If you’re a drop of Salute Santé! grapeseed oil being cooked in a Napa Valley restaurant, chances are you will meet your maker.

Rather than being picked up by a waste collector and shipped off to a landfill, you will find yourself once again in the presence of your creators — Nanette and Valentin Humer. But, this time, rather than being sealed inside a long-necked boutique bottle, prepare to be pumped into the Humers’ gas tank. That is, the grapeseed oil tank of one of their vehicles.

The couple’s latest green endeavor has been to convert their three company vehicles to run on grapeseed oil after it’s been fried up, sauteed, scalded or simmered at one of several local restaurants. So far Valentin Humer has arranged with Julia’s Kitchen, Silverado Resort and Zuzu to pick up their waste oil — a win-win he says, because the eateries no longer pay to have the used grease carted away, and Humer gets free fuel.

The idea behind filling up on their waste grapeseed oil is to further “close the loop” — eco-speak for relying on energy already within a system by recovering resources that would otherwise be wasted.

“We pick up the old oil at the restaurants as we drop off a new shipment,” said Nanette Humer, gesturing to two early 1980s Mercedes Benzes and a robust F350 turbodiesel Ford truck — all diesel engines.

The conversions of all of the diesel engines were performed by local mechanics and essentially involved installing some extra tubing and a special filter designed to catch any lingering food debris before the grapeseed fuel reaches the engine.

Converting an engine — it must be a diesel engine — to run on any kind of vegetable oil usually costs $2,000-$3,500. The Humers’ turbodiesel Ford truck is so massive it requires some diesel use to warm up the engine before the driver can switch over to the grapeseed oil tank.

The Humers believe the grapeseed oil is probably healthier for their cars, and less likely to clog its “arteries,” since it’s the lightest known cooking oil.

“You are what you eat,” said Valentin Humer, the president of Food & Vine Inc. the company that manufactures the Salute Santé! grapeseed oil.

The couple attained certification as a green business for their company from the Co-op America Business Network. They said converting the cars to run on waste grapeseed oil is the latest in an ongoing push to reduce their environmental impact.

A goal is to harvest grapeseeds closer to home, from large grape producers in the Central Valley and the Napa Valley, to cut back on fuels needed to transport the seeds and final product. Since its inception 12 years ago, Salute Santé! has collected most of its grapeseeds from Italy and France, some of the largest grapeseed producers in the world, according to Valentin Humer.