Cocoa content in a chocolate refers to the total percentage of the ingredients that come from the cocoa bean. This includes the cocoa liquor or cocoa mass made from grinding up cocoa nib, plus any added cocoa butter.
One of the most common misconceptions in chocolate is that 70% is a magic number, that somehow chocolate above 70% is magically better for you or that chocolates above 70% are automatically bitter. Despite what you’ve read or heard ...
There is zero direct correlation between cocoa content and healthiness or bitterness or any other qualitative assessment of a chocolate.
Percentage is a quantitative measure, so the only thing you know when you know the cocoa content of a chocolate is about how much sugar there is, and even then the correlation can be loose.
With a typical two- or three-ingredient dark chocolate bar (cocoa beans/mass/liquor, sugar, cocoa butter) the percentage will tell you how much sugar is in the chocolate. That’s all. Generally, chocolate makers don’t (and many small chocolate makers often can’t) disclose how much of the cocoa content of their chocolate is the non-fat solids – what we think of as cocoa powder – and what percentage is fat (cocoa butter). The only way to figure this out is if there is nutrition facts label. You have to take a look at the total number of calories from fat in a serving and the size of the serving to calculate the ratio. And it's likely an approximation or average.
When you start adding in other ingredients – vanilla, lecithin, milk, etc. – the cocoa content all on its own reveals even less. In a 33% cocoa content milk chocolate, the other 67% is split (mostly) between sugar and milk. Again, you have to go to the nutrition label and take a look at the added sugars entry to calculate the sugar content, and even that’s an approximation because of the lactose (milk sugar) in the recipe.
A good way to think about cocoa content is to compare it with alcohol proof.
Which is better, an 80-proof vodka or an 86-proof vodka? The answer is there's no way to know just from the number. The proof does not tell you anything about the quality of ingredients used or the care with which the vodka was made and it certainly doesn’t tell you anything about the taste of the vodka. All you really know is how much water there is. In an 80-proof vodka, 60% is water.
The only reason an 86-proof vodka is automatically better than an 80-proof vodka is if it's the same price or less expensive and your sole reason for drinking is to get drunk.
Similarly, cocoa content tells you nothing about the variety used to make the chocolate, if the trees were healthy and the seeds were at their best when the pods were harvested, the care taken during fermentation and drying, and how the beans were roasted and the chocolate conched, to name just a few of the steps that go into determining the flavor of a finished chocolate.
Cocoa content tells you none of that. One really good example of how confusing this can be is Zotter’s 80/20 dark milk chocolate. It’s 80% cocoa content, but the 20% is milk – there is zero added sugar other than what’s in the milk. Plus, different sugars have different levels of sweetness so the same recipe made with different sugars will likely taste very differently. And some sweeteners, such as coconut blossom sugar, have distinctive flavor profiles of their own.
- There is no direct connection between cocoa percentage and bitterness. An 80% cocoa-content chocolate is not necessarily more bitter than one at 70%. Much depends on bean variety, fermentation, and roast level.
- There is no direct connection between cocoa percentage and healthiness. A 70% cocoa-content chocolate is not necessarily healthier than one at 60%. A lot hinges on bean variety, fermentation, and roast level. But it is necessary to factor the sugar into the equation.
- There is no direct connection between cocoa percentage and taste. Everything depends on bean variety, origin, fermentation and drying, roast level, type of sugar used, and the effects of other manufacturing steps. Changing of those parameters while keeping the percentage the same will result in a chocolate that tastes different. Often very different.