Qurut

quroot · kashk · qurt

Summer's yoghurt, kept for the cold months.

What it is

Qurut is yoghurt taken as far as it will go. It is strained through cloth until thick, salted, rolled into balls or pressed into cakes, and dried in the sun until hard and chalky white. In that state it keeps for months. To use it, the pieces are soaked in warm water and rubbed until they dissolve into a thick, sour, salty cream, sharper than any fresh yoghurt.

Where it comes from

Dried sour dairy is made across the herding country from the Caucasus to Mongolia, wherever milk comes in a summer glut and has to last a winter. Afghan families make it at home and buy it in the bazaar, and the same product is kashk in Iran, qurt in Kazakhstan and aaruul in Mongolia, each with its own shape and degree of sourness.

What it's called

Qurut or quroot (Dari and Pashto) · kashk (Persian) · qurt and kurut (Turkic languages). Chaka, the strained yoghurt it starts from, is a separate and fresh product. The liquid kashk sold in jars in Iranian shops is the same thing already reconstituted.

In the kitchen

Reconstituted qurut is a sauce and a seasoning at once. It fills the well in kichiri quroot, the sticky rice named after it, and it is stirred through mastawa at the end of cooking. Families with a stock of it reach for it wherever a sharp dairy sauce is wanted. It is salty as well as sour, so salt the dish after the qurut is in, not before. Strained yoghurt with a squeeze of lemon is the usual stand-in, and our recipes use it while noting where qurut belongs.

What we know about the claims

It is concentrated dairy: high in protein and calcium, and high in salt, which is what preserves it. Anyone watching their sodium should taste before adding more salt to a dish that carries it.

Choosing and buying

Afghan grocers sell dried qurut in balls; Iranian grocers sell kashk dried and, more often, liquid in jars, which is the easier buy and goes straight into the pot. In the UK, try the Afghan grocers of Southall, Hounslow and Ilford or a Persian shop; in the US, every Persian grocer carries jarred kashk. Refrigerate liquid kashk once opened. Dried balls keep for months in a sealed jar.