Sour. Salty.

Horse milk.

High up in the Tian Shan mountains of Kyrgyzstan, people milk horses. They ferment the milk to make a drink called kumis.

Would you take a sip?

Kyrgyzstan’s kumis makers belong to tribes that move around. They have relied on kumis for nourishment for hundreds of years.

Connoisseurs say the best kumis of all comes from part of Kyrgyzstan called the Suusamyr valley. In winter, deep snow covers the valley. When the thaw comes, all that melted snow feeds the growing grass and herbs. By the end of summer, the valley is awash in a thick, emerald carpet of juicy blades of grass. Well, juicy if you’re a horse!

The horses devour the foliage. These plants flavor the milk they make. Locals gather the milk. The milk then is left to ferment, or sometimes churned to promote fermentation. Eventually, it becomes alcoholic—but just a little bit.

Rustam Tukhvatshin is a Kyrgyz medicines professor. He says kumis helps blood cells grow and pushes toxins out of the body. He says he never misses coming to Suusamyr during kumis time.

Tourists and people from other parts of Kyrgyzstan travel for the kumis. Along the road, locals sell kumis from large, wood-framed tents known as yurts. A buyer can relax in a yurt while sipping.

Cows’ milk can also be used to make kumis. But kumis lovers say it’s not as good.

Why? God graciously gave people fermentation to preserve food and promote healthy flora—or microbes—in the body.