Cellular Agriculture — Who, How, and When
Imagine if your prime product, after years of development and experimentation, cost an astounding 8,000,000% more than the product it wants to replace. Impressively, the burger patty no longer costs such a sum (although not for sale, it costs £9), and even more impressive is how Mosa Meats developed the first cultured burger patty.
Mosa Meats, started in 2016, is a company developing cell-based meat. Determined to tackle the issues of food production, the increasing global population, and the issue of Climate Change Mosa Meats has been engineering their cell-based approach to meat to replace ordinary beef.
The issue:
The current process of getting beef leads to environmental inefficiency and pollution, in addition to the animal cruelty.
Emissions —
Meat, especially beef, are a grand contributor to emissions (and if you didn’t know, emissions are the cause of this super annoying problem called climate change).
Beef comes from cows. You may have heard how “cow burps” or “cow farts” release a lot of emissions, and in some part this is true. Each cow will belch or flatus 220 pounds of methane, a gas 28 times stronger than C02! In fact, cattle are the #1 agricultural source of greenhouse gases. The meat and dairy industry produce 7.1 gigatons of GHGs (greenhouse gases), with each kilogram of beef produced emitting 60 kilograms of GHGs.
Aside from direct emissions, cattle also produce a range of environmental inefficencies. The growing demand of beef leads to farmers cutting down forests and trees (the same things that absorb CO2). Such destruction of rainforests caused 40% of the Amazon rainforest to be in danger of deforestation.
Beef and cattle are also huge wasters of water. Through the amount of feed they go through and their natural intake of water, it takes a whopping 1,910 gallons to obtain 1 pound of beef.
Efficiency —
While beef production produces a considerable amount of emissions today, the predicted future for beef demand (and thereby emissions) isn’t so comfortable. Just within Asia, there’s a predicted 300% increase in beef demand in the next 30 years. The expected beef, lamb, and goat global demand is predicted to rise 88% (2010 -> 2050). As more and more countries become richer and richer, the demand for beef and other meats also increase.
So, how do we solve the problems of food-demand and emissions as the population grows?
Cellular agriculture.
The solution: Cellular Agriculture
Mosa Meat’s direct solution to this issue is their cultured meat burger, a slab of beef created in a lab. At the moment, Mosa Meats are still trying to reduce their burger price to around $11 a burger to enter the market; yet, they’ve made so much progress from their quarter million dollar burger a few years back. To understand where companies like Mosa Meat came from, and where they’re going, we’ll need an overview of cellular agriculture.
Cellular Agriculture is REALLY complicated.
The process of CellAg differs throughout the types of meats and what type of product someone wants to grow. In our case, we’ll take a general overview on how someone would make “conventional meat” :
- Muscle Sampling
- Isolation of Muscle Stem Cells (MSC)
- Primary Culture of Muscle Stem Cells (MSC)
- Bioreactors: Cell Growth Chambers
- Harvest and Processing of Muscle Tissues
Source: CellAg @ MIT
1. Muscle Sampling —
The very first step of CellAg is to get a muscle stem cell sample. To do this, cellular agriculture companies will go through a process called a muscle biopsy, where someone will extract muscle stem cells from a cow.
Why Muscle Stem Cells: In order to produce a cluster of muscle cells large enough to be cooked with and consumed, scientists must start with a cell with a larger ability to replicate itself. Most cells become senescent, or stop dividing at a certain amount of time. Muscle stem cells have the ability to keep dividing/replicating itself for a much longer, and the ability to differentiate itself into different types of cells. MSC’s are also known as satellite cells.
The first step to conducting a muscle biopsy is identifying the right cow to extra cells from. Factors such as age, sex, species, location of muscles, and more will be identified in order to conduct a biopsy.
The actual extraction of the muscle is conducted by inserting a needle into the correct area and extracting a few cells.
2. Isolating MSC’s —
After the clump of muscle cells is extracted from the animal, the muscle stem cells must be extracted from the clump. When a biopsy is performed, a clump of cells from muscle tissue is extracted. This clump of cells includes muscle fibers, connective tissues, stromal cells, and satellite cells; the next job is to isolate the satellite cells.
In order to do this, a scientist will use scissor or a meat mincer to physically separate the MSCs, use enzymes to disassociate the cells, filter with the use of a centrifuge, and other techniques such as fluorescence-activated cell Storting, magnetic-activated cell sorting, and other such processes.
