When professional athletes are hiding a secret, we tend to assume it's either a pending team transfer, an injury they've been nursing, or maybe a brewing tabloid scandal. According to an exclusive interview with British tabloid The Sun, Mathieu Flamini, a French midfielder for U.K. soccer club Arsenal, has been holding out on something a lot more interesting:

For seven years he's been helping run a company that's aiming to replace the oil we use in many of our everyday products. And he hasn't even told his teammates about it.

GFBiochemicals, which Flamini helped found with his friend and business partner Pasquale Granata, has just come out of stealth mode, announcing that it is the first company in the world that can mass produce levulinic acid, a bio-based chemical that could replace oil in everything from pharmaceuticals and agrochemicals to plastics and personal care. Biogasoline, biodiesel and jet fuel can also be produced from levulinic acid. In fact, says GFBiochemicals, levulinic acid has been named by the U.S. Department of Energy as one of 12 molecules that could replace oil in all its forms.

Already employing 80 people at its plant in Milan, and providing work to a total of 400 people, GFBiochemicals can apparently make levulinic acid from a wide-range of biomass feedstocks, meaning it can presumably make use of whatever excess biomass that happens to be most competitively priced in the market at the time.

Questions, of course, remain.

Low oil prices are putting the squeeze on many alternative energy sources — but most notably those that aim to directly compete with diesel, gasoline and other liquid fuels are being significantly impacted. Assuming Flamini started his investments when we were all fretting about peak oil, his economic calculations may look decidedly different now that gasoline is trading at under $2 a gallon here in the U.S. Similarly, the arrival of affordable electric cars and buses (not to mention the apparent wane in interest in driving among teens) suggests that liquid fuels are not necessarily the indispensable ingredient of modern life that they once were. And lastly, biofuels are only as sustainable as the sustainability of their feedstocks — so Flamini and friends will have to demonstrate a viable alternative to corn, soy beans or virgin forests.

That said, even the greenest of electric cars contains an awful lot of plastic. So it would be very cool indeed if that plastic was made efficiently from waste biomass, not oil. And we are a long way off from electric-powered international aviation, so a sustainable liquid fuel remains an important priority.

Let's hope that Flamini's venture succeeds. It's certainly cool to see a professional athlete putting his wealth to work for good.