A cheese pack says "minimum 45% fat in dry matter" while the nutrition table shows 22 grams of fat. Both figures are correct; they measure different things.
What is dry matter?
Everything remaining once the water is removed from a food is called dry matter.
In cheese, dry matter consists of protein, fat, minerals and a small amount of carbohydrate.
The water content of cheese varies widely by type. Fresh white cheese runs 55 to 60 percent water, aged kaşar 35 to 40.
Dry matter is the inverse: 40 to 45 percent in white cheese, 60 to 65 in aged kaşar.
That ratio can vary even between batches of the same cheese; as ripening continues, water falls and dry matter rises.
How is fat in dry matter calculated?
The formula is simple: the fat in the product divided by the dry matter.
With 22 grams of fat and 45 grams of dry matter per hundred grams, the calculation runs: 22 divided by 45, roughly 49 percent.
So "49% fat in dry matter" means the actual fat in the product is 22 percent.
The gap comes from the water content of the cheese.
In a high-moisture cheese that gap widens; in a low-moisture cheese it narrows.
Comparing two cheeses on fat in dry matter is therefore misleading when their water contents differ.
| Cheese | Water | Dry matter | Total fat | Fat in dry matter |
|---|---|---|---|---|
| Fresh white cheese | 58% | 42% | 19% | 45% |
| Ripened white cheese | 50% | 50% | 25% | 50% |
| Kaşar (young) | 42% | 58% | 27% | 47% |
| Aged kaşar | 36% | 64% | 32% | 50% |
| Curd cheese | 72% | 28% | 6% | 21% |
Why is this method used?
Because cheese loses water as it ripens.
A cheese may contain 20 percent fat on the day it is made; three months later the same cheese shows 28 percent because it has lost water.
No fat was added; only water left.
If classification used total fat, the same cheese would change class as it ripened.
Fat in dry matter stays constant. As water goes, both fat and dry matter concentrate at the same rate and the ratio does not move.
That is why the measure is used in cheese classification; it describes the production standard, not the fat on the plate.
How are cheese classes defined?
Classes are set by fat in dry matter, and the class appears on the label.
Full fat cheese: at least 45 percent fat in dry matter.
Semi-fat cheese: between 25 and 45 percent.
Low fat cheese: between 10 and 25 percent.
Fat-free cheese: below 10 percent.
The term "extra full fat" is also used and generally indicates above 60 percent.
These classes do not give the fat on the plate directly; the nutrition table is what to read.
Is milk different?
Milk is simpler, because its water content is treated as constant.
In milk the fat percentage is total fat directly. Milk at 3 percent contains 3 grams of fat per hundred millilitres.
Whole milk runs 3 to 3.8 percent.
Semi-skimmed runs 1.5 to 1.8.
Skimmed milk is below 0.5 percent.
In raw milk the fat varies with the animal, the season and the feed; in processed milk it is standardised.
That standardisation is done by separating the fat and adding a set proportion back.
How are butter and cream read?
Butter must contain at least 80 percent fat.
The remainder is water and milk solids. That also explains why butter releases water in the oven.
In clarified butter the water and milk solids are removed; the fat content exceeds 99 percent.
In cream the fat content determines the application.
Whipping cream requires at least 30 percent fat. Below that, cream will not hold foam.
Coffee cream runs 10 to 18 percent and does not whip.
Clotted cream can exceed 60 percent, which gives a structure you can take with a spoon.
How does fat affect texture?
In cheese, fat leaves gaps within the protein network and softens the texture.
Reduced-fat cheese is firmer and more rubbery; the protein network tightens.
Melting behaviour changes too. Fat provides lubrication during melting; fat-free cheese does not melt, it softens.
Flavour carrying depends on fat as well. Most aroma compounds are fat-soluble; with less fat the flavour flattens.
This is why salt is generally raised in reduced-fat cheeses; salt partly compensates for the lost flavour.
That compensation belongs in the assessment when looking at nutrition.
In what order should the label be read?
Three steps suffice when buying cheese.
Step one: read the fat per hundred grams from the nutrition table. That is the real quantity reaching the plate.
Step two: look at the fat in dry matter statement. That shows which class the product is in and how it was made.
Step three: check the salt. Cheese is the largest sodium source in many diets.
Use the same line consistently when comparing; reading fat in dry matter on one product and total fat on another produces a meaningless comparison.
Products using vegetable fat in place of milk fat cannot be called cheese; they are sold under a different name and can be identified from the label.
How does fat content affect price?
Milk fat is the most expensive component in cheesemaking and it drives the price directly.
The volume of milk needed for a kilogram of cheese rises with the fat content. In high-fat cheeses that can reach ten litres.
Fat also affects yield. Part of it passes into the whey; the quality of the method determines that loss.
Reduced-fat cheeses would be expected to cost less, but that is not always so. Those products need additional processing and ingredients to compensate for texture.
In cream and butter the price is almost directly proportional to fat; cream at 35 percent costs markedly more than at 18.
