The percentage on a chocolate wrapper is the most trusted piece of information about the product. But what exactly it measures is generally not known.
What does the percentage state?
The cocoa percentage is the share of components derived from cocoa in the product.
It covers two components.
The first is cocoa mass, the ground cocoa bean.
That contains both cocoa solids and the natural cocoa butter.
The second is added cocoa butter.
A figure of 70 percent says that 70 percent of the product by weight consists of those two components.
The remaining 30 percent is generally sugar with a little emulsifier and vanilla.
But the distribution within that percentage does not get stated; all the confusion arises from there.
Why do cocoa mass and cocoa butter differ?
The two components carry entirely different properties.
Cocoa solids provide the chocolate's bitterness, colour and aroma.
The flavanols sit in that part; the health claims originate there too.
Cocoa butter is a neutral fat.
It is nearly tasteless and without aroma.
It determines the melting behaviour and the texture in the mouth.
Two products at the same percentage can therefore be weighted toward solids in one case and toward butter in the other, and their tastes differ greatly.
| Product | Cocoa | Cocoa solids | Cocoa butter | Sugar |
|---|---|---|---|---|
| Brand A dark | 70% | ~42% | ~28% | ~29% |
| Brand B dark | 70% | ~30% | ~40% | ~29% |
| Milk chocolate | 35% | ~15% | ~20% | ~45% |
| White chocolate | 30% | 0% | ~30% | ~45% |
| Cocoa powder | 100% | ~80% | ~20% | 0% |
Why does the same percentage give different products?
The table shows that difference.
Both dark chocolates contain 70 percent cocoa.
But the cocoa solids run 42 percent in one and 30 in the other.
The product higher in solids is more bitter and more intensely aromatic.
The one higher in butter is softer and melts more easily.
Their sugar is the same but the experience of taste is entirely different.
That difference does not appear on the label.
But it registers immediately in tasting; the butter-weighted product feels creamier on the palate while the solids-weighted one feels drier and sharper.
How is the sugar calculated?
That is the most useful side of the percentage.
Knowing the cocoa percentage allows the sugar to be estimated.
Sugar can be at most 30 percent in a chocolate at 70 percent cocoa.
In practice 28 or 29; the remainder is emulsifier and vanilla.
Sugar can be at most 15 percent in a product at 85 percent cocoa.
It can reach 48 percent in one at 50 percent cocoa.
That calculation explains why cocoa percentage gets used as an indicator of health; high cocoa means low sugar, and that relationship is direct.
How strong is the link with bitterness?
Bitterness rises as the cocoa percentage rises.
But the relationship is not linear.
Bitterness comes from the polyphenols in the cocoa solids.
Cocoa butter carries no bitterness.
A 70 percent product weighted toward cocoa butter can therefore taste less bitter than a 60 percent one weighted toward solids.
The origin of the bean and the degree of roasting matter too.
Beans from some regions are naturally less bitter.
Long roasting at high temperature reduces the polyphenols and lowers the bitterness, but it also simplifies the aroma.
How valid are the health claims?
The health claims about chocolate originate in flavanols.
Those compounds sit in the cocoa solids.
They have antioxidant effects.
Some research reports favourable effects on blood pressure and vascular health.
But the quantity of flavanols needed for those effects is high.
Roasting and alkalisation also markedly reduce flavanols.
Alkalised cocoa — the Dutch process — gives a darker colour while its flavanol content halves.
A high cocoa percentage is therefore not a sufficient indicator on its own; the processing method decides at least as much.
What else gets checked on the label?
Four things get checked alongside the percentage.
The first is the order of ingredients. Cocoa mass should come first; where sugar comes first the product is dominated by sugar.
The second is added fat. Where palm oil or vegetable fat appears the product is not true chocolate.
Up to 5 percent vegetable fat is legally permitted, but it markedly changes the texture and taste.
The third is a declaration of cocoa solids. Some producers state that separately; that is the most transparent approach.
The fourth is milk powder; its presence in a dark chocolate shows the product is not truly dark.
Which percentage suits what?
The choice varies with the purpose.
Sixty to seventy-five percent is balanced for eating directly.
Bitterness is acceptable and sugar low in that range.
Above 85 percent is very bitter and requires a trained palate.
Fifty-five to sixty-five percent gets used in pastry; balance comes from the sugar added in the recipe.
Sixty to seventy percent suits ganache and coating.
Above 70 percent gets preferred in hot chocolate; because milk brings sweetness and softness, a high cocoa percentage balances it there and the drink does not stay one-dimensional.
What does the percentage change in baking?
The figure directly affects the balance of a recipe.
Chocolate high in cocoa carries less sugar and more solids.
That thickens a mixture.
Using 75 percent in place of 55 in the same recipe leaves the result drier and more bitter.
Compensation goes in two directions.
The first is sugar; 5 to 8 percent more goes into the recipe.
The second is liquid; ten to twenty millilitres of milk or cream joins it.
The ratio is more delicate in ganache; one measure of cream suits chocolate at 70 percent and half a measure at 55, and ignoring that difference leaves the ganache either running or setting hard as stone.
