How To Save the World Without Going Vegan
Cellular agriculture can reduce climate change without compromising our diets.
Dear fellow meat-eaters,
Meat tastes good. Believe me, I understand how hard it is to give up your consumption of Thanksgiving turkeys, steaks, burgers, chicken nuggets, salmon filets, pork chops, ribs, cheese, and eggs.
I too have trouble cutting out these foods because I love eating them and it’s almost impossible to avoid them. They’re in smoothies, cookies, ice cream, bread, and even salad dressing 🤯
However, the way we make food is extremely ineffective. 69% of the world’s fresh water is being used for agriculture: it takes more than 2,400 gallons of water to produce 1 pound of beef. That’s 10 years worth of drinking water!
Cows are only 3% effective at converting nutrients and water into meat.
Why are we spending time, wasting land, and investing over 1.1 trillion dollars into a 3% efficient machine? That just does not make sense!
In the world, 1 in 7 people do not have access to clean water and 1 in 9 people do not have an adequate food source. In the time that you spend reading this article, 200 people will have died from hunger. This has been happening for years, yet minimal progress has been made.
Why hasn’t anything been done to solve this? We hear about people adopting the vegan diet and reducing food waste all the time, but only 0.1% of the world’s population has successfully maintained the vegan lifestyle. If we want to reduce the effects of climate change, we need to get the rest of the world on board and fast.
What’s worse: with the world population rising to a shocking 10 billion people by 2050, there will be 7.3 billion meat-eaters that we need to feed. We need a new solution.
How can we increase the efficiency of meat production, reduce greenhouse gas emissions, and get meat without killing animals?
The answer is cellular agriculture: the production of meat products from cell cultures (or in-vitro techniques). It uses tissue engineering and biotechnology to create products that would otherwise come from traditional agriculture — essentially making beef without the cow and getting eggs without the chicken.
How it Works
There are two kinds of cellular agriculture:
- Cellular products. These are usually the products that come to mind when you think of an animal (meat, leather, and fur). Cellular products are made of living or once-living cells.
- Acellular products. AKA your milk and eggs. Acellular products are made of organic molecules like proteins and fats and contain no cellular or living material. (I’ll be releasing another article explaining this more in depth so stay tuned!).
How to Make Cellular Products
To make cellular products, we need to make tissues. Our bodies are made of tissues which are a bunch of different cells strung together.
In cellular agriculture, we do this by using a process called tissue engineering. Tissue engineering is similar to taking care of a plant. We take tissue and stem cells from an animal and give them something to grow on (a scaffold).
Then we give them some of the nutrients that they need and a serum that nourishes the cells with the right ratio of sugars, fats, proteins, and vitamins.
Once the stem cells start growing into little beads of meat (myoblasts) in our cell flasks, they are transferred to a bioreactor (a machine that provides the cells with the necessary environmental triggers such as temperature and exercise) which helps the cell proliferate and reproduce. Our little stem cell babies will then grow and give us meat.
Throughout this process, the animal is not harmed and we can theoretically get meat forever from just a couple of stem cells that keep replicating. It’s a win-win situation!
Fun fact: tissue engineering is actually used in medical applications such as growing skin for burn victims, or organs for patients requiring organ transplantation where the new body part is grown from the patients own stem cells! Learn about this here.
In the case of growing meat, we focus on promoting nutritional value, mouthfeel, and taste, instead of prioritizing functionality like you would if you were making an organ for someone’s body. All cellular agriculture products need to be made affordably — which means producing tissues at a scale much larger than what is required for patients requiring organ transplants.
Getting the Stem Cells
A stem cell is an unspecialized cell that has a unique ability to self-renew or differentiate (change) into another cell type.
Stem cells are the seeds that our meat “plant” grows from. They are the starting point for growing in-vitro meat and determine the texture and feel of our final product.
Stem cells are taken from an animal through a biopsy (sample of tissue taken from the body harmlessly). The location of the original muscle biopsy determines the taste of the meat. The skeletal muscle of different body areas has different certain gene expression patterns and fiber-type composition.
