A litre of bilona ghee takes about 30 litres of cow milk, because a litre of ghee holds a little over 900 grams of butterfat and cow milk is only around four per cent fat. Churning curd also leaves some of that fat in the buttermilk. The trade is aroma: fermentation creates flavour compounds that the more efficient cream-separator route never develops.
People are often surprised by how much milk goes into a small jar of bilona ghee, and by how that shows up in the price. The number is not a marketing figure. It falls out of simple arithmetic about fat, plus one honest inefficiency in the traditional method, and it is the single most useful question you can put to any ghee brand.
At a glance
- Cow milk from Indian indigenous breeds is around four per cent fat, about 40 grams in a litre; ghee is at least 99.5 per cent milk fat under FSSAI's standard.
- Gathering the 900-odd grams of fat in a litre of ghee therefore needs more than 20 litres of cow milk even if every gram were recovered.
- Curd-churning leaves part of the fat in the buttermilk, so bilona ghee comes out at about 30 litres per litre; a cream separator recovers nearly all of it, at 20 to 23 litres.
- That is roughly a third more milk for the same jar, and milk is the largest cost in ghee by a wide margin.
- The return is aroma from fermentation and slow browning, not a different fat: the fatty acids follow the milk, not the method.
How much fat is in milk, and how much is in ghee?
Around four per cent in cow milk from indigenous Indian breeds, about 80 per cent in butter, and at least 99.5 per cent in ghee. Those three numbers set everything else: a litre of ghee is almost entirely fat, and a litre of milk holds only about 40 grams of it, so one has to be concentrated out of many of the other.
| Material | Fat content | Fat per litre or kilo |
|---|---|---|
| Cow milk (typical Indian indigenous breeds) | Around 4 per cent | About 40 grams per litre |
| Butter | Around 80 per cent | About 800 grams per kilo |
| Ghee | At least 99.5 per cent (FSSAI) | A little over 900 grams per litre |
Divide one by the other and you get the floor. To gather roughly 900 grams of fat from milk at around 40 grams a litre, you need a little over 20 litres of milk, and that is with every gram recovered, which no method achieves. Everything above that floor is the cost of the particular method. The 900-gram figure comes from ghee's density, which we work through in how much a litre of ghee weighs.
Buffalo milk is richer, at around six to seven per cent fat, which is why ghee made from buffalo or mixed milk can come out of fewer litres. Comparing milk-to-ghee ratios only makes sense between ghees from the same kind of milk; cow ghee vs buffalo ghee sets the two side by side.
Where does the rest of the fat go?
Into the buttermilk. The bilona method sets whole milk into curd overnight, then churns the curd until butter gathers into lumps that can be lifted out. Churning is effective, but not complete: a share of the fat stays suspended in the buttermilk as small globules that never join the butter.
A cream separator works differently. It is a centrifuge that spins fresh milk and pulls nearly all the fat out as cream in one pass. That is exactly what it was engineered to do, and it does it far more efficiently than a wooden churn spun back and forth by hand, which is the tool described in what a bilona is.
| Route | How the fat is gathered | Cow milk per litre of ghee |
|---|---|---|
| Curd-churned (bilona) | Whole milk cultured to curd, then churned to butter | About 30 litres |
| Cream-separated | Fresh milk centrifuged to cream, then made into butter or ghee | About 20 to 23 litres |
So bilona needs roughly a third more milk than the cream route for the same jar. The buttermilk is not wasted, since it is drunk, cooked with and sold, but its fat does not become ghee. The two routes are compared from start to finish in bilona ghee vs cream ghee.
What does curd-churning give back for the loss?
Flavour, in three ways: the aroma compounds that lactic bacteria make while the milk sets into curd, the nutty notes that come from browning the milk solids slowly, and the grain that forms when the ghee cools slowly. If bilona were only less efficient, nobody would still do it.
