Chhurpi cheese drying. Krish Dulal / wikimedia / 2011 / CC BY-SA 3.0
Chhurpi is a very hard, chewing cheese made in Tibet, Bhutan and Nepal. In Nepal, it is called either “chhuga chhurpi” or just “chhurpi.” In Bhutan, it is called “durukhowa” or “durukho.”
Chhurpi can be made from buttermilk, skim milk or whole milk from yaks or chauri (a cross between a cow and a yak). Whole milk is actually the least preferred, not only because the fat in the whole milk can be used for other dairy products, but also because whole milk yields a cheese that is softer and won’t store as well. An ideal milk mixture (expressed in more Western terms) would be approximately ⅞ skim milk, ⅛ half fat milk.
It can also be made from sewsew cheese.
The milk is heated to 60 – 65 C (140 to 149 F.) Fermented milk is added to the mixture, which is allowed to curdle while it cooks further. It is then strained, put into wooden moulds, and pressed with stones for 24 hours. It is then cut into small cheeses which are let dry for 12 to 15 days, or dried with smoke for 10 days.
The cheese ends up as hard as a piece of chalk.
The cheese can be chewed as a snack while travelling, or ground into a powder for use as a condiment in soups.
“Durukho: Milk solids produced by boiling mahi (buttermilk) are wrapped in a cloth and pressed under stones. When all the whey is driven out, the resulting mass is cut into one-inch cubes and dried in the sun. People like to chew the dry durukho when climbing in the Himalayas. It is also produced from partly skimmed milk.” — Food and Agriculture Organization. The technology of traditional milk products in developing countries. March 2011. ISBN 92-5-102899-0. p. 240.
It is a higher-value cheese because it stores better:
“Chhurpi has a longer shelf life and is considered to be of better
quality than churtsi (smoked cottage cheese) or serkam (soft fresh cottage cheese).” — Food and Agriculture Organization. The technology of traditional milk products in developing countries. March 2011. ISBN 92-5-102899-0. p. 59.
A market has also been found in the First World for selling chhurpi as dog chews.