The flavour of chocolate explained

Photo credit: Galina Sanaeva

Understanding the process of chocolate will help you understand which aspects are important to building the flavour of chocolate.  Great tasting chocolate is the end product of all these steps being dealt properly.  Failure to do so will lead to a chocolate that may not be dynamic and satisfying, for which quality chocolate surely is.  

Chocolate flavour is determined by:


  1. Variety of cacao

  2. Environment

  3. Growth & harvest

  4. Fermentation

  5. Drying & storing seeds

  6. Roasting

  7. Other ingredients

  8. Conching or grinding

  9. Aging

  10. Tempering

  11. Packaging & storing chocolate



The Variety Cacao

There are many varieties of the Theobroma cacao. The main ones you hear about are criollo, trinitario, and forastero. There are also other varieties such as nacional, amelonado, porcelana, some of which are varieties within one of the first three already mentioned. Criollo cacao only makes up 1-3% of the chocolate made in the world, and researches state that no pure criollo even exists anymore. It's very aromatic, flavourful, and not very bitter or astringent. Forastero is much more robust, bitter, and not as aromatic. Chocolate made with criollo will generally be less bitter, and have more subtle aromas found within it. Trinitario is a hybrid of criollo and forastero, makes up 10-15% of the world's chocolate, and is also considered an aromatic and flavourful cacao leading to flavourful chocolate.  Most of the artisan chocolate sold today is made with a cacao that is hybridized between different varieties, with a focus on final aroma and flavour of the cacao bean.  Chocolate that is mass produced tends to be made with verities that contain less favourable aromas, and ends up being processed in a way that is less dimensional and flat as far as flavour is concerned. 



The soil and the climate greatly affect the makeup of the cacao seeds. Depending on where the trees are grown and what minerals are in the soil, the same variety grown in different regions can produce cacao seeds with very different aromas.  *However* There is little evidence that links the flavour of the cacao bean to the geomorphology (terrain, climate, soil) of where it grew.  This is often called terroir, the term used in regards to wine.  Terroir is important to the growth of the cacao, and has a definite impact on how the tree grows, the nutrients taken up, and the quality of the pods.  What that has to do with flavour is still being researched and debated. 

Batches of cacao from the same region may taste different due to the climate and environment changes from year to year.  This idea of terroir is associated already with wine and coffee, but is also being applied to chocolate as well. Many artisan bars will highlight the origin of the cacao beans, which will give the chocolate eater an idea of what flavours to expect.  Chocolate made with beans from Madagascar tend to be more tart than chocolate made with beans from Bolivia, which tend to have more nutty and toasted flavour notes.  Sometimes, like coffee and wine, regions may be marketed as better than others, which may push the price of a chocolate bar up depending on its regions.  However, where the cacao grows only part of the final flavour and quality.  Chocolate made from beans grown in Madagascar can be of high and low quality.  A region may affect the volatile aromas likely to occur in the beans, but not the quality itself. However, that said, there are regions that grow varieties (as mentioned above) that are less favourable.  Those regions are generally not associated with high quality cacao, not because of the region, but because of the variety of cacao grown.   


Growth & Harvest

How the growers propagate and harvest their cacao impacts the final flavour. Choosing to propagate trees that produce aromatic cacao as opposed to trees that produce bigger pods and seeds, and harvesting them during their optimal ripeness will also ensure good tasting seeds. Being careful to open the pods, not to cut into the seeds or delay their arrival to the next stage, fermentation, will also maintain optimal quality of the seeds.  Optimal growth and harvest will depend on how much resources the growers have, as well as their level of skill and education on growing cacao.



Fermentation is crucial to the flavour development of cacao. During fermentation, the seeds, still covered with the flesh of the fruit, are carefully allowed to ferment from 2-7 days depending on the variety of cacao. The fruit decomposes, and molds, yeasts, and bacteria are encouraged to grow. They in turn develop the aroma, flavour, and colour of the seeds. The cacao seeds themselves don't ferment, but are affected by the fermentation of the fruit surrounding them. The molecular makeup of the seed itself changes, allowing for the development of molecules that are the flavour precursors to the chocolate flavour that will develop in later processes.

Fermentation is very important in building the flavour of the final product that growers become very skilled in this area.  If the fermentation is not carried out properly or according to the standards required, this will affect the quality of the beans and what they can be sold for, which affects their livelihood and has a great impact on their future as a cacao grower.  Many growers have been growing and fermenting cacao for many generations, while others are quite new and still learning.  When chocolate makers seek out quality beans in different regions of the world, working with the growers on how they want them fermented can be a challenge on both sides.  Growers take pride in their process, while manufacturers may be very specific with what flavours they are trying to achieve.  Changing procedures in order to change the flavour of the beans is something both parties need to work on together.  This is one reason some artisan bean-to-bar makers have a direct relationship with the growers themselves.  


