Soy leghemoglobin is short for legume hemoglobin -- the hemoglobin found in soy, a legume. Hemoglobin is a protein found in plants that carries heme, an iron-containing molecule that is essential for life in every living being -- both plants and animals. (Heme in animals is carried by “myoglobin.”)
Although heme has been consumed every day for hundreds of thousands of years, Impossible Foods discovered that it’s what makes meat taste like meat. We make the Impossible Burger using heme from soy plants -- identical to the heme from animals -- which is what gives it its uniquely meaty flavor.