Cellular Agriculture: What is it precisely, and how can we leverage this technology? š§
An intensive guide outlining everything you need to know
I recently got fascinated by Cellular Agriculture and published an article to portray the potential that harnessing this technology holds. You can check out that article here :
In this article, we will take a deep dive into the actual science that takes place for Cellular Agriculture while also talking about the limitless applications that this technology holds, so buckle up your seatbelts because you are in for a ride. š¢
Introduction
If you read the previous article, which you can find here, you probably already have a very brief understanding of how this technology works. But letās refresh the basics of cellular agriculture and what the end goal is.
As you well know, climate change is a global issue that we are trying our best to solve. California shouldnāt be blanketed in smoke caused by wildfires; Greenlandsā ice sheets shouldnāt be melting; temperatures shouldnāt be rising at such an accelerated rate. But alas, all of this is happening due to our intensive use of land, water and other natural resources, to keep up with the constant increase in population.
The United Nations predicts that by 2050 we will have a staggering population of about 10 billion people.
This will lead to more demand for food and resources, which by looking at the rate we are currently utilizing these resources wonāt be enough to sustain a growing population.
Fun fact: This year, Earthās overshoot day was August 22 which marked the date when we had exhausted all of natureās resources for the year meaning that for the rest of the year, we are actually going to be in an ecological deficit by using more resources than the Earth can handle and accumulating more carbon dioxide in the atmosphere. Learn more here: overshootday.org
Raising livestock requires a lot of land and demands lots of water and food, which takes up a lot of resources. Irrigation systems are also very inefficient, and agriculture contributes to greenhouse gas emissions leading to climate change.
But itās not like we canāt sustain enough resources to feed 10 billion people. The problem is that even with 7 billion people right now, we are struggling with world hunger and poverty as we are wasting so much of it. For instance, every Canadian loses or wastes about 400 kilograms of food per year.
The solution to this is also relatively simple to understand but challenging to execute, DONāT WASTE FOOD. The amount of food going to waste right now is enough to feed 1.5x the amount of our population.
We need to produce all our delicious animal products by using sustainable methods like cellular agriculture. To refresh, cellular agriculture is the production of agricultural products using cells.
Now letās see what the science behind the scenes is.
Environmental Prospects of Cultured Meat š³
One of the main focuses of cellular agriculture is to produce the same meat that you would traditionally get from growing livestock but utilizing a small number of their cells. This will use a fraction of the land, water and other resources that it takes to produce the same products through traditional agriculture. Making cultured meat produces almost no methane, which is a greenhouse gas that is released by cattle and stays in the environment for approximately 12 years. Thus far, the process of growing cells for meat production relies on energy resources that emit a significant amount of carbon dioxide. Although this can be alarming at first glance, we need to remember that many breakthroughs are being made in the energy sector that produces almost no carbon dioxide and are more sustainable.
But how does the meat grow? š
To answer this, we need to understand what meat consists of, which is about 75% water, 20% protein and 5% fat and carbohydrates. The muscle is a collection of many tiny cells called myofibrils or myofibers, which have two main proteins: actin and myosin. These proteins are essential in the movement of the cells as they convert chemical energy like ATP to mechanical energy that generates the force required for the activity of the cells. These proteins are made up of organic compounds known as amino acids, which mainly consist of nitrogen, oxygen, hydrogen and carbon molecules. At the same time, fat cells act as a reservoir of energy. The fat consists of glycerol and fatty acids, which are essential for cells to absorb nutrients and produce hormones.
To grow the muscle tissue, though, we need to extract a rather particular type of cell known as stem cells. These āspecialā cells are unspecialized cells that can divide and transform in any other building block ranging from brain cells to muscle cells, making them very unique.
So now that we know what meat consists of and what cells need to be used letās talk about how it is grown.
To produce meat, stem cells would need to be extracted from the animal. Then we manipulate them to grow in a bioreactor tank that would mimic the natural environment of the animalās body. Cells will replicate in the necessary heat, oxygen, salts and proteins that they need to transform into muscle tissue just like in the animal itself. This process is known as myogenesis, which in a nutshell, is collecting cells that can become muscle tissue, which is then introduced to the necessary nutrients required to grow into small myotubes, which become myofibers, which, as we know, make up the muscle tissue.
On top of that, other cells (i.e., fat cells) are usually also introduced to make the meat juicy and tender, so it mimics the actual flavour of meat obtained from animals.
Letās break this down into smaller segments :
Step 1: Extract cells from š
As we know, to grow the meat, we will need to extract cells from the animal. Cows have lots of muscle tissue that have special sections on top of this tissue in case they need more muscle. These special cells are the main ingredient for the lab-grown meat, and so these cells can be extracted and later proliferated to produce tons of burgers. š
This is all we need from the cow in this process, and it can go running in the field living a happy life, not fearing death. No animals are harmed at all.š
The most common type of cell used in cultured meat is a muscle stem cell, also known as a myosatellite stem cell.
These special cells are multipotent, meaning they can only evolve into muscle cells and nothing else, making them easier to control in a lab environment. One thing to keep in mind is that these cells also age as each time they divide, a bit of DNA is lost, meaning that the cells can only replicate a certain amount of times before it will undergo apoptosis or programmed cell death. This concept is known as the Hayflick Limit.
Other cells like iPS cells (Induced Pluripotent Stem Cells) or Embryonic Stem Cells can also be used to culture meat. These cells are pluripotent, which means that both types of cells can become any cell in the body. Whereas, multipotent cells like the one found in the muscle tissue of the cow can only become muscle cells. This allows the pluripotent cells to be able to divide indefinitely as they donāt have a Hayflick Limit meaning that one of the iPS or Embryonic Stem Cells can feed the world forever, in theory.
