🍘 Aaruul

Aaruul is a Mongolian dried cheese. Sour milk or yoghurt is heated, the curd is pressed, cut or shaped into pieces and dried in the sun and wind, often right on the sloping roof of a yurt. Once dried, aaruul hardens and keeps for a very long time, so nomads have long taken it on journeys as a nourishing snack.

The tradition is ancient. Proteins in ancient people's dental calculus show that dairy foods were eaten in the eastern Eurasian steppe as early as about 3000 BC. Chinese chronicles from the time of the Xiongnu state (about 200 BC – AD 100) list dried cheese made from the milk of ruminants among the foods of the steppe peoples. Today Mongolia milks more animal species than any other country, and dairying is the main source of income for almost a third of the population.

Aaruul is most often made from yoghurt of cow's or yak milk; researchers also describe samples made from a mix of yak and cow milk. It can be sour or sweetish, with sugar and vanilla, shaped into bars, rounds or little figures. FAO describes a similar dried cheese of yak herders: the semi-dry kind contains 20–30% water, while the fully dried one has about 55% protein and 21% lactose; it is eaten as a snack with milk tea and stored in leather bags.

Aaruul or ordinary cheese? Aaruul is not ripened in a cellar. It is the curd of heated sour milk or yoghurt, pressed and dried in sun and wind until it turns hard, so by process it is nearer to dried curd than to a ripened hard cheese. Its closest relatives are kurt (qurut) from Central Asia and Iranian kashk: all are dried, strained fermented-milk curd, and they differ by region, shape and taste. Mongolian aaruul is often sweetish and comes as bars, rounds or little figures.

Look for the name “aaruul”, sometimes spelled “aruul” or written in Mongolian script, usually with “dried cheese” or “dried curd” on the pack. It comes as hard bars, rounds or small figures, sour or sweetened. Check the ingredient list for sugar and vanilla in the sweet kinds. You will mostly find it in Asian or Mongolian food shops, in specialist delicatessens and online, rarely in ordinary supermarkets.

Why it matters to you. Aaruul is a concentrated food: dry cheese is about half protein by weight, so a few pieces last a long time. It is very hard, so it is usually sucked. Sweet kinds contain added sugar, which you can see in the ingredient list. Aaruul's closest relatives are kurt (qurut) from Central Asia and Iranian kashk: all of them are dried, strained fermented-milk curd.