Why you can’t buy the ‘bloody,’ meatless Impossible Burger in supermarkets


The famous “bloody,” plant-based Impossible Burger is now available at almost 5,000 restaurants in all 50 states. But that very appearance of bloodiness may have presented another regulatory hurdle for the company and its effort to get the product into supermarkets.

Impossible Foods, the Silicon Valley maker of the eponymous burger, uses genetically modified yeast to mass produce its central ingredient, soy leghemoglobin, or “heme.” It’s heme, the company said, that gives the Impossible Burger its essential meat-like flavor.

The substance was ready to break out this summer after the U.S. Food and Drug Administration, following years of back and forth, declined to challenge findings voluntarily presented by the company that the cooked product is “generally recognized as safe,” or GRAS. Such a “no questions” letter means the FDA found the information provided to be sufficient.


Heme is “responsible for the flavor of blood,” Impossible Foods Chief Executive Patrick Brown said in an interview this year. “It catalyzes reactions in your mouth that generate these very potent odor molecules that smell bloody and metallic.”

What’s at issue is how it looks. An FDA spokesman said heme, which is red, needs to be formally approved as a color additive before individual consumers can buy the uncooked product.

“If the firm wishes to sell the uncooked, red-colored ground beef analogue to consumers, pre-market approval of the soy leghemoglobin as a color additive is required,” FDA spokesman Peter Cassell told Bloomberg in a Dec. 17 email. Impossible Foods filed a petition Nov. 5 seeking heme’s formal approval as a color additive, the FDA said. The agency has 90 days to respond, and the timeline can be extended.

Impossible Foods says heme isn’t a color additive as currently used in cooked Impossible Burgers sold in restaurants. However, other future uses might qualify as a color additive, company spokeswoman Rachel Konrad said in an email. The company submitted the FDA petition to retain “maximum flexibility as our products and business continue to evolve.” Konrad declined to say whether uncooked heme-containing products to be sold in supermarkets were one of those contemplated future uses. “Impossible Foods is in full compliance with all federal food-safety regulations and has been since 2014, well before we launched a product at restaurants in 2016,” she said.

The color additive FDA filing won’t affect the continued sale of cooked Impossible Burgers in restaurants, and FDA approval of the color additive petition could come in time for the company to roll out the raw product next year, as planned.

The demand for it is definitely there. Once just the province of animal welfare advocates and the health conscious, the meat-alternative market has turned white-hot, given the massive role industrial meat production plays in global warming.


Impossible’s biggest competitor, Beyond Meat, is backed by food giant Tyson Foods Inc. Its pea-based, beet juice-colored Beyond Burger already sells in supermarkets and has seen 70% annual growth. The El Segundo company has even filed for an initial public offering. Both Impossible and Beyond count Microsoft Corp. founder Bill Gates as a backer (he helped raise $450 million for Impossible). Other meat giants, such as Minnesota-based Cargill Inc., are investing in the rapidly growing sector, too.

According to Neal Fortin, director of the Institute for Food Laws & Regulations at Michigan State University, Impossible Foods’ color additive petition probably includes evidence of heme’s safety. He said the FDA will evaluate the submission, take public comment and issue a final rule. Although the safety standard for food additives and GRAS substances is the same, there’s arguably more on the line with this evaluation: The FDA will be making a more substantive safety determination than under the GRAS process, and the comment period opens the door to critics. The agency could also ask for more safety tests. (Impossible Foods and the FDA declined to share the petition with Bloomberg.)

“If you slow the process down, and there’s public comment and groups sign in and scientists have to affirmatively say it’s safe, it makes a tremendous difference,” Fortin said.

Heme is a naturally occurring, iron-containing molecule that’s abundant in the blood and muscle of animals. It also exists in smaller amounts in plants such as soybeans — specifically nodules on their roots, which Impossible Foods harvests for use in its burgers. The company has pointed to heme’s natural occurrence in animal flesh as the reason it tastes so much like meat.

But the company has also promoted its Impossible Burger by saying it looks like meat.

Except in certain categories, a company can start selling novel ingredients in the United States as food whenever and wherever it wants, as long as a panel of third-party experts reviews it and deems it safe. If it wants the government’s blessing — a way to win consumer confidence — the company can present its results to the FDA. The regulator can either raise questions or accept the conclusions and issue a “no questions” letter. The safety standard applied by the FDA is, as Cassell stated in his email, “reasonable certainty of no harm under the conditions of the intended use.”

Impossible Foods convened such an expert panel to evaluate heme’s safety in 2014. When it first showed the FDA its evidence, the regulator said the company had yet to prove heme was safe. The company followed up with a 1,000-page filing. It included studies on a variety of topics — including allergens, identifying proteins, and rats made to eat heme for 28 days — all to show that heme should be “generally recognized as safe.” In July 2018, the FDA issued a “no questions” letter in response to Impossible Foods’ GRAS filing.


The agency did offer a caveat, however. “There is no GRAS provision for color additives,” the FDA wrote. “In Impossible Foods’ notice, soy leghemoglobin preparation is described as red/brown. As such, the use of soy leghemoglobin preparation in food products (other than ground beef analogue products intended to be cooked) may constitute a color additive use.”

“Part of the potential consumer appeal of the uncooked product is that it also looks like ground beef,” Cassell, the FDA spokesman, wrote to Bloomberg. “The soy leghemoglobin imparts a red color that is important to the appearance of the food (i.e., makes it look like uncooked ground beef). Therefore, if the firm wishes to sell the uncooked, red-colored ground beef analogue to consumers, pre-market approval of the soy leghemoglobin as a color additive is required.”

