Impossible Burgers. Photo by ANGELA WEISS/AFP via Getty Images
AFP via Getty Images
The Food and Drug Administration (FDA) has issued a notice that rejected the objections from the Center for Food Safety about the safety of genetically engineered soy leghemoglobin. Impossible Foods, Inc., which uses soy leghemoglobin in its vegan Impossible Burgers, already sells its products in grocery stores and restaurants.
What Is Soy Leghemoglobin?
According to Impossible Foods, soy leghemoglobin stands for legume hemoglobin and is a protein that contains heme. Heme, the molecule that carries iron in plants and animals, is responsible for the color, texture and taste of meat.
“We make the Impossible Burger using heme from soy plants, which is identical to heme from animals and gives Impossible its uniquely meaty flavor,” Impossible Foods said.
Soy leghemoglobin is one of two genetically engineered ingredients in Impossible Burgers. (The other genetically engineered ingredient is soy protein.) The company makes soy leghemoglobin by engineering yeast that has the gene for it. A simplified explanation of the process is that they insert the DNA for soy leghemoglobin into yeast, grow yeast through fermentation, isolate the soy leghemoglobin and add it to the burgers.
Impossible Foods points out that their process eliminates the need to harvest actual soy plants to get heme from their root nodules, which means their method is more sustainable. The company also shares that it has done “rigorous testing, including a stringent rat feeding study” that did not find any side effects from eating soy leghemoglobin.
The Center for Food Safety’s Objections
The Center for Food Safety (CFS), a nonprofit public interest and environmental advocacy organization, has filed objections to the FDA’s approval of genetically engineered soy leghemoglobin (GMO heme) as a color additive. The CFS has also objected to Impossible Foods selling its products in grocery stores before the FDA replied to its initial questions.
“CFS objects to the approval of the new color additive petition for GMO ‘heme’ because (1) FDA did not require testing of the raw product or the genetically engineered yeast; (2) FDA’s approval will allow GMO ‘heme’ to be used in new cell-based products without additional testing; (3) the product is not properly labeled; and (4) FDA failed to satisfy the “convincing evidence” standard that applies for approval of new color additives,” CFS said.
CFS points out that the studies supporting the safety of genetically engineered soy leghemoglobin included authors who work for Impossible Foods, which is a conflict of interest.
The Food and Drug Administration’s Response
The FDA has responded to CFS’s objections and has upheld its decision to consider soy leghemoglobin safe for use as a color additive and exempt from certification. In a final rule document, the FDA has shared that Impossible Foods addressed the safety of soy leghemoglobin, yeast protein is not a major allergen, and additional studies by the FDA are not necessary. This means that the company can continue selling Impossible Burgers.