Feeding Fish with Methane?

Our last post on farmed fish revolved around grubs – dried black soldier fly larvae – as an alternative and more sustainable feed in aquaculture. Today I learned about yet another method for feeding fish that doesn’t involve catching wild fish or using petroleum-reliant grains, and actually helps control a problematic greenhouse gas, methane. Kristine Wong writes for Civil Eats, a website that acts as a “daily news source for critical thought about the American food system”:

Wild seafood is disappearing rapidly and many consumers have turned to farmed fish as a way to help reverse the trend. But finding a sustainable source of food for carnivorous fish such as salmon and tuna—which rank as the second and third most popular types of seafood in America—has been a persistent challenge for aquaculture producers.

Now, a group of scientists have developed a new form of fish feed that uses no agricultural land and requires very little water. It’s called FeedKind and it’s made from bacteria that eats methane and turns it into energy.

This approach is promising because for a long time fish farms merely fed these fish a diet consisting of wild “forage” fish and oil derived from wild fish. But it often took several pounds of wild fish to produce 1 pound of farmed fish, making it a loss for the oceans.

Then, in recent years, the aquaculture industry turned to feed based on corn, soy, and wheat, usually using dried distiller grains. While these solutions are often better for the oceans, they also rely heavily on agricultural land, much in the way other animal feed does. Similarly, they rely on the use of pesticides and synthetic nitrogen fertilizer, which contribute to “dead zones” in the ocean.

“We’re taking carbon from outside the food chain, which frees up more food for humans,” says Josh Silverman, the founder and chief products officer of Calysta, a biotech startup in Silicon Valley. “And we’re turning methane into a higher value product.”

Calysta says FeedKind could address sustainability problems plaguing aquaculture, which the Food and Agricultural Organization found is one of the fastest-growing agricultural industries worldwide.

After raking in $30 million of capital from investors in a third round of funding—including animal feed giant Cargill—since December, Calysta is readying a R&D plant in England that plans to manufacture FeedKind at pilot scale by the end of this year. It’s also hoping to get a North American commercial production facility online by 2018.

FeedKind is made by first dissolving methane in water with the bacteria (methanotrophs that are commonly found in the top layer of soil). The bacteria gobbles up the methane molecules. Then, after the mixture is fermented, the protein produced from this process is extruded and formed into pellets.

“[People] have known about this bacteria for years,” says Silverman, who has a Stanford PhD in biotechnology and comes from the biopharmaceutical industry. “But no one had thought about how to use them in industrial applications.”

The alternative fish feed was originally developed over a decade ago by Norferm, a Norwegian company that won approval to sell FeedKind in the European Union. After Calysta acquired the company in 2014, Silverman says he refined the fermenting process.

Norferm only tested the product in salmon. But Silverman claims that FeedKind could also be used to feed other carnivorous fish such as halibut, sea bass, sea bream, eel, and shrimp—perhaps even terrestrial livestock and pigs, he adds.

Jan Brekke, the CEO of Sogn Aqua, a sustainable halibut farm in Norway, says he has not tested FeedKind on his fish, but is encouraged by its potential.

“The whole idea of [not] using biomass from the sea to produce fishmeal will turn global fish farming in a total different direction,” he said in an email.

FeedKind is not an environmentally pristine product. For one thing, carbon dioxide is released into the atmosphere during the fermenting process. And Silverman says that Calysta plans to source the methane for FeedKind from natural gas extracted from the electricity grid rather than capturing it from the atmosphere. (Methane is a significant component of natural gas).

Read the rest of the original article here, and check out a piece from The Guardian on the topic that we missed in March.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s