Impossible Burger's 'secret sauce' highlights challenges of food tech

New York

ONE of the chief selling points of the Impossible Burger, a much ballyhooed plant-based burger patty, is its resemblance to meat, right down to the taste and beeflike "blood." Those qualities, from an ingredient produced by a genetically engineered yeast, have made the burger a darling among high-end restaurants like Momofuku Nishi in New York and Jardinière in San Francisco, and have attracted more than US$250 million in investment for the company behind it, Impossible Foods.

Now, its secret sauce - soy leghemoglobin, a substance found in nature in the roots of soybean plants that the company makes in its laboratory - has raised regulatory questions.