Producing meat from animal cells, without the need to rear and slaughter animals, is one of the promises of cell-based agriculture. However, for this technology to be viable on a large scale, two practical challenges must be overcome: how to grow large quantities of cells efficiently, and how to harvest them at the end of the process to incorporate them into cultured meat products.
A new study, published in the journal Innovative Food Science and Emerging Technologies, has Hélder Bandarra-Tavares, a PhD student at CCMAR who is working in collaboration with the Institute of Bioengineering and Biosciences at the Instituto Superior Técnico (iBB-IST), as the lead author. The study was supervised by Profs Pedro Fonte and Ana Fernandes-Platzgummer. It combines principles of cell biology, biomaterials and bioprocessing in order to support the transition from animal cell culture to scalable, industrially relevant systems.
The process of creating cultured meat begins with the collection of animal cells, which are then multiplied in a laboratory environment.
Like many cells in the human body, the cells used in this study require a solid surface to which they can attach in order to grow. These cells are known as 'adherent' cells.
Microcarries act as a support for these cells, allowing them to multiply on their surface. The microcarriers are then used in suspension cell culture systems, which allow production on a scale closer to that of industrial processes.
In this study, cell production was carried out in a stirred culture system similar to those used in industrial bioreactors, but on a smaller scale.
The researchers worked with cells derived from the umbilical cord of a cow.
This tissue was chosen because it contains many cells with high proliferation potential, and because obtaining it does not involve slaughtering the animal. This promotes a process for producing cultured meat that focuses on sustainability and animal welfare.
In this study, the team isolated cells from three different animals and tested various culture conditions to optimise growth. One of the most significant findings was the effect of FGF-2, a growth factor. Adding it to the culture medium approximately doubled the number of cells produced, thereby making the process more efficient.
But the real innovation of this work lies in the way the cells are harvested once they have grown.
Traditionally, separating cells from microcarriers is a complex process that can result in cell loss, thereby compromising its efficiency, particularly on a large scale. In this study, however, the researchers used a pectinase-based solution to dissolve the microcarriers and release the cells intact. This method enables the recovery of cells with a high yield, overcomes key obstacles to the process's scalability and allows large quantities of cells to be obtained. Producing a microparticle-free cell suspension at the end of the process facilitates its direct application in cultured meat and allows the product formulation to be easily adjusted.
Furthermore, tests showed promising results: the cells adhered with high efficiency and began to proliferate immediately without requiring an adaptation phase. After seven days of culture, the number of cells had increased by between eight and nine times, demonstrating the success of the implemented conditions. This system also has the potential to be applied on a larger scale, representing a significant advance in the large-scale production of animal cells.
“This publication shows how knowledge traditionally used in the biomedical and pharmaceutical sciences can contribute to new areas such as sustainable food systems, alternative protein production and next-generation biotechnology.”
While the path to industrial scale is now open, challenges remain.
The authors acknowledge that the proliferation capacity of these cells is limited for large-scale production. However, the study establishes a platform that can be optimised in future research.
Demonstrating that microparticles are effective for this type of cell and that scalable culture systems can produce them reproducibly and efficiently represents an important step in developing processes for cellular agriculture.
