set about working his contacts. “I’ve been in the wine business for 30 years. I was a general manager at Fetzer for 7 years, and before that, I ran the import business for the parent company, Brown-Forman. I have relationships at pretty high levels of major wineries, and I’m tapping into those relationships, building programs to design specific protocols for them. One of the largest wineries has asked us to develop a custom version of the DIAM cork, one with a specific degree of permeability. Another wine group owns 29 brands and 12 wineries, and we’re now in half their brands. London is the largest export wine market in the world, and we are the dominant closure there. Tesco is the number-one wine retailer in the U.K., and the only approved closures in Tesco are screw caps and DIAM corks.”