A drink shaped by the milking season
In Mongolia, fermented mare’s milk is known as airag. Its production follows the rhythm of herding: mares are milked repeatedly during the warm season, and the fresh milk is fermented rather than stored for long periods as it is. That makes airag a distinctly seasonal food, tied to the time when herds are producing milk.
From milk to a lively, sour drink
Fermentation is the work of naturally occurring microbes. Some turn milk sugar into lactic acid, which gives airag its sharp, tangy taste; others produce alcohol and carbon dioxide. The trapped gas creates its gentle fizz. The drink is not distilled, and its alcohol content can vary with how it is made and how long it ferments.
Traditionally, the milk is kept in a container and stirred or churned repeatedly as it ferments. This keeps the mixture moving while microbes transform it, helping produce a drink that is tart and lightly foamy rather than simply sour milk.
More than a novelty
Airag belongs to a broader Mongolian herding tradition in which milk is made into foods and drinks suited to a pastoral way of life. Its brief season and fresh, fermented character connect it closely to the animals and the work of tending them. A cup is therefore not just an unusual taste for visitors: it is a drink whose arrival signals that summer’s milking is underway.