Konrad, the company spokeswoman, said the FDA has already fully evaluated and accepted the safety of heme. She declined to say whether the company will delay the rollout of raw Impossible Burgers to consumers until the FDA makes a ruling on its petition. “It’s absurd to suggest that the mere fact that leghemoglobin, an intrinsically safe ingredient, has a visible color should raise any new safety concerns,” she said.

Substances used to color food have long faced stricter federal safety requirements. The higher level of scrutiny stems from a long history of U.S. food and cosmetics companies using dangerous chemicals to color products. The Federal Food, Drug, and Cosmetic Act of 1938 included new regulations around color, specifically those derived from coal tars. In the fall of 1950, a number of American children were sickened by Halloween candy that was discovered to have been made with a toxic orange dye containing benzene. A subsequent FDA investigation showed it was a widely and heavily used substance. In 1960, the law was amended to require more federal oversight and pre-market approval.

“Under the Food, Drug, and Cosmetic Act, a food is adulterated if it has a color that hasn’t been approved,” said William Senior, who is an attorney at Benjamin L. England & Associates in Long Beach and a consultant with A key distinction, however, is when an ingredient imparts a color incidentally, he said. To trigger FDA review, the ingredient’s inclusion must be intended — at least in part — to add color.

“Advertising,” said Tom Neltner, chemical policy director at the Environmental Defense Fund, “is the best way to determine intent.”


In the past, Impossible Foods has cited the current product’s appearance in marketing and other materials. Originally, the company called heme “Rubia,” according to documents it provided the FDA in 2015. The name was used at the time, Konrad said, “because the FDA asks food manufacturers to have a ‘common or usual name’ for ingredients in GRAS notices.”

In a July 2016 announcement, Impossible Foods said its burgers would be available at the New York restaurant Momofuku Nishi. In the release, the company said the burger “looks, cooks, smells, sizzles, and tastes like conventional ground beef.” According to an Aug. 24, 2017, version of the Frequently Asked Questions section of the Impossible Foods website, accessed through the nonprofit internet archive Wayback Machine, “Heme contributes to the characteristic color and taste of meat.”

Photos of the burger, in media and on the company website at that time, also show a red, bloody-looking medium-rare burger.

In a Sept. 5, 2017, letter to a lawyer for Impossible Foods obtained by Bloomberg News, the FDA noted that the company’s draft GRAS notice didn’t include a reference to “the color of the protein preparation or of the effect its color could have on the appearance of the intended food products.” The regulator wrote that “Impossible Foods’ website explains that ‘heme’ also contributes to the characteristic color of meat and shows pictures of red and brown ground beef analogue products.”

Though FDA spokesman Cassell declined to comment on the letter, he said in a Dec. 18 interview that “when we reviewed the GRAS notice, we came to the determination that it wasn’t a color additive under its intended use, meaning in restaurants, and the company came to us to use it as a color additive for the new use, selling it raw in supermarkets.”

Konrad said heme was not added for its appearance. “It would be ridiculous to use heme for color,” she said, adding that there are cheaper and easier options, such as beet juice. “Because the importance of heme stems from its impact on taste and smell, we do not emphasize its color in our marketing materials.”


Senior said that, regardless of questions of intent, the new FDA review is unlikely to keep raw Impossible Burgers out of supermarkets. Although the color additive review process is more stringent than the GRAS one, he said, rejection of heme as a color additive after it’s already gone through GRAS is “very unlikely.”

Food safety advocates say the entire episode is emblematic of larger questions about the burgeoning meat-alternative segment and, more broadly, the FDA approval process itself.

Michael Hansen, a scientist at Consumers Union, the research arm of Consumer Reports, said the heme used in Impossible Burgers should be considered a color additive even in its cooked form and shouldn’t be on the market until it gets approval as such. Some additional, longer-term tests would have given consumers a better picture of the product’s safety, said Lisa Lefferts, a senior scientist at the Center for Science in the Public Interest.

“If people are going to be eating this, it should be tested for its long-term effects,” she said. (Hansen has been critical of other food technologies, especially those involving genetic engineering. Lefferts has disagreed with earlier FDA approvals of sugar substitutes.)

Laura MacCleery, the Center for Science in the Public Interest’s policy director, said — without specifying Impossible Foods — that companies with innovative products shouldn’t be looking for shortcuts with safety if they want to build trust with consumers.

“It’s incredibly counterproductive and shortsighted to think it’s not a good investment in consumer confidence to take all of the steps on safety seriously,” she said.


Konrad rejected any notion that Impossible Foods cut corners, saying the company “has never and will never try to avoid any food safety tests or requirements.”

As for the FDA process itself, advocates have long agitated against rules that allow products to be sold without having first obtained government approval. A group of consumer, health and food safety groups sued the FDA last year in federal court in Manhattan, calling the GRAS system a “loophole” for companies to skirt pre-market government safety reviews and secretly add chemicals to food.

While the GRAS laws originally applied to well-known ingredients widely known to be safe, the groups argued, the FDA has been applying it to innovative ingredients that are new to the human diet.

The regulator rejected the lawsuit’s allegations and challenged the standing of the plaintiffs to sue. But in September, a federal judge ruled that the plaintiffs could challenge the GRAS rule, allowing the case to move forward.