Like cell-cultured meat companies, TurtleTree Labs - which makes the key components of human breastmilk by culturing mammary cells in a bioreactor - also relies on cell culture media and growth factors to make its milk.
Its team “has been focusing on the development of high quality, high volume and cost-efficient growth factors that the company needs,” said the firm, which has offices in Singapore and San Francisco.
“Leveraging the know-how of their in-house production, the company is now launching [new division] TurtleTree Scientific to play a major role in addressing this crucial need."
TurtleTree Scientific will work with cell-cultured meat companies on the production of food grade growth factors, with prices “expected to be a fraction" of pharmaceutical grade equivalents on the market.
“Not only are we collaborating with local research institutes like NUS and NTU, but also global institutions like Wageningen University in the Netherlands," said chief strategist Max Rye.
"We have already started sending some samples to other cell based meat companies and aim to play a major role in this industry."
Novel microbial expression system
Cell signaling molecules that play important roles in cell proliferation and development, growth factors can be "secreted by neighboring cells, distant tissues and glands, or even tumor cells themselves," Harith Bahren, business development co-lead told FoodNavigator-USA.
TurtleTree, however, is using a novel microbial expression system to produce growth factors, although it is not sharing which ones it is concentrating on at this stage, he said.
"There are differing components inside each growth media formulation specific to the different needs of the cellular agriculture companies. We will announce our product offerings in near time."
Asked why growth factors are currently so expensive, he said: "Cell culture media components have been developed for their applications in research and therapeutics. These applications do not have the same high cost constraints that apply to food and agriculture, but costs can be lowered through raw material and manufacturing standards that will be sufficient for food production.
"The production of cellular agriculture and the need for these components, will also be at a scale much greater than current therapeutic applications. Hence, there is great potential for reaching economies of scale."
Memphis Meats VP: 'We aren’t stuck with the ridiculous catalog prices we see in research today'
When it comes to the raw materials needed to feed the cells at different stages of their development, researchers in the nascent cell-cultured meat industry “may be ordering components for their cells in 500g bottles, but eventually we need to be talking about rail cars and barges to get the raw materials we need to make meaningful amounts of meat,” said KC Carswell, PhD, VP process development at startup Memphis Meats during a keynote speech at the Cultured Meat Symposium in October 2020.
And while amino acids such as lysine, methionine and glutamate are already made in large quantities (often via fermentation for the animal feed industry) at “prices of approximately $1 per kilo,” growth factors also needed in cell-cultured meat production are considerably more pricey, she said.
“For example, if you’re purchasing FGF - a protein often required by some of our meat cells - from a catalog provider, the price is about $800,000 a gram.”
By contrast, pricing for industrial enzymes used in laundry detergents is a more palatable $10 a kilo (or thereabouts), and yet they’re all proteins made recombinantly, she noted. “So there’s work to be done here.”
Going forward, she added: “We might require additional purification steps to clean up those crude proteins for cell culture use, but we aren’t stuck with the ridiculous catalog prices we see in research today. We need to find clever process solutions and cell feed formulations to ensure we’re translating our raw materials into meat in the most cost-effective ways.”
It's milk, but not as we know it, Jim...
Several companies are now engineering microbes to produce components in cow's milk (Perfect Day in Emeryville, CA; New Culture in San Francisco, CA; Remilk in Israel; Legendairy Foods in Germany, and Those Vegan Cowboys in Belgium); while others are using microbial hosts to express components in human breastmilk such as proteins or human milk oligosaccharides (HMOs), that can be added to infant formula.
However, TurtleTree Labs (and fellow startup US-based BIOMILQ) are culturing human mammary cells that produce ‘real’ breastmilk.
The composition of the milk is not identical to breastmilk produced in the body because the cells may not be exposed to all of the antibodies and other components circulating in the mother’s blood (so TurtleTree Labs' milk doesn't contain immunoglobulin, for example).
However, it’s closer to the real thing than any formula on the market today, and offers millions of women that either cannot breastfeed, or are unable to breastfeed for as long as they would like, something they can feel good about, co-founder Max Rye told FoodNavigator-USA in a recent interview: "We don’t want to encourage anyone to stop breast feeding."