In a significant step forward for the cultured meat industry, scientists have successfully achieved large-scale production of lab-grown adipose tissue that closely mimics the texture and composition of naturally derived animal fats. The groundbreaking findings, recently published in the journal eLife, offer promising prospects for the creation of cell-cultured meat with enhanced taste and texture, closely resembling traditional meat.

Cultivated meat has been garnering attention as various startup companies worldwide delve into the development of cell-grown chicken, beef, pork, and fish. However, most of these endeavors are still in early stages, not yet ready for large-scale production, and only a few have received commercial approval. The existing products mainly consist of unstructured mixtures of cells, lacking the texture found in real meat, which is created by muscle fibers, connective tissue, and fat—the latter being a crucial factor contributing to meat’s flavor.

Consumer testing has demonstrated that beef with a higher fat content, specifically around 36%, receives the highest scores. Nevertheless, producing cultured fat tissue in sufficient quantities has proven challenging due to the fact that as the fat grows into a mass, the cells in the core become deprived of oxygen and nutrients. In nature, blood vessels and capillaries deliver essential elements throughout the tissue. However, replicating this vascular network at a large scale in lab-grown tissue remains an unresolved issue, limiting the size of muscle or fat that can be grown to a few millimeters.

To overcome this obstacle, the researchers initially grew fat cells from mice and pigs in a flat, two-dimensional layer. Subsequently, they harvested these cells and aggregated them into a three-dimensional mass using binders such as alginate and mTG, both of which are already used in some food applications.

“Our aim was to develop a relatively simple method of producing bulk fat. Since fat tissue primarily consists of cells with few other structural components, we believed that aggregating the cells after growth would be sufficient to reproduce the taste, nutrition, and texture profile of natural animal fat,” explains John Yuen Jr, a graduate student at the Tufts University Center for Cellular Architecture (TUCCA) and the first author of the study. “This approach works well when creating tissue solely for food since there is no requirement to keep the cells alive once we gather the fat in bulk.”

The aggregated fat cells immediately exhibited the appearance of fat tissue. To verify whether they truly replicated the characteristics of native animal fat, the team conducted a series of additional experiments. They investigated the texture by subjecting the fat tissue to compression and measuring its ability to withstand pressure compared to natural animal fat. The results showed that cell-grown fat bound with sodium alginate could endure a similar amount of pressure as fat from livestock and poultry. Conversely, the cell-grown fat bound with mTG behaved more like rendered fat, akin to lard or tallow. These findings suggest that it may be possible to fine-tune the texture of cultured fat by using different types and quantities of binders to best resemble the authentic texture of fat within meat.

During cooking, numerous compounds are released, contributing to the flavor of meat. Many of these compounds originate from fat, including lipids and fatty acids. Therefore, the researchers examined the composition of molecules in the cell-grown fat and found that the mix of fatty acids in cultured mouse fat differed from that of native mouse fat. However, the cultured pig fat exhibited a much closer fatty acid profile to its natural counterpart. These preliminary findings indicate the potential for supplementing growing fat cells with the required lipids to ensure a closer match in composition to natural meat.

By Impact Lab