Drying & Storing Seeds

Once the seeds have been fermented, they are laid out to dry, either in the sun or heated underneath from a burning fire. Drying also is important in developing the flavour. Timing is important, since cacao that is dried to slowly is susceptible to mould. However, quickly drying the beans doesn't allow for the flavours to develop properly, and may also trap more acidity aromas within the bean. Climates where rain is an issue, care needs to be taken to cover seeds before showers, or at night to prevent dew from developing on the seeds.

Seeds are normally stored in burlap sacks, which allow for odours to pass through. Cacao seeds need to be stored away from strong odours, as well as from high humidity or temperature drops that may allow for the growth of moulds.



Roasting builds the final flavour of cacao bean.  Depending on the variety of beans, the origin, season of the harvest, and what the chocolate maker is trying to achieve, roasting times may vary.  Those precursor molecules developed during fermentation are transformed into the aroma and flavour of what we know as chocolate.  If the flavours during fermentation were not optimal, roasting will likely not help the desired flavour to be achieved.


The Maillard reaction also occurs between the proteins and sugars within the cacao bean, building on the flavour precursors to give us a bean with a more desirable taste. Roasting above 120 degrees Celsius also kills all the bacteria.


Other Ingredients

The type of sugar, milk powder, and flavours added to chocolate will also determine the final flavour. When they are added also determines flavour. Some milk chocolate is made by combining liquid milk with cocoa bean and sugar, and dried together. This allows for the Maillard reaction to occur, which requires proteins and sugars in the presence of water under heat to occur. Milk chocolate made this way tends to have more baked or caramel-like flavours. Adding more cocoa butter or ingredients that change how the chocolate melts in your mouth will also affect how we taste the flavours within it. Too little sugar in the chocolate, such as chocolate above 80% cacao, is quite astringent and makes it difficult for us to pick up more underlying delicate flavours. Too much sugar masks much of the flavours, and again, makes it difficult to pick up certain aromas.


Grinding (milling) and Conching

Grinding breaks the cocoa bean into finer particles.  Conching is a process that further reduces the particle size, but also fine tunes the flavour. During the process of conching, the acidic and harsh volatiles (aroma molecules) evaporate from the chocolate due to the movement and heat produced from friction within the machine. This mellows out the flavour, leaving behind the more desirable and delicate flavour that the acidity and astringency tends to mask. However, favourable volatiles are also evaporated during this process, and if conched for too long, even the favourable aromas will evaporate, leaving behind a very bland or less aromatic chocolate.  



After the chocolate reaches what the manufacturer feels is optimal flavour, it is allowed to set in blocks, and the blocks of freshly made chocolate are aged in a room void of strong odours and kept cool and dry. The aging further develops the flavour, mellows it out, and each manufacturer prefers different times for aging their chocolate, but usually at least a few months.



Tempering is the process of forming the cocoa butter in chocolate into the 5th (V) polymorph form. This form of crystallization gives the chocolate the properties most desired. These properties include a dark, uniform brown colour, shiny, hard, and with a good snap if broken. Chocolate not in this form tends to be mottled, whitish, brittle, and or dull. Tempered chocolate not only looks and feels pleasant, but the flavours within chocolate are best received by us when it is in its tempered form. Tempered chocolate melts just below body temperature, allowing the fats and aromas to escape over our tongue and into our nasal cavity and be taken in by our receptors. Untempered chocolate doesn't taste as pleasant, doesn't melt as nicely, and is not considered proper form for eating chocolate.


Packaging & Storing Chocolate

Once chocolate is properly tempered, it is best eaten within 6 months to a year. Chocolate contains tannins and is high in fat, which means bacteria can't survive or grow in it, and so can last for years. However, the flavours dissipate over time. Eating a chocolate bar 6 months after it was made or 2 years later will result in very different tastes. The flavours that were enjoyed from the 6 month old chocolate have muted or disappeared altogether from the 2 year old chocolate from the same bar or batch. Chocolate is best kept in a cold, dry environment, sealed well, away from other strong odours, and not for over a year.


Final Comments

It's not an easy task to answer what is good chocolate, as you can see there are many aspects that affect the taste and quality of chocolate.  The more consumers are educated on how chocolate is made and how it affects the final product, the more push there will be for makers to seek out optimal processes to achieve better tasting chocolate.  The blind spot consumers have on the process of chocolate allows many manufacturers to create mediocre chocolate and sell it as something it is not.  Being an informed consumer will allow you to discern what is quality chocolate, and the value you place on it will encourage those doing a great job making chocolate to continue.