- Fermentation aroma. Setting milk into curd lets lactic bacteria work on it for hours. They produce aroma compounds, diacetyl chief among them, that give cultured butter its distinctive buttery, slightly tangy note. Cream-route ghee never goes through this step.
- Gentle browning. Clarifying slowly over a low wood fire lets the milk solids brown gradually before they are strained off. That browning is where most of ghee's nutty flavour comes from, and rushing it at high heat gives a flatter taste.
- Grain. Slow cooling after clarification lets fat crystals form larger and more irregular, which is the grainy, danedar texture many people look for.
What curd-churning does not change is the fat itself. Its fatty acids follow the milk, which follows the animal's breed and diet. We describe each stage of our own process, from setting the curd to straining the ghee, on the bilona process page, and the home-kitchen version, with a yield table for small quantities of milk, in how to make bilona ghee at home.
Why does the milk-to-ghee ratio vary?
Because milk is not a standard product when it comes straight from grazing animals. Fat content moves with the season, the forage, the breed and the stage of each cow's lactation. Hill cattle such as Badri give only one to three litres a day, and their milk shifts with what is growing on the slopes, so the ratio moves a little from season to season rather than sitting at one number.
That variation is also why colour and aroma change between batches. A summer jar made from animals on fresh pasture is usually more golden than a winter jar. Neither is a defect; both are what grazed milk looks like, for the reasons in why ghee's colour changes with the season.
Is a higher milk ratio a sign of better ghee?
Not on its own. A higher ratio tells you the method was less efficient at gathering fat, which is consistent with genuine curd-churning. It does not tell you the milk was good, the animals were grazed, or the clarification was careful. A careless producer can churn curd badly and lose more fat than a careful one: a higher ratio and a worse ghee.
What the ratio is good for is spotting claims that cannot be true. A ghee described as bilona and made from cow milk cannot plausibly come out at 15 litres per litre, because there is not enough fat in 15 litres of cow milk to fill the jar. A figure of about 30 litres per litre is what honest curd-churning of cow milk looks like. Pair it with a batch-coded lab report and a clear answer about what the animals ate, and you have most of what matters.
How does the ratio show up in the price?
Milk is the largest single cost in ghee, by a wide margin. Take 30 litres per litre as the figure for curd-churned cow ghee, multiply it by whatever a producer pays per litre, and then add overnight culturing, hand churning, hours of fuel, a glass jar, per-batch testing and shipping. When the milk comes from hill farmers paid above the bulk dairy rate, which is the point of sourcing this way, the floor is high.
That is also why the ratio is one of the best questions to ask any ghee brand. It is hard to answer dishonestly, because it sets a minimum price, and prices are public. A bilona claim at a commodity price means one of the two numbers is wrong. We walk through the full cost stack, with an illustrative milk rate, in how to judge a fair A2 ghee price.
The short version
A litre of ghee needs a little over 900 grams of butterfat, cow milk carries about 40 grams a litre, and churning curd leaves some fat behind in the buttermilk. That is why bilona ghee takes about 30 litres of milk per litre, roughly a third more than the cream route. The return is aroma and flavour you can smell as soon as the jar is open, not a different fat. You can see ours, with the current batch report, on the A2 bilona ghee page.
Sources
Further reading behind the figures above. Himdhara's own numbers — yields, batch results — come from our production records and the batch reports on the lab reports page.
- U.S. Department of Agriculture, FoodData Central (2019). Butter, clarified butter (ghee). FoodData Central (SR Legacy).
- Food Safety and Standards Authority of India. Food Safety and Standards (Food Products Standards and Food Additives) Regulations, Chapter 2.1: Dairy products and analogues (2.1.8, milk fat products). FSSAI.
- (2024). Genome-wide association studies of milk composition traits in indicine Badri cattle. Tropical Animal Health and Production.
- (2024). Genetic diversity, population structure analysis and codon substitutions of indicine Badri cattle using ddRAD sequencing. 3 Biotech.