How the roots of the legume plant may give us the answer for a better food future? Why is everyone talking about Impossible Burgers and Heme, the ingredient behind meat-free bleeding burgers? What is Heme and why is it such a juicy topic?
We live in a time when food technology needs to evolve rapidly and we need to find ways of eating, which would not destroy our planet. Born out of this necessity is the Silicon Valley start-up Impossible Foods. Founded by Mr Pat Brown, a biochemist from Stanford University, this food venture has indeed taken a great step in combining genetics, microbiology and cutting-edge chemistry to come up with a solution and that is making a meat-free burger that tastes juicy & can bleed like a perfectly cooked medium rare burger oozing with juicy cooking liquids.
Using the soy leghemoglobin protein, a protein which is naturally found within the root nodules of Soy legume plants, scientists found a way to produce livestock free meaty tasty legume burgers. They argue that our neurochemical craving for meat is actually craving for the taste of iron and protein-rich Heme. That means, as the iron and protein of a burger patty can easily come from the plant-based source and if they are combined with heme we can make the perfect bleeding burger that bleeds itself but does not make the planet bleed due to problems associated with mass-produced livestock.
How Heme makes the veggie burger tests meaty?
In a traditional burger, flavour and aroma of meat burger results from Maillard reaction & the presence of heme in the meat tissue. During cooking when the heat is applied, alongside the browning of meat by maillard reaction, myoglobin in beef releases its heme and therefore a medium rare burger patty bleeds.
Similarly, in a soy leghemoglobin infused burger heme is also released during cooking and given the Iron-rich nature of heme, a very meat-like test and texture results with oozing juices.
Let us get to the root of Heme!
Millions of years ago as the evolutionary jump took place and plants belonging to the Fabaceae or Leguminosae family broke away from their flowering-plant ancestors by acquiring genetic traits that made them unique ( and meatier) & gave rise to pulses.
As these plants flourished across the globe, across diverse ecosystems and climates, over time plants such as Leguminosae developed specialised structure and pocket within their roots which are known as nodules. It provides something like a housing facility for the bacterial genera Rhizobium and Bradyrhizobium to grow inside in an enlarged form known as bacteroids which operates more like plants’ own nitrogen factory.
Just like any thriving manufacturing line today, these nitrogen factories need a close monitor and constant regulation of supplies. Especially the oxygen concentration is vital because oxygen inhibits nitrogenase and too much or too little of oxygen can both be drastic. The plants therefore employ symbiotic guardians named leghemoglobin, which is an oxygen-binding protein similar to haemoglobin in our blood.
Leghemoglobin in Legume plants are formed of Globins, one of a group of globe-shaped proteins found in both animals and plants and wrapped up in the amino acid chain of the Globin resides Heme, the oxygen regulator which comes from not the plant itself but the bacterium and works in a symbiotic relationship. Together they help maintain the legume plants nitrogen factory.
Alongside proving a meaty taste to your vegan burgers this nitrogen fixation capability makes the legume plant a true champion of food sustainability and responsible farming.
However, extracting the heme directly from the roots of legume plants might not be the most cost-effective way to go about it because the leftover roots of legume plants after harvest are fundamentally important. for nourishing the soil and making it ready for replantation. For scaling up, Mr Pat Brown’s team did not have to look too far to find a scalable method. Apparently, yeast, our favourite sugar fungus that more or less shaped our human civilization once again came to the rescue. Yeast has been well known by us for centuries and probably one of the most commonly consumed product.
Taking the DNA from Legume Plant roots and inserting it inside the yeast cells—specifically Pichia Pastoris, one of very commonly used yeast in biotech Mr Pat Brown’s team have brewed up the modified yeast, much the way you’d brew beer.
However in this brew rather than yeast releasing alcohol it releases globin which is then filtered out of the yeast and other byproducts until the leghemoglobin is about 80-percent pure. Subsequently running various tests in molecular-level analyses they have made sure that concerns on food allergies are properly looked at and after a comprehensive literature search and they found that not only was leghemoglobin not associated with allergies, but the whole plant-based globin class was free from allergy reports.
Besides after a through reviews, FDA has also approved the use of lab-cultured soy leghemoglobin by Mr Pat Brown and his team. Hopefully, the initial concerns that were raised regarding the issue of food safety with cell cultured Heme used in scale up production have been dealt with fair and square.
A great initiative indeed. Saving the planet, one burger at a time!
What do you think?