The meat industry has been under fire recently because the public is learning more about how harmful mass production of meat is to the environment. This is one of the main reasons people choose to be vegan and it has gained a lot of momentum in the past couple of years. According to the Environmental Working Group (EWG), the production, processing and distribution of meat requires huge outlays of pesticides, fertilizer, fuel, feed and water while releasing greenhouse gases, manure and a range of toxic chemicals into our air and water.


Because the meat industry is so harmful to the environment, scientists have been trying to create lab-grown meat that is greener, more sustainable, and a more ethical alternative to traditional large-scale meat production. If scientists could make cultured meat that has the taste and texture of traditional meat, the results would be revolutionary.


There are many obstacles that scientists will have to overcome in order to get lab-grown meat from the petri dish to your refrigerator. The main problems they need to overcome are how to make large amounts of it, how to get it to taste like real meat, and how to recreate the texture of real meat.


They may already be on their way to recreating the texture and consistency. Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences have recently grown rabbit and cow muscle cells on edible gelatin scaffolds that mimic the texture and consistency of meat. This could mean that we may be able to still eat meat products without having to raise and slaughter animals. These findings were published in npj Science of Food.


Kit Parker, the Tarr Family Professor of Bioengineering and Applied Physics at SEAS and senior author of the study, said: “The materials-science expertise of the chefs was impressive."

“After discussions with them, I began to wonder if we could apply all that we knew about regenerative medicine to the design of synthetic foods. After all, everything we have learned about building organs and tissues for regenerative medicine applies to food: healthy cells and healthy scaffolds are the building substrates, the design rules are the same, and the goals are the same: human health. This is our first effort to bring hardcore engineering design and scalable manufacturing to the creation of food.”


The biggest challenge is trying to reproduce the long, thin animal fibers. Animal meat is made of skeletal muscle and fat tissue which grows in long, thin fibers. This can be seen when shredding pork or chicken.


“Muscle cells are adherent cell types, meaning they need something to hold onto as they grow,” said Luke MacQueen, first author of the study and a research associate at SEAS and the Wyss Institute for Bioinspired Engineering. “To grow muscle tissues that resembled meat, we needed to find a ‘scaffold’ material that was edible and allowed muscle cells to attach and grow in 3D. It was important to find an efficient way to produce large amounts of these scaffolds to justify their potential use in food production.”


In order to overcome these issues, the researchers used immersion Rotary Jet-Spinning (iRJS). According to Harvard, IRJS uses centrifugal force to spin long nanofibers of specific gelatin fibers to form the base for growing cells. The researchers spun gelatin fibers to form the base for growing cells. These fibers mimic natural muscle tissue’s extracellular matrix.


The research team seeded the fibers with rabbit and cow muscle cells which grew in long, thin structures, just like real meat. The researchers also tested and compared the texture to real rabbit, bacon, beef tenderloin, prosciutto, and other meat.


“When we analyzed the microstructure and texture, we found that, although the cultured and natural products had comparable texture, natural meat contained more muscle fibers, meaning they were more mature,” said MacQueen. “Muscle and fat cell maturation in vitro are still a really big challenge that will take a combination of advanced stem cell sources, serum-free culture media formulations, edible scaffolds such as ours, as well as advances in bioreactor culture methods to overcome.” Even so, this research shows that fully lab-grown meat could be the future.


“Our methods are always improving and we have clear objectives because our design rules are informed by natural meats. Eventually, we think it may be possible to design meats with defined textures, tastes, and nutritional profiles — a bit like brewing,” said MacQueen.

“Moving forward, the goals are nutritional content, taste, texture, and affordable pricing. The long-range goal is reducing the environmental footprint of food,” said Parker. “The development of cultured meat involves a number of technical challenges, including the formulation of a scaffold material that can successfully support cells and the development of cell lines that are amenable to cultivation for consumption at scale.”

“The authors of this publication have developed scaffold materials that show great promise in these areas,” said Kate Krueger, research director at the cellular agriculture research institution New Harvest.  

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