Making food out of thin air

IMAGINE a world where gas emitted from landfills can be turned into edible protein that ends up on your plate as a burger or a steak.

That's what scientists are hoping for. Calysta Inc in California and String Bio in the Indian city of Bengaluru are among biotechnology firms that have separately discovered ways to turn methane into protein. Bacteria found in soil are fed a liquid containing the gas, sparking a fermentation process similar to making beer. Instead of alcohol, protein is released into the water, which is then dried into a brown powder. The product is already being used in animal feed, the first step towards readying it for human consumption.

The companies are betting that their products would help alleviate the strain of a growing global population on agricultural land and oceans while natural gas prices trade near the lowest level in almost two decades. String Bio, a start-up which won US$200,000 in Indian government grants, and Calysta, backed by investors including Japan's Mitsui & Co and Cargill Inc, hope that methane-made protein would be…