There are many types of stem cells, defined by their potency or ability to differentiate into other cell types. They will have different usages in growing cultivated meat.
Totipotent stem cells: A totipotent stem cell is a stem cell that can differentiate into any cell type of the body. Totipotent stem cells only exist roughly up until the 8 or 16 cell stage of development.
Embryonic stem cells: Embryonic stem cells are cells that can differentiate into cells of all 3 germ layers (ectoderm, mesoderm, and endoderm) but they can only be taken from the placenta during the development of an embryo. Bovine embryonic stem cells (ESC) can differentiate into all cell types required to recapitulate the muscle development required for meat.
Induced pluripotent stem cells: A technique developed by Yakanova showed that adult stem cells can have similar characteristics if they are wiped of their epigenome and become induced pluripotent stem cells (iPSCs). These adult cells are activated by viruses to turn on 4 key genes which make them go back to being pluripotent instead of multipotent.
Multipotent stem cells: Multipotent stem cells can differentiate into a limited number of cell types, but not always within a single germ layer.
To accurately replicate meat, we need to consider the composition of muscle, fat, and blood cells. Meat contains about 90% muscle fibers, 10% connective and fat tissues and 0.3% blood. The muscle fibers can be created in-vitro using stem cells, but in order for the final product to actually taste like meat, fat tissues and blood tissues also need to be added from the serum.
Cultured meat commonly starts from purified myosatellite cells (also known as muscle stem cells or satellite cells). They are small multipotent stem cells that can be differentiated into muscle tissue (aka meat) through proliferation.
The process of creating muscle tissue through myogenesis:
To prepare the satellite cells:
- We use a gene regulation shift (downregulation of PAX7 and up-regulation of MYF5 and MYOD) to activate satellite cells so that they turn into myoblasts (embryonic cells that differentiate to form our muscle tissue)
- We put the myoblasts around a gelatin ring that promotes muscle fusion, contraction, and growth. Using this method, individual myotube rings can be harvested and compacted together forming a shape similar to ground meat.
What do we feed the cells so that they can do this?
Feeding Cells the Magic Potion (Serum)
The three steps that stem cells need to go through are proliferation, differentiation, and maturation. Since we don’t have the normal blood supply providing nutrients and removing waste to and from our stem cells, they need to be bathed in a culture media which provides the important nutrients and growth factors.
The required nutrients (carbohydrates, lipids, amino acids, and vitamins) are fairly easy to calculate and add to the cells. However, different growth factors and hormones are also needed to encourage the cells to continue growing and proliferating. These growth factors are usually provided by adding 10% to 20% growth media.
Without adding serums to our petri dish, our satellite cells encounter something called cellular senescence, where they stop dividing after a certain number of divisions is reached (Hayflick Limit).
This is because the chromosomes that make up the DNA of the cell have these little caps at the end of them, called telomeres. They protect the ends of your chromosomes, but over time, they shorten until your cells become senescent (stop dividing).
In order for the stem cells to grow into myoblasts, they need to be given the right juices to continue dividing and growing. Here’s where the growth medium comes into play.
The most popular growth medium is a fetal bovine serum (FBS). It is a growth media created by drawing blood from a fetus inside of a mother’s bovine (cow). FBS stops cell deaths because it contains growth factors (substances that can lie to cells and convince them to keep living).
One huge advantage of using FBS is that it is universal for every cell type. You can toss any type of cell into a petri dish with FBS and it will grow, whereas other growth mediums don’t have that universality. Most alternatives are cell-specific, so if you want to grow muscle tissue, you have to use a muscle tissue serum, and if you want to grow brain tissue, you must use a different brain tissue serum.
Unfortunately, FBS is extremely expensive and it costs around $1100 just for one 500mL bottle ($220/100 mL) of growth medium 👆.
Additionally, there are ethical issues with using blood from a fetus because the fetus remains alive when a needle is inserted into its heart and its blood is then drained until the fetus dies which takes about five minutes. This blood is then refined, and the resulting extract is FBS. Obviously, this process is not ideal and very disturbing.
