Why does dark chocolate taste so bitter?
Contrary to what most people believe, not all dark chocolate is bitter. Dark chocolate is not synonymous with bitterness. But how can this be? Some of you might think to yourself, all the dark chocolate I have ever tasted is bitter. On behalf of the chocolate industry, I would like to apologize for this experience!
There are a few points that might help you understand the idea of bitter dark chocolate.
Bitter tasting components of cacao beans
The alkaloids and polyphenols in cacao bean are generally bitter in taste. The bitterness of seeds like those of cacao are to deter herbivores and frugivore from consuming the seeds. These bitter components, however, are also some of the beneficial components such as antioxidants. Although the trees want to produce bitter seeds, humans on the other hand prefer seeds that are less bitter. This brings us to the next point.
The quality of the cacao (Which Dictates Quality Of The Chocolate)
Image by Bean To Bar World.
The reason most of the dark chocolate in the world tastes bitter has to do with the cacao bean used to manufacture it. The there is a range of quality when it comes to dark chocolate. Many, including myself, for simplicity reasons state chocolate is either poor quality commercial chocolate or high quality fine chocolate. The truth is, there is actually a range. This range is based on multiple factors, but the main one is the quality of the cacao bean used. Poor quality cacao can only lead to poor or mediocre quality chocolate. Roughly 80% of the world’s cacao grown today can be deemed “poor”, “bulk”, or “commercial” quality cacao. This cacao tends to have higher levels of bitterness, and less range in other aromas beyond the aroma of “cocoa”.
Nearly all the chocolate in the word is made with bulk or lower quality cacao beans. This is your standard commercial cacao used to produce chocolate made by enormous and large scale chocolate manufacturers (Hershey, Nestle, Lindt, Mars, Cadbury, Callebaut, Cacao Barry, and many other less known brands). Much of the variance between these brands might be the grade of the cacao, but also the way in which the cacao is processed into chocolate by that specific manufacturer.
A high quality cacao will lead to a high quality chocolate (low to no bitterness, and a more complex range of aromas). For instance, the 70% dark Gran Blanco bar by Qantu has zero bitterness, and tastes sweeter than your average 70% dark chocolate bar. One might even assume it’s a 60-65% bar. Compare this to a commercial 70% bar, and it will have obvious bitter notes. Even if going up to 85%, a high quality bar can still have no bitter taste, where a commercial bar will always be bitter at that percentage.
The bitterness in chocolate comes from the quantity and types of polyphenols within that specific bean used to make that chocolate. Bitterness is a property of many alkaloids (think coffee or black tea). Some cacao beans have high levels of bitterness, some have low levels, or in some cases have no bitterness in them after they are fermented and roasted. There are even some unroasted cacao beans that can have no bitterness due to selective breeding. The genetics dictates to a degree the level of bitterness, but so does the process of how the cacao beans are fermented, cured, roasted, and processed into chocolate.
Bitterness for the cacao tree is good. It means animals and humans will not want to consume the seed, so that the seed can grow into a tree. Over Millenia, humans have selected for cacao trees to produce seeds which are less bitter. In regards to chocolate, this is a great thing. The only problem is, most of the world has not consumed dark chocolate made from this type of high quality cacao bean.
The Bitter Receptors
From Handbook of Olfaction and Gustation by Richard L. Doty.
How an individual receives the bitterness also depends on what’s in their mouth, receptor wise. There are differences between us in regards to the quantity and types of bitter receptors in our mouth. There are 25 functional human genes associated with bitter receptors, and they can vary from person to person.
There is a bitter compound known as propylthiouracil (PROP), which is not detected by every individual to the same degree. There are those who can detect the bitterness of PROP and individuals who cannot, depending on if they have genes for this receptor turned on or not. Of those who can detect the bitterness of PROP, some detect it moderately, and some detect the bitterness as extremely bitter (compared to the sensation of breaking your bones).
This difference between those who can detect it is also genetic. This is just one of many variations individuals have when it comes to bitterness detection and tolerance in our foods.
The reason your child may hate that broccoli could be because they detest it as much as you might hate the feeling of breaking a bone!
How we detect bitterness may also have an impact on what we consume, which can alter our behaviour surrounding our health and nutrition. It’s possible that those who do not detect PROP at all also may have a higher body weight, sometimes consume more alcohol, and tend to consume more fatty sugary foods. Those who detect PROP as extremely detestable also seem to dislike vegetables and be thinner. PROP sensitivity is also associated with grater taste sensitivity overall (but don’t confuse this with aroma or flavour sensitivity).
Plasticity of Bitterness detection
Just like plasticine can be reshaped, so can our thresholds and tolerance for bitterness. Image by Vika Wendish
Bitterness, just like any tastant (sweet, salty, sour) are plastic and our thresholds of them can change over time, and not just in one direction. When we are born, these tastants are set at standards according to what is helpful to our development (sweet = good, bitter = bad). However, as an adult, you can learn to change your tolerance level to a degree.
In fact, if your mother always cooked with lots of salt, chances are you have a high tolerance for it, and require more than you need for food to be deemed tasty. If you learned to enjoy the bitterness of dark chocolate (for whatever reason I will never understand haha) you can in the same way force yourself to tolerate sweeter chocolate, and your threshold will change. If you go a month or two of eating sweet milk chocolate (and other sweet foods), even after years of eating bitter dark chocolate (or low sugar foods), when you go back to consuming dark chocolate, it will taste even more bitter or intense than you remember. However, after months of lowering your sugar intake and consumer low-sugar foods, you will be back to enjoying your high-percentage dark chocolate again without thinking it tastes bitter.
conclusion
The bottom line is, although many of us grew up equating dark chocolate to bitterness, this isn’t actually the case for all chocolate. One reason is perhaps we enjoyed sweeter foods and chocolate growing up. The other reason is all the chocolate we consumed was made with poor quality cacao, and so tasting 70% or 80% dark chocolate instilled in us memories and emotions of detest.
The truth is, one can taste a 75% high quality dark chocolate bar that is not bitter, and also taste a 65% low quality dark chocolate bar that tastes even more bitter than the 75%, even though it has less sugar. This is because although sugar can decrease the bitterness of our chocolate (as salt can decrease some bitterness as well), it can only mask it to a degree. Once a poor quality chocolate has more than 65% cacao more or less, the bitterness will be very evident. This is not true for a true high quality dark chocolate.