Biotech basics in the battle for beef's bloodiness - Part II

v2food's take on the Impossible

• 30 June, 2022

This post summarises some biotech concepts and industry movements I’ve learned as a newcomer to the field. It’s intended to be narrative, notes and references that past-me would have found interesting and useful.

It follows on from Part I where we looked into precision fermentation as a means to produce heme proteins - a high value ingredients that give meat its “blood” characteristics. We also touched on the legal battle between heme producers - Impossible Foods with their wide-reaching patent and Motif challenging the patent’s validity.

Food in space

Precision fermentation brings to mind the science fiction trope of growing food in giant vats for the first non-Earth colonists. But though yeast grows quickly¹, it requires an organic carbon feedstock. This is true of most microorganisms, but in the resource constrained environment of space, we need to go further down the food chain.

An organism that doesn’t require an external source of organic carbon for food is called an autotroph. Autotrophs create food² for themselves (or others) from simple substances. Many bacteria are autotrophs, as are plants. But plants are bulky for the human-food yield they produce, and bacteria are kind of risky. Algae³ sit in a kind of sweet spot - fast growing, high food-yield autotrophs.

Since the 1980s algae has been a food source of interest for life support eco systems such as those we might build in early space settlement. This NASA study from 1988 on the Arthrospira (nee Spirulina) species showed a fast growth rate and high biomass yield, with nutrient mix able to be varied by environmental conditions during cultivation. Studies continue into nutrition mix of algae cultivated in harsh environments. Note the different application - rather than producing a specific target, this is the large scale production of nutritious biomass to sustain human life.

Who’s your favourite autotroph?

As in plants, algae’s autotrophic capability comes from its chloroplast - the engine room that performs photosynthesis. Photosynthesis uses the energy of light⁴ and the raw material of carbon dioxide to create starches and simple lipids⁵. The algae’s mitochondria uses these to perform cellular respiration, power the rest of the organism, and often produce a target molecule⁶, if that’s what you’re going for.

Though we may not recognise it, algae are quite central to our existence. It’s generally understood that algae photosynthesis is responsible for about half of the earth’s oxygen, or three-quarters of the oxygen needed for all humans and animals. As they’re at the base of earth’s biological food chain, we rely on it not only to be our food’s food, but to generate key nutrients we need to thrive. Most notably, long chain fatty acids such as Omega-3s that we appreciate in fish was all created by algae that the fish ate. And it’s not just today’s algae, but the algae that grew millions of years ago we believe to be the source of the majority of crude oil.

As an organism that has the benefit of aeons of evolution, algae is quite prolific. There’s estimated to be somewhere between 30,000 and 5,000,000 species of “algae”, a fraction of which have been characterised, and only a handful of which are grown commercially. There is still tremendous opportunity in exploiting what algae can already provide. Further, as rapid reproducers (an algal organism can divide by mitosis within 24 hours), they are quite well suited to selective breeding in order to optimise performance. There’s the option to use genetic modification, as is done with other microorganisms, but today the genetic-expression-phenomenon (pardon the phrase) space seems to be less well explored⁷.

So it can be worth looking at algae for your high value food ingredients, such as our heme proteins. To find your starting strain you need to go prospecting. It’s not all All Gold Canyon though, there are large data banks available with thousands of species profiled, or at least catalogued. If you find something you like in a data bank, then you have a lead for where to find it in nature.

Enter v2food

v2food was founded on a big ambition: rather than stop people craving the meat they are genetically and culturally wired for, offer a sustainable meat. Not some new strange thing; the family favourite spag bog, schnitzel or kofta can not be threatened. Create a plant-meat that looks, cooks and tastes just the same as an animal-meat. Oh, and make it cheaper.

The current iterations of v2food’s meats are pretty impressive, but they lack our theme: heme. And they can’t - as we know heme is tied up by Impossible Foods.

But v2food have an ace up their sleeve. Recall that hemes are a type of macrocyle tetrapyrolles - that is four pyrolles arranged in a circular shape. It turns out four pyrolles can be combined linearly, in an arrangement called a bilin. There is a bilin derivative called phycoerythrin (a phycobiliprotein⁸), and v2food have found an algae that produces a phycoerythrin they claim to be useful as a colouring agent⁹ in meat-mimetic foods.

We can glean some of the detail from their patent. In it they describe a phycoerythrin that both has the desirable red colour, and also denatures (losing its red) at cooking temperatures. Not only a colouring agent, the patent describes art for chelating iron with the phycoerythrin. They have a protein that has the key characteristics of heme, without actually being a heme and therefore not covered by Impossible’s patent¹⁰.

How good is it really? The patent goes on to describe experiments that v2food have performed. It seems the colour hue and depth can be varied by applying ultrasonic energy to (aka sonicating) the algae sample - allowing for variations from the default fluorescent pink to blood red. Burgers with the ingredient start off being blood red and when cooked change colour and produce a pooling of red liquid. The chelated iron promotes (model) in vitro production of ferritin. And, in a neat patent-as-marketing move, a comparison against burgers with haemoglobin and myglobin added it was shown that only the phycoerythrin burger had an improved umami flavour.

There’s more in the patent, it’s quite a good read.

So where is my algae?

Finding an algae that creates your desired ingredient is only half the battle; you still need to produce it at scale. The lessons of the failed biofuel revolution shouldn’t go unheeded - algae can grow really well, but biomass density is a challenge¹¹. And the need for a light source means the efficiency of a large vat is probably not available to you. It’s a theme that in the world of atoms scaling is almost always the bottleneck.

v2food CEO Nick Hazell talking about their algae-heme describes a plant that looks a bit like a dialysis machine so it seems that scaling up production is under way. This could be just the improvement needed over the traditional ponds and lakes.

Watch this space

This has been a fascinating dive into a small corner of the biotech industry. I hadn’t thought that the satisfying red juicy experience of cooking meat could be grown by yeast or occur naturally in algae! It’s hard to predict where we’ll be in a few short years, but the future of food is looking rosy.