Enzymes: The use of proteases, an enzyme that breaks down proteins, including trypsin, pronate, collagenase, and dispase are used for purifying the cells after any physical changes to the sample. Varying combinations of enzymes can be used depending on the condition of the sample. If a large part of the muscle sample has been purified, other enzymes may be used to target connective tissues, fiber garments, and tissue debris.
Some fun terminology common in cellular agriculture:
In vivo means “within the living” whereas in vitro means “within the glass”
3. Primary Culture of Muscle Stem Cells (MSC)
Now that we have our muscle stem cells, it’s time to start growing!
In order to do this, scientists will use something called a cell culture media. This solution is full of nutrients which will grow and feed our newly isolated satellite cells. Cell culture media (CCM) will also help maintain pH, help with proliferation and differentiation, and other processes of growing cells.
Cell culture media (CCM) is also where most of the cost of a CellAg burger comes from. Around 55–95% of the cost of meat production costs will come from the media. This is also why decreasing this cost is one of the biggest issues, as the faster we decrease this cost the faster cellular agriculture meat will by financially logical for mass distribution.
Most CCM is composed of vitamins, water, salts, amino acids, a carbon-based energy source, and other parts to produce a basal media. Each of these ingredient have a specific role:
- Carbon-based energy source — Cell Energy Source
- Amino acids — Used to create Proteins
- Salts — Helps to maintain osmolarity
- Vitamins — Cell growth, cofactor, etc.
SERUM —
A serum is used with this media and cells in order to promote growth and health of the cell cultures. 5–20% of the serum will be added to the basal media. Typically, serum will contain everything blood contains minus the clotting components. This means a serum will have:
- Electrolytes
- Antibodies
- Antigens
- Hormones
- Lipids
Fetal Bovine Serum (FBS) is obtained by extracting blood from a mature fetus, and is typically a byproduct through whatever meat processing occurs. Fetal blood is coagulated, centrifuged, and then harvested for its serum. FBS is the main serum used, but many are trying to phase it out due to ethical and logical concerns.
FBS is also very, very expensive. The price can cost around $1000 per liter, and the overall volatility of the price is extremely aggressive. FBS is very much not a sustainable solutions for the future.
4. Bioreactors: Cell Growth Chamber
Bioreactors are automated and controlled chambers that will allow and enhance the growth of cells. There are various types of chambers, including single use and stainless steel chambers. The typical style used by these companies are stainless steel chambers.
Typical flat culture dishes do not have a high enough surface-to-volume ratio for cell-growth. They’re also to difficult to control pH levels and metabolic concentrations. Bioreactors solve these issues, in addition to providing more space time and resources, allowing for mass culture and high-density cell cultures.
The bioreactor cultures “microcarrier-attached” ells by optimizing the conditions, such as pH, temperature, gas, nutirion concentrations, and more.
5. Harvest — Downstream Processing
After our cells have grown accordingly with the scaffold, we can now start downstream processing to harvest our grown meat.
Edible Scaffolding- If our scaffolding is edible, and will be part of the final piece of meat, we’ll start with washing our media and sells, and then initiating flocculation which helps us drain the media and separate it from the cells.
Inedible Scaffolding- In order to separate the cells from the scaffolding we can use TrypLE, an enzyme mixture. After using the enzyme, we can just centrifuge the cells and filter the mixture, and then press together our harvest.
After both of these processes, we tissue press the cells together and bam, cellular agriculture meat!
Current Companies in the CellAg Space
In all growing spaces, there are always innovative companies pushing the boundaries of what’s possible. Here are a strong few….
Mosa Meats — — —
Mosa Meats, the same company which inspired this article, started in 2015 with the first ever cultured meat burger. Their burger emits 96% less emissions than typical beef. Mosa Meats, on track to start manufacturing cultured meat burgers in the coming years, creates their meat through he process we just described — taking muscle biopsies and cultivating them into large structures of meat.
Formo — — —
Formo, started in 2018 in Germany, creates European cheese created from cells. Formo creates their cheeses through synthetic biology paired with the typical manufacturing styles of dairy to create these products. Formo’s cheeses act, taste, and cook just like typical cheese, but are also vegan and lactose-free. Formo avoid 9 tons of GHG emissions per ton of produced cheese.
Higher Steaks — — —
Higher Steaks, founded in 2018, produces bacon and pork belly created from cultured cells. Higher Steaks uses a unique process of using iPSCs, or induced pluripotent stem cells that they convert into blood samples for muscle, fat, and skin tissues.
This process of creating cellular agriculture meat varies so, so much from company, product, organization etc. What’s more a question, is how each of these parts of the process will change and evolve, especially as science advances, and the quest to feed our growing population expands…
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