Three Masters of Science graduates were overheard talking about the impossible burger— if you haven’t heard about it, it is a vegan-meat substitute produced by Impossible Foods Inc. which palatably mimics an actual ground-beef burger. The one was telling the others, that the burger was not only delicious and filing, but that it smelled and tasted like real beef. When questioned as to what gave it the beef-like sensation, she answered heme, but was unsure of the source of the heme. This was puzzling because most people are familiar with heme being a component of animal blood, and the idea that heme could be vegan or synthetically produced from amino acids in a lab seemed dubious. 

However, as it turns out, heme is ubiquitous to many living organisms, and can be found in  bacteria, fungi, protozoa, higher plants, and animals. In fact, the heme used by Impossible Foods Inc. is derived from a plant heme known as leghemoglobin, that is sourced from soybeans. The leghemoglobin is not directly extracted from the soybean, as extracting leghemoglobin from plant roots is tedious and not cost effective due to low yield. Therefore, to increase productivity, the leghemoglobin is synthesized through genetic engineering. Continue reading →