Lab-Grown Breakthrough: Revolutionizing Cultured Meat with Authentic Fat Tissue and Texture

The discussion surrounding synthetic (or "cultured" meat) has gained momentum due to a breakthrough that could revolutionize large-scale production. A team of US researchers has successfully created lab-grown animal fat tissue with a texture and structure akin to natural meat. The study's findings were published in eLife.

At present, most cultured meat is produced as a cell mixture without structure (such as meatballs or chicken nuggets), making it challenging to create authentic steaks or chicken breasts. The true texture of meat, derived from muscle fibers, connective tissue, and flavor-enhancing fat, remains elusive.

Challenges in Lab-Grown Fat Tissue Production

Producing lab-grown fat tissue in significant quantities has been difficult because, as the fat mass expands, the central cells suffer from oxygen and nutrient deprivation and eventually die. In nature, blood vessels and capillaries transport oxygen and nutrients to tissues. However, replicating the vascular network in lab-produced tissue is currently impossible, resulting in muscle or fat tissue only a few millimeters in size.

A Novel Solution

To overcome this limitation, researchers cultured fat cells from mice and pigs initially in a flat, two-dimensional layer. They then harvested these cells, combining them into a three-dimensional mass with a thickener like sodium alginate or microbial transglutaminase (mTG) – both commonly used in food. As study coordinator John Se Kit Yuen Jr explains, "We thought that joining the cells after growth would suffice to reproduce the flavor, nutrient supply, and texture of animal fat." This method works when creating tissue solely for food consumption, as there is no need for the cells to remain alive once enough fat is present in the mass.

Testing Fat Cells: Pressure and Fatty Acids

To verify that the fat cells possessed the necessary characteristics, researchers conducted several experiments. One involved compressing cultured fat tissue to determine its pressure resistance compared to animal fat. They discovered that cells joined with sodium alginate withstood similar pressure to poultry and cattle fat, while cells joined with mTG behaved like rendered fat (e.g., lard or tallow). By using various thickeners and adjusting the quantity, it could be possible to mimic different meat textures.

Another experiment examined the molecular composition of fat tissue, revealing that the fatty acid mixture of cultured mouse fat differed from that of real mouse fat. However, the pork fat exhibited an acid profile remarkably similar to the original. According to the researchers, incorporating the necessary lipids into the cultured cells during growth could ensure that the final product closely resembles natural meat in terms of fatty acid composition.