Researchers at UCLA have created an edible particle that helps make lab-grown meat, known as cultured meat, with more natural muscle-like texture using a process that could be scaled up for mass production.
Led by Amy Rowat, who holds UCLA’s Marcie H. Rothman Presidential Chair of Food Studies, the researchers have invented edible particles called microcarriers with customized structures and textures that help precursor muscle cells grow quickly and form muscle-like tissues. Edible microcarriers could reduce the expense, time, and waste required to produce cultured meat with a texture that appeals to consumers. The results are published in the journal Biomaterials.
“Animal cells that can be coaxed to form tissues similar to meats could offer a protein source to a world facing food insecurity caused by threats ranging from epidemics to natural disasters,” said Rowat, who is an associate professor of integrative biology and physiology at the UCLA College. “Cultured meat products are not yet on the market in the U.S., and strategies to enable mass production are still emerging.”
Mass production of cultured meat will involve surmounting several challenges. Current methods can produce a cultured steak that mimics the structure of T-bone, but not at the volume needed for food production. In an animal’s body, the muscle cells most commonly eaten as food grow on a structure called the extracellular matrix, which determines the shape of the mature tissue. Animal tissue can be grown in a lab using scaffolds made from collagen, soy protein or another material to replace the extracellular matrix. This process, necessary to produce whole tissues resembling steaks or chops, is labour intensive and takes weeks, making it hard to scale up for industrial production. It takes about 100 billion muscle cells to produce a single kilogram of cultured meat.
Growing larger volumes of cultured meat at a faster pace involves making a paste or slurry of cells in a container called a bioreactor. Unfortunately, without a stiff substrate, meat grown this way lacks the muscle-like structure and therefore, texture and consistency, of what people are used to eating.
Current types of microcarriers can be used to provide a scaffold to which cells can attach, and to organize suspension-grown tissues, but they are inedible and must be removed from the meat before consumption.
UCLA’s microcarriers can be eaten along with the cultured meat they help grow. The structure and texture of microcarriers could be tuned to speed up the growth of muscle tissue and to optimize meat texture, Rowat said. The edible microcarriers also supported growth of bovine muscle cells and yielded beef that browned nicely when cooked.