What would beer be like if it was brewed on a generation ship?

Humans have been fermenting grain-flavored liquids into some simulacrum of beer for more than 10,000 years. And so it stands to reason that, over the next 10,000 years, we'll continue finding ways to combine water and yeast with some kind of sweetener and a floral bittering agent, whether out of some adherence to tradition, or just to take the edge off of after a long day of galactic work.

Over at Tor.com, novelist Arkady Martine, author of the celebrated space-operaA Memory Called Empire, decided to take the thought of space beer and follow it all the way to its logical potential ends. How,exactly, would one be able to brew beer in the confines of a spaceship, using only the basic knowledge that we currently possess around the science of agriculture and fermentation?

Ingredients necessary for beer: water, yeast, and a starch that the yeast can work upon.

Ingredients you want if youd like your beer to taste vaguely like the beer we know: malted barley, hops.

Lets start with yeast. The usual yeast is abrewers yeast, most oftenSaccharomyces cerevisiae, which happenshelpfullyto be the same species as the yeast that makes bread rise. Yeasts are little live creaturessingle-celled microorganisms that love to eat sugars and transform them into carbon dioxide and alcohol. They need to bekeptalive. A generation ship would have had to bring a yeast colony, perhaps in the form of a sourdough starter, and feed it regularly with starches and sugars, in order to be able to have a steady supply of small organisms to brew beer with.