One scientist’s plan to make burgers and bratwursts from lab-grown bug cells.
By Marlene Cimons
Edible insects are a great source of protein. But it’s probably folly to think that more than a few people want to swap crickets for steak on the dinner plate. Chomping on a sautéed cricket or savoring a spoonful of caterpillar stew just wouldn’t be the same. Natalie Rubio, a doctoral student and researcher at Tufts University, thinks she has a better idea. She wants to use insect cells — not the actual bug — to grow muscle and fat in the lab and make food that tastes and chews like steak, chicken, lobster or shrimp — or anything else that pleases the palate.
“We end up with insect muscle and fat tissue, without insect legs, eyes and other crunchy bits,” she said. “Theoretically, we could produce a product that looks like steak, but is insect-based instead of cow-based.”
If humans ate crickets instead of cows, it would go a long way to slowing climate change. Cows and sheep fart and burp planet-heating methane, a heat-trapping gas many times more potent than carbon dioxide. Eating less meat also could help preserve forests, which are routinely cut down to create cow pastures.
Rubio believes, ultimately, that the concept will gain widespread acceptance. “In my opinion, if we can make tasty, healthy, affordable, sustainable and humane meat, consumers will be excited about it,” she said.
Rubio, who studies tissue engineering and cellular agriculture, began thinking about bug-based lab-grown food several years ago while working with insect cells for a different purpose. She was trying to make tiny robots powered by living muscles. It was during these experiments that she and her colleagues realized insect cells might make for a sustainable source of lab-grown meat.
“I started exploring growing insect cells for food,” she said. “Right now, we are making very small pieces of tissue because the even the small pieces can tell us a lot about how the cells are behaving… Right now, we work with fruit fly cells and caterpillar cells. You can take cells from any insect or other animals you are interested in.” Her study explaining the concept appears in the journal Frontiers in Sustainable Food Systems.
Insect cells already are in widespread use in the manufacture of drugs, vaccines and insecticides, so researchers already know a great deal about the process. Currently, scientists genetically engineer insect cells to produce proteins which are separated out from the cells and used in drugs and other products. Scientists already have been growing beef and leather in the lab. Rubio explained how they can apply the same techniques to making meat from insect cells.
“Instead of cells growing inside of animals and then slaughtering the animals to get meat, we recreate the conditions, outside of the animal, that cells need to grow into muscle and fat tissue, which is meat,” she said. “We take small amounts of tissue — think sesame seed sized — from donor animals, in my case, insects, and isolate the cells within the pieces of tissue that are able to multiply to create more cells.”
Rubio and her colleagues then feed the cells nutrients including sugars, proteins and vitamins to urge them to grow. “Sometimes these nutrients are obtained from animal sources, but we are working to get the nutrients from plant sources for sustainability reasons,” she said. “The cells will multiply in the nutrient soup and form tissues.” Moreover, they grow easily in the nutrient soup, which “makes it cheaper and easier to produce more of them,” she added.
Rubio said that scientists could also spur insect tissue to grow by exercising it. This isn’t like what humans do, lifting weights at the gym, but the end result is the same. Rather, the scientists would stretch the tissue, stimulate it with electricity or genetically engineer it so that it contracts when exposed to light. Doing so would make the tissue become “meatier,” thus improving its texture, she said.
“When we exercise, our muscles grow bigger,” she said. Exercise breaks down muscles, spurring them to grow to repair the injury. “ Just like exercise — that is, muscle contractions — makes muscles bigger in our bodies, we can simulate exercise to the muscle tissues we are culturing to make them larger and stronger,” she said. “Larger tissue means more meat, and stronger tissue affects the texture of the meat.”
Rubio said there are endless possibilities for making meat in the lab, whether from animal cells or insect cells, though challenges remain. “It is more straightforward to make processed meat products like hamburgers, hot dogs and nuggets, [but] more challenging to create structured meat products like steak, chicken breast and bacon, because it requires a specific orientation of the tissues,” she said. Eventually, the technology will progress to the point where it’s possible to make lab-grown bacon. Scientists could also dream up all-new meat dishes, as they are able to control meat at the cellular level.
Rubio said that lab-grown insect-based steaks and burgers will have to taste like meat if people are to eat them instead of a farm-raised cow. “Jelly beans taste good, but we don’t choose jelly beans over meat when we’re making choices about our diets because eating jelly beans is a totally different experience,” she said. “However, really impressive plant-based products like the Beyond Burger and the Impossible Burger are being chosen over animal-based burgers because they provide a similar experience. They satiate a craving. It’s OK if vegetarians and vegans don’t like cultured meat, because vegetarian diets are already pretty sustainable. Cultured meat should be a more sustainable option to farmed meat while providing a similar culinary experience.”
Yet, she adds, vegetarians need not shun a bug-based burger, or any other meat made from cultivating insect cells. “Because we are using insect cells, but not whole insects, vegetarians who approve of cultured beef for ethical reasons would also approve of cultured insect meat,” Rubio said. “The original cell source comes from insects, but after the initial cell acquisition, we don’t need to use insects, so they are not harmed.”
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