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Cheese from Nepal, Bhutan, Tibet and the Indian Himalaya
Hard chhurpiछुर्पी
Buttermilk or skimmed milk left from butter-making is heated and soured until the casein curdles. The curd is pressed into a block, cut into strips, then smoked over the fire and dried for weeks until it is rock hard. It is chewed slowly, like gum.
Fully documentedCheese37 days
Recipe
Amounts from a sourceAn improved lab method from Nepal (Shrestha 2015). About 4 kg of chhurpi comes from 100 L of milk. The sources give no fixed traditional amounts.
Buttermilk (sweet-cream buttermilk in the study), or skimmed milk100 parts
All-buttermilk scored as well as all-skim-milk chhurpi[shrestha2015]
the milk is soured by back-slopping before churning (dahi); the curd is set by acid and heat
Total time across the recorded steps: 37 days
Start
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What changes:Soured milk is churned and the butter is lifted off the buttermilk
Step 1 of 7
Sour the milk and churn out the butter
Time
Not documented
Temperature
Not documented
Salt
None given
Acidity
Not documented
Which microbes the steps name, step by step
Lactic acid bacteria
Lactobacillus helveticus
Lactococcus lactis
Lactobacilli
Output: crude butter (gheu or mar) and buttermilk.
Flavour
sour
Texture
Not documented
Colour
Not documented
Microbes at work in this step
lactic bacteria sour the milk (dahi), which is churned for butter
Method
Measured measured in a studySet fixed by a specification or tested recipeReported one source reports itTypical a general value, not sourced for this fermentUnconfirmed not yet checked against a source
At a glance
Buttermilk or skimmed milk left from butter-making is heated and soured until the casein curdles. The curd is pressed into a block, cut into strips, then smoked over the fire and dried for weeks until it is rock hard. It is chewed slowly, like gum. Made in 7 steps over 37 days. The longest step, dry in the air and sun, takes 30 days (Shrestha S.R 2015). Lactobacillus helveticus and Lactococcus lactis do most of the fermenting.
Hard chhurpi is soft chhurpi taken further. The pressed curd is cut, smoked and dried until it is rock hard, while soft chhurpi is eaten moist in curries and soups. Unlike Mongolian aaruul, it is made from buttermilk left after butter-making and is dried over a fire.
pH
Churkam: pH 5.71–5.74 for Arunachal cow (11 samples), 5.82–5.87 for Arunachal yak (3 samples), 6.34 for one North Sikkim sample
Soft chhurpiThe curd is not smoked and dried hard; it is eaten moist in curries and soups, with rice, or as a momo filling. It is the most common form in Bhutan.
Safety
Pressed curd holds at least about 55 % moisture, so it must be dried promptly to stop mould and bacteria from spoiling it. Drying improves the keeping quality; smoking adds flavour. The dry product takes up moisture easily, and Nepalese producers store hard chhurpi at 8–10 °C. A study of Nepalese exporters says it is common for chhurpi to grow mould on long transport.
Panta and colleagues write that chhurpi making goes back a thousand years in the remote Himalaya. Trade in Nepalese chhurpi as a dog chew began after 2003; exporters reported shipping 15.65 tonnes in 2019/20, up from 8.5 tonnes the year before.