Q: Should I worry about hexane in soy burgers and other processed soy foods?
A: Probably not, though it’s hard to know for sure. Hexane is a volatile solvent that’s used, with Food and Drug Administration (FDA) approval, to extract oil from soybeans (as well as from nuts and olives). Most soy protein ingredients in meat analogs and nutrition bars, which are listed on labels as soy protein isolate, soy protein concentrate or textured vegetable protein, have undergone hexane processing.
Hexane is classified as an air pollutant by the Environmental Protection Agency (EPA) and as a neurotoxin by the Centers for Disease Control and Prevention (CDC). Chronic exposure to hexane in factory workers has been linked to some neurological conditions, but it’s unclear whether consuming trace residues long term is a health hazard. It’s even unclear how much hexane, if any, remains in the food after processing, because the FDA does not monitor hexane in foods, nor does it require companies to test for it.
According to the Soyfoods Association of North America, hexane is used only in the initial steps of soy processing, and virtually all of it is eliminated by the time the soy ingredients are incorporated into soy burgers and other products. Testing by Swiss scientists found that the majority of vegetable oils sampled had no detectable levels—and those that did fell below the tolerance limit set by the European Union.
On the other hand, independent testing commissioned by the nonprofit Cornucopia Institute created a stir a couple of years ago when it found hexane residues in soy oil, as well as in soy grits and soy meal. Since its report, several companies have switched to safer and more environmentally friendly hexane-free soy protein ingredients.
What to do: If you want to avoid hexane-treated soy foods, look for “100% organic” products with the United States Department of Agriculture (USDA) seal, since hexane is banned in organic food production. A label that just says “made with organic” ingredients is no guarantee that all ingredients are hexane-free.
Better yet, buy soy foods made from whole soybeans—such as tofu, tempeh, soy milk, and soy yogurt—since they do not typically undergo hexane processing and are generally healthier for you, too. Whole soybeans (edamame) are always a hexane-free and healthy option. Expeller-pressing and cold-pressing are physical methods to extract oils that do not involve solvents, so soy and other vegetable oils produced in this manner are also hexane-free.