“A microalga originally isolated from volcanic springs has all it takes to become the next ‘superfood’ on the market. Compared to Spirulina – a similar organism that’s been popular as a food and feed supplement for half a century – Galdieria is cheaper and easier to grow, and even more nutritious. In a closed-circuit reactor, it can convert organic waste into valuable proteins.
“Microalgae-based products have been around for a long time”, says Fabian Abiusi, a biotechnologist originally from Italy, “but in general, they are costly to produce. When these algae are grown in the dark, they convert only half of their organic substrate into biomass, while when they are grown under illumination and use carbon dioxide, they generally yield only low biomass densities. Both strategies require a costly system for efficient gas exchange.
As an added bonus, Galdieria turns out to be much richer in protein than Spirulina. Abiusi and colleagues discovered this by unravelling the full profile of the microalga’s amino acids – its protein building blocks. “Two thirds of Galdieria’s dry weight is amino acids”, says Abiusi, “which is more than is the case for meat, milk, cheese and eggs.” Specifically, the microalga contains much cysteine and methionine, two sulphur-containing amino acids, which it owes to its evolution in sulphur-rich volcanic springs.”