Alternatives to FBS:
There are a couple of plant-based alternatives to FBS, but they are considerably more expensive (almost quadruple the price of FBS). Certain companies like BioXcell and Minitube are working on developing plant-based alternatives that are able to scale well and be more economically feasible.
Current prices of alternatives:
- Ultroser G: $950/100 mL
- Soybean lecithin extract: $640/100 mL
No matter the type of growth medium used, the stem cells will proliferate and grow into small tissues with the help of a scaffold and bioreactor👇
Scaffolds — Building the Structure of Meat
Scaffolds recapitulate the different layers of the skeletal muscle connective tissue and give it the structure it needs to grow into something resembling meat texture. They are the framework for our cultured meat and act as the glue that holds the stem cells together in a certain shape.
Without scaffolds, we would just get meat mush. In order to promote tissue development, stem cells need to be co-cultured inside a 3D scaffold that mimics their natural environment.
In vivo (aka when the cells are in the cow), stem cells attach to the network of extracellular matrix (ECM) proteins through receptors located in the muscle fibers. The extracellular matrix is a 3-dimensional mesh of glycoproteins, collagen, and enzymes that transmits signals dictating how the cells should arrange themselves.
This needs to be replicated in our petri dish so that our cells are arranged in a way that we would naturally see them (like in a structured steak for example). When choosing the scaffold, the following conditions should be considered:
- 🔎 Porosity — the number of pores/openings in the scaffold diffuse gas and nutrients to the innermost layers of cells which mitigates cell death from lack of contact with the growth medium
- 💎 Crystallinity — determines the rigidness of the final shape, promotes thermal stability, and water retention in the cells
- 🍃 Vascularization — vascular tissue found in plants can be used to help to transport fluids to the cells. It can help with cell alignment and facilitate gas and nutrient exchange.
- 🧪️ Biochemical properties — determines the cell adhesion through chemical bonding. The necessary chemical cues must be produced to encourage cell differentiation.
- 🍔 Edibility — scaffolds that are not removed from the muscle tissue must be edible to ensure consumer safety
Chitin and Chitosan
Chitin is found in the exoskeletons of crustaceans and fungi. Because of its antibacterial properties, it can be used as a scaffold that neutralizes harmful compounds without using antibiotics.
Chitosan is derived from chitin in a process known as alkaline deacetylation (substituting out certain amino acid groups). Once removed, it can be combined with other polymers to have bioactive properties.
Decellularized Plant Tissue
The cellulose found in the exoskeleton of plant leaves is the most abundant polymer in nature. It is very low-cost and is biocompatible (compatible with living tissue).
To isolate the extracellular matrix of the plant tissue (aka decellularization), SDS surfactant covers the tissue and creates pores. These pores then release the plant’s cellular components making it decellularized.
The plant tissue’s mechanical properties can then be altered so that it resembles skeletal muscle tissue through cross-linking (forming covalent bonds between individual polymer chains to hold them together). The decellularized plant tissue is then covered in other functional proteins which function as the mammalian biochemical cues that the plant lacks.
As a scaffold, decellularized plant tissue helps replicate the natural physiological state of the myoblasts which promotes cell alignment. It can help contribute to the chewiness and juiciness of meat without having to use expensive processes like 3D printing, soft lithography, and photolithography.
Collagen
Collagen is a protein that makes up the structure of connective tissue and is typically taken from cows, pigs, and mice. However, we can also use transgenic organisms that are capable of producing the amino acids needed to produce collagen.
Collagen type I can be produced into porous hydrogels, composites, and substrates which are all effective scaffolds because of their ability to provide the necessary topographical cues and biochemical properties. Synthetic collagen can also be produced through recombinant protein production and works relatively as a scaffold.
Bioreactors
Bioreactors create the perfect conditions for our stem cells to grow. They are kind of like an incubator for chicks (the ones that you raised in your kindergarden class) and just make sure that your stem cells can multiply properly.