These āspecialā cells are the only ones that can divide indefinitely besides cancer cells, making them very unique, allowing them to create infinite identical copies of themselves.
But the reason they are not widely used to culture meat is that they are incredibly hard to control. Ongoing research is currently taking place to hold the differentiation of these cells.
When using pluripotent stem cells to culture meat, two things need to be kept in mind :
- Proliferation (Multiply in population, easy as they can make infinite identical copies of themselves)
- Differentiation (Mature; the process in which the cells changes from one type to another or specializes to a kind)
Therefore, multipotent cells extracted from the muscle tissue are much easier since they will only become muscle tissue.
Step 2: Allow the cells to proliferate and differentiate. š§«
Once we have the cells, we need to allow them to multiply in population so we can use it to culture meat. So how is it done?
Using a growth medium š„
As we know, cells are also living and need fuel or food to get work done. When they are in our body, all the nutrients we get allows them to function, but once they are in a lab environment, we need to get creative.
So to give them the required fuel, the cells are soaked in a āgrowth medium,ā which is rich in amino acid and nutrients that can allow the cells to proliferate and differentiate.
The current growth medium being used is known as FBS (Fetal Bovine Serum) that is extracted by killing a fetal calf by inserting a needle into its heart. As an animal is still being killed in the process, many researchers are currently finding an alternative to this serum.
Furthermore, this medium is also incredibly expensive and simply impractical and, in my opinion, unethical.
Therefore, this serum is a no-go, and we need an alternative.
Stay tuned for my next article, where I go more in-depth about this topic and talk about what New Harvest researcher Cameron Semper is working on to address this issue.
Step 3: Utilize the cells to form structures š
Before we get into how we can create the actual meat, one crucial aspect of this process is the growth of cells.
Cells are like a thin 2D surface, so when meat is cultured, they grow into these two-dimensional strips, and so we need to form a 3D structure to produce, letās say steak!
To form these 3D structures, we utilize scaffolds that create more surfaces on top of the body that the line of cells already occupies, making a three-dimensional structure. A bioprinter is used to support the stands and allow the cells to grow to form a 3D tissue. Itās very much like an inkjet printer, but instead of ink, we are using the 2D cell strips that are layered on top of one another, creating this masterpiece. But since our techniques are still in its early days, complex structures like cultured steaks are hard to produce.
So once these cells (myofibers) are grown, other ingredients like fat cells can be added to add the taste of traditional meat.
Challenges of Cultured Meat š
The main reason why cultured meat is not commercially available like plant-based meat products is that several caveats need to be addressed before this a reality. Some of them being :
1.) The Use of FBS in the growth medium š§Ŗ
Current cultured meat production is far from perfect as the serum we rely on to allow the cells to grow is incredibly expensive and is derived from animals, which are very counterintuitive as the whole point to produce cultured meat is not harming any animals and increasing access to food.
Sidenote: Another important aspect to keep in mind is that we need the cells to differentiate and proliferate which each requires different nutrients and/or chemicals. It is difficult to determine how many media should be used for each task as culturing meat is very expensive š°
2.) Perfecting the taste of cultured meat š
For the people to accept clean meat and for it to survive the market, it needs to taste like meat. Researchers are working on improving the taste and texture of the beef, while AI algorithms are being developed to test different compounds that affect the taste and texture of the meat. There is a lot of research currently being done in the field of flavour engineering and also in studying the smell-flavour perception or the aroma.
3.) An efficient method of constructing cell structures š¬
Currently, we use diffusion to feed the cells, which is why we are limited to producing hamburgers or thin sheets of meat. Diffusion is the movement of substances from a high area of concentration to a low area of concentration, which makes feeding the cells an ongoing problem with making thicker structures like steaks because, at a specific point, diffusion stops working. This is because a cell needs to be 200 microns to form nutrients, which in the process also limit the cultured meat products to be a maximum of 200 microns that is comparable to the thickness of the width of a human hair.
4.) Controlling pluripotent stem cells š§«
As we know, instead of using the multipotent stem cells found on the muscle tissue of the cow, we can also use other pluripotent stem cells. Embryonic stem cells or iPS cells, which donāt have a Hayflick Limit, thereby can divide indefinitely. However, what makes them hard to control is that they can specialize into any tissue, making the differentiation step of the cells difficult as they need to be redirected into muscle cells like the multipotent stem cells become.
Aside from these, there are many other challenges like consumer acceptance as well as food regulations and scaling manufacturing so that it can be produced in mass quantities.
This may all seem complicated, but it can be summarized in this one diagram.
Fun fact: A 3-ounce burger requires 10,000 of these strips
See pretty simple right?
Even though there are these challenges that we have to overcome, cultured meat has tons of great opportunities to solve current posing issues while also making cultured meat production the primary method of getting meat, keeping animals unharmed and eventually in the future causing the cost of meat to drop down. This will allow us to enjoy meat guilt-free while allowing the animals to thrive and our Mother Earth to flourish. š
If you have made it to the end of this article, please share it with your friends to bring awareness about this field and spread the word about this fascinating topic.
This article is one of many developed to broaden your understanding of this field with loads of groundbreaking research and developments.
About the Author :
Zaki is an ambitious student who is currently working with Cellular Agriculture Canada to look into the field of Cellular Agriculture in means of educating todayās youth about this exciting field.
To learn more about Zaki, visit https://zakirangwala.com//.
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