Roslin Institute’s FaTTy cells could streamline cultivated meat fat production

A new line of pig-derived fat cells developed by scientists at the Roslin Institute could help address one of the cultivated meat sector’s biggest challenges: producing realistic, scalable, and ethically sourced animal fat without relying on gene editing or animal-derived additives.

The research team, based at the University of Edinburgh’s Royal (Dick) School of Veterinary Studies, has successfully cultivated a unique population of pig stem cells that can proliferate indefinitely while retaining the ability to transform into fat cells. Known as FaTTy, the cells are seen as a potentially vital tool for delivering the flavor and texture consumers expect from meat products, especially in a market where animal fat plays a central role in taste and mouthfeel.

“This discovery represents a significant step forward in a global market estimated to grow by between US$5 billion and US$30 billion by 2030,” the Roslin Institute noted.

Unlike typical livestock stem cells, which tend to lose their fat-producing capacity after a limited number of divisions, the FaTTy cells maintained both their proliferation and differentiation capabilities through multiple generations in the lab. According to the researchers, this dual capability is rare and makes the cells especially suited for large-scale use in cellular agriculture.

“We didn’t simply develop a tool, we made a very special discovery,” said Dr Tom Thrower, the lead researcher behind the study. “The fact that these cells not only grow indefinitely but also retain their ability to become fat at such high efficiency is something we have never seen before in livestock stem cells. It opens the door to new possibilities in cultivated meat and beyond.”

The work is particularly noteworthy because the pig fat cells were developed without the need for genetic modification. This addresses a long-standing regulatory and consumer perception hurdle in the cultivated meat industry, where genetically modified ingredients remain controversial in many markets.

The researchers initially grew stem cells from five different piglets but found that only one cell line could replicate hundreds of times while maintaining the capacity to differentiate into fat cells. The resulting fat tissue closely resembled native pig fat in its biochemical composition, with one notable difference: it contained slightly higher levels of monounsaturated fats, which are generally considered healthier.

“The outcome helps meet the need for fat as a key component in delivering the flavor and texture that consumers expect from meat,” said Professor Xavier Donadeu, Principal Investigator at the Roslin Institute. “These fat cells have the potential to be a game-changer in the field of cultivated meat, and help make this a reality in the very near future.”

One of the core issues facing cultivated meat producers has been how to develop fat that mimics the sensory experience of traditional meat. While muscle tissue is often the focus of cultivated meat research, fat plays a critical role in flavor release, juiciness, and overall consumer satisfaction. However, most existing systems struggle with producing consistent fat at scale, particularly when avoiding gene editing or animal-derived serum.

The new FaTTy cells address both of these issues by offering a stable, reproducible source of animal fat that is not only unmodified but also grows indefinitely under lab conditions. As a result, the cells could serve as a dependable input for meat developers looking to blend lab-grown fat with cultivated muscle to replicate conventional meat products more closely.

In addition to publishing the findings in NPJ Science of Food, the Roslin Institute is sharing the FaTTy cell line with academic institutions and industry stakeholders to accelerate progress in the cultivated meat field and promote further research into fat biology. The Institute receives strategic investment from the Biotechnology and Biological Sciences Research Council (BBSRC), a key UK government funding body for bioscience research.