They control the growing environment through:
- 🌡 Temperature. How warm the environment is measured in degrees Celsius (in physics terms: the average amount of kinetic energy in each atom)
- 🍋 pH. The number of H+ atoms in the substance. Essentially, the acidity or alkalinity (basicity) of a given material.
- 🔆 Energy. We need to reduce interference from other elements of cells during the culture process.
- 😤 Pressure. The force pushing down on our baby cells. We need the right amount of pressure to promote growth.
- 🥵️ Humidity. The fluidity of water and moisture in the environment also affects the rate at which our cells grow.
In order to maintain the optimal environment, the bioreactor has
- a filtration system
- sensors
- system monitor (contains additional sensors to ensure the best environment)
- thermal technology
- air tube
- a feeding pump (used to put the medium in)
- an aerator to maintain the humidity, keep the liquid ratio, and adjust the oxygen exposure
Bioreactors come in different sizes. They can be industrial and big:
Or small enough to fit on your counter-top:
Overall, bioreactors just provide the best environment for the growth medium to proliferate and dispose of the waste biproducts.
The Beauty of Cellular Agriculture
Why Cellular Agriculture ROCKS and can save the world 🌎
Animal Welfare 🐣: Factory farming causes suffering to more than 75 billion land animals, 10 billion of farmed fish, and up to 2.3 trillion wild fish, all of which subject to immense emotional and physical pain.
Cellular agriculture reduces animal use and slaughter, improving general animal welfare. Because there is no need to kill animals for meat and no need for animals eggs and dairy (will explain this process in my next article), cellular agriculture could spare tens of billions of animals every year.
Mosa Meat estimates that a single cell sample can yield up to 10,000 kg of cultured meat. This translates to only 150 cows to satisfy the world’s total demand for meat.
Environment 🌱: The livestock sector is responsible for 14.5% of GHG emissions, uses 8% of the global freshwater, and taps 30% of Earth’s terrain. With an expected doubling of the global demand for meat by 2050, traditional meat production systems are not going to be sustainable.
Luckily, cellular agriculture requires:
91% less GHG emissions. GHG emissions goes from 14.5% to 1.16%.
98% less water. Water usage goes from 8% to 0.16%.
99% less land. Land usage goes from 30% to 0.3%.
Eliminating Foodborne Illnesses 🍗: Right now, traditional agriculture is extremely strained because of the increasing global population. Two common practices, factory farming and poor animal welfare conditions, cause foodborne illnesses such as swine and avian influenza, and contribute to spreading of E.coli, salmonella, and campylobacter.
Due to these illnesses, 70–80% of the antibiotics used in the United States are given to farm animals and overuse of antibiotics induces selection of antimicrobial resistant (AMR) strains in humans. With current methods, it is estimated that by 2050, AMR will be responsible for more deaths than cancer.
Since cellular agriculture is produced in a controlled and sterile environment, these problems could be avoided and the need for antibiotics could be eliminated.
More Nutrition 🍎: Scientists can actually engineer certain aspects of our food to make it more nutritious for the human body! We have already been able to make meat with fewer saturated fats and more unsaturated fats, make milk without lactose, and eggs without cholesterol.
Potential Drawbacks
The things that are currently keeping cultured meat off your plate 😢
Replication limits: Cells are constrained in their capacity to replicate indefinitely due to telomere shortening — a phenomenon known as the Hayflick Limit. Thus, a population of purified satellite cells is can only replicate around a maximum of 40 times in vitro. In order to get around this, we must use cell culture media and serums which cause issues in themselves.
Cell Culture Media: Most effective media used for cultured meat is still based on animal serum (FBS) and there are ethical issues with using these serums. Companies must move to either a plant-based or chemically-produced medium that can still achieve high cell densities and repeatable results.
Scaffolding: It is fairly easy to grow cells in a monolayer (one thin layer of cells), but more difficult to grow cells in a way that actually feels like muscle and animal tissues. Scientists still need to experiment with different scaffolding materials to see which ones produce products most similar to structured tissues like steak (they are much more difficult to make than something like a burger patty).
Bioreactors: Growing a range of different cell types often requires highly specific and customized food fermenters or bioreactors. It is necessary for companies to have bioreactors that will allow them to develop their processes and effectively scale up for production and manufacturing.
Consumer Acceptance: There is consumer resistance to products grown in a lab (in vitro) and a stigma that cultured meat won’t taste as good. We need to convince more people of the benefits of cultured meat! (You can help by sharing this article 😉). However, studies show that consumers will choose more sustainable products if they are of similar price and quality to traditionally farmed products, meaning that once texture and price improves, cultured meat will be seen everywhere!
Cost: Cultured meat is over three times more expensive than normal beef. The first cultured meat burger was $35,000, which is unscalable in the majority of average consumers. If lab-grown meat were to make an emergence in the consumer market, production methods and material costs needs to decrease drastically.
Cell Line Selection: Companies must optimize their cell line selection (the cells that they choose to start with) so that they are genetically stability, and provide wonderful flavor, texture, and nutrition to consumers.
Recent Breakthroughs
- Eat Just released their cultured chicken nuggets in Singapore and have gotten them approved for consumer use.
Read more
Immortalized satellite cell lines
We can now work around the replication limit by creating an immortalized satellite cell line through the addition of viral elements that alter cell cycle checkpoints such as SV40 or over-expression of telomerase. Researchers can create multiple cell lines and select the ones with the best characteristics in terms of cell division, protein expression, and taste to further optimize the production pipeline and final product.
These are not the same as cancer cells because the satellite cell lines will contain engineered methods to “turn off” the factors involved in immortalization. This will allow for a smooth transition from the stem cell to the mature skeletal myotube.
TL;DR
- It is very difficult for the whole world to get on board with going vegan. We need a new solution which is scalable and can produce animal products in an efficient way while reducing the effects of climate change.
- Cellular agriculture is an alternative solution that allows us to grow meat without having to slaughter an animal and improves the efficiency of the process. Cellular agriculture produces 91% less GHG emissions, needs 98% less water, and takes up 99% less land than traditional agriculture.
- Lab-grown meat is produced by:
- taking myosatellie stem cells from an animal through a biopsy
- adding growth medium that promotes proliferation and differentiation
- applying the cells onto a scaffold which helps provide the structure and texture of meat
- throwing the petri dish into a bioreactor which provides the ideal growing environment for the cells to grow into muscle tissue
4. Currently, scientists are working on finding a cheap plant-based alternative to FBS, reducing the cost of cultured meat, getting products FDA approved, and distributing it to customers.
Final Takeaways
To my fellow meat-eaters: you do not have to completely change your diet to save the world. The future of cellular agriculture will completely revolutionalize the way we eat and will help save our planet.
And, as the world of cellular agriculture improves, the taste and texture of cultured meat will be so similar to traditional meat that you won’t even notice the difference.
Hey there! Thanks for making it to the end of the article. Before you click out…
My name is Kimberly Liang (just call me Kim ☺️) and I’m a 16-year-old innovator/business enthusiast/musician who’s super interested in the future of biotech. I spend my time reading up on emerging technologies and training 10X mindsets.
If you want to find me:
Here’s my LinkedIn and Twitter. If you want to stay updated in my journey, sign up for my monthly newsletter!
Until next time 👋
For all you nerds out there 🤓: bonus resources for cell ag
General overview: https://www.new-harvest.org/cell_ag_101
Recent breakthroughs: https://www.new-harvest.org/current_research_projects
Companies doing cellular agriculture: https://www.cell.ag/companies
Technical articles:
https://link.springer.com/article/10.1007/s10584-020-02813-3
https://academic.oup.com/jas/article/98/8/skaa172/5880017
https://www.greenbiz.com/article/history-cellular-agriculture-and-future-food-too
https://www.frontiersin.org/articles/10.3389/fsufs.2019.00043/full
