For those curious about the path from cocoa bean to chocolate, take a look at this concsice breif overview.
Varitiety & Terroir
Quality chocolate begins by using cacao that's grown from a quality tree. Different varieties and cultivars within a species, as well as clones within a variety, will produce very different products.
There are 10 clusters or "varieties" of cacao, many with specific characteristics including flavour. Flavours contained within the fruit will affect the flavour of the seeds after fermentation. Different clones within a variety will have specific traits, including different metabolisms. These difference affects the degree of uptake of specific elements from the soil, which may have an effect on flavour.
The region or country of origin the cacao beans originate from is important to the marketing of fine chocolate today. There are consistent flavour qualities that cacao seeds from specific areas have, but there isn't enough research that directly links terroir to the final flavour of chocolate.
Although the terroir (climate, environment, soil, terrain, farming) has an obvious impact on the growth of the tree, how much this impacts the flavour of chocolate requires more research before making definite claims.
"Bulk" cacao is cacao that is often quite astringent and lacking in depth of flavour. About 75% of the world's cacao is bulk cacao, and leads to chocolate that, although may be tasty to many, is often more simple in flavour profile than chocolate made of higher quality cacao. As well, more sugar is often needed to counter the astringency of bulk chocolate.
Cacao pods take 5-6 months to mature. There are two main harvests, but cacao trees will grow pods throughout the year. Pods which are harvested during the main harvests are said to be most flavourful. The pods contain the cacao seeds (AKA cacao beans) which are surrounded by a white fleshy fruit. The fruit and seeds are scooped out together and sent to the fermentation facility.
Some cacao growers will delay opening the pods for a few days or so. This reduces the acidification of the nib (cacao seed kernel) and is said to increase the cocoa flavour.
Ripe cacao pods don't usually fall off on their own, and are carefully hand picked from the trees one by one.
The fermentation process allows molds, yeasts, lactic acid bacteria, and acetic acid bacteria to grow within the fruit which covers the cacao seeds. These organisms will reconfigure the molecular structure within the kernel of the cocoa seed. Temperatures reach about 45 degrees celsius within the fermenting mass.
The carbohydrates and proteins will break down into reducing sugars and amino acids. Fermentation also kills the germ (AKA embryo) so that the seed does not germinate. It prepares the seed for the roasting process later on. This step essentially builds the precursor molecules that later on will interact to form the chocolate flavour!
Cacao that is not fermented properly (not long enough, too long, not warm enough) will produce off flavours, many of which will be very difficult to fix later on. Cacao growers and chocolate makers often work closely together to ensure the fermentation process allows for the qualities the chocolate makers are looking for.
Once the cacao seeds are finished fermenting, they are either laid out in the sun or dried with forced air and heat. Drying will occur over a few days. However, drying too slowly may cause unfavorable molds to impart off flavours into the seeds, and may ruin that entire batch.
Drying too quickly locks in much of the acidic aromas that were created during fermentation, making it more difficult later on for the chocolate maker to reduce the acidity in his chocolate.
In Southeast Asia and Oceania, the climate is often too wet to sun dry, and so wood burning ovens may be used with chutes that allow the heat to travel under drying shelves. However, the smoke from the ovens often seep into the beans, causing them to have a smokey flavour that ends up in the chocolate as well.
Once the seeds are dried, they are packed and shipped to chocolate makers. However, cacao beans are susceptible to absorbing odours along the way, and so care needs to be taken to keep humidity low and avoid the growth of mold.
Sort & Clean
Once the beans arrive to the chocolate maker, they need to be sorted. Because the cacao beans were often laid out in the open, they are exposed to environmental elements, debris, and animals.
Debris such as nails, rocks, feathers, mouldy or deformed seeds, coffee beans and even a rubber ball can end up in a sac of cacao seeds. These need to be removed by hand before proceeding.
This is often a concern for many when it comes to raw chocolate. Raw chocolate is made from cacao seeds that are not heated at a high enough temperature to kill off potential harmful organisms or elements that may make us ill.
Now the seeds begin to smell and taste like chocolate! The intense chocolate flavour is there thanks to previous stages of proper harvesting, fermenting, and drying.
They are roasted somewhere in the region of 15-20 minutes, depending on the characteristics of the seeds. The amino acids and reducing sugars created during fermentation, mary together over the heat to form hundreds of flavour compounds, most of which still have not yet been identified by chemists. Pyrazines, a group of aroma molecules, are formed here, and are the most important and most numerous aromas found in chocolate. This also dries out the cacao bean reducing the level of moisture to almost nil, which will be important during the next steps.
Makers who use lower quality beans, which are often more astringent, will also often over roast their beans to mask or cook off the off flavours of their beans.
Winnowing is an ancient method of removing the husks or casings from around the kernel of different seeds and grains. The fragile roasted seeds are crushed The kernel (or "cocoa nib") and husks are mixed together. Then, air is blown or a vacuum is used to remove the paper light husks from the heavier nibs.
The husks are a waste product, but can be used by some as mulch, to infuse into beer, or even make a tisane.
The nibs go on to make chocolate! The removal process of the husks also releases acidic aroma molecules held within the husk.
GrinD & Conche
Cacao used to be ground by hand using a metate usually placed over a small burning flame to warm up and melt the cacao nibs.
Today, machines are used to grind up the cocoa nibs (kernels of the cacao seed) into a paste, first on their own, then with sugar (and powdered milk if milk chocolate is being made).
Many small scale chocolate makers today use a melanger, two stone rollers that grind the ingredients into chocolate. These are the same machines which are used to grind spices. These melangers can still produce wonderful chocolate, but the flavour profile and texture are more difficult to control.
Other makers use two separate machines, a grinder of some sort (roll refiner) and a conche. A conche is a machine that further develops the flavour of the cacao. It allows the harsh volatile aromas, especially the acidic ones, to evaporate, leaving behind the more favorable aromas such as cherry, plum, or toast.
However, over conching will turn the chocolate quite bland, as not only will the harsh aromas evaporate, but the favorable ones as well. This is one reason why chocolate sold in supermarkets hold one flavour, chocolate. They often conche it longer to make up for the fact that they used astringent over roasted cocoa beans. Chocolate made by craft and artisan makers is often more vibrant, tasting like chocolate yet with additional notes such as cherry, plum, toast, and even hazelnut.
After the conche or melanger, the chocolate is poured into blocks and allowed to rest for a few months or so, according to the makers preference.
As the chocolate rests, the flavours mellow out and allow for the chocolate to reach its desired flavour profile.
Cocoa butter, the fat from the cocoa seed, is the component of chocolate that allows it to stay solid and room temperature and melt into a liquid just below our body temperature.
It's a polymorphic fat, meaning it can crystallize into 6 polymorphs, each with their own properties and melting points. Chocolate is generally tempered by warming it to above 45 degrees Celsius to melt out all the cocoa butter crystals. Then it is quickly cooled down to around 29 degrees, then back up to a working temperature of about 31-32 degrees Celsius. This allows for the development of the 5th and most stable polymorph, beta five.
A quality temper is one that allows for the chocolate to produce a smooth, shiny, single shade of brown surface. It will snap when broken, and melt just below body temperature. It's also at its optimal state for tasting!
Chocolate that is not tempered properly or has gone out of temper due to heat from improper storage, will lead to a whitish, mottled and less vibrant chocolate bar. It is still edible, but will not have the same metling or even tasting properties when eaten as a solid. For eating purposes, this can be fixed by melting it and enjoying it as a liquid!
The pride and joy of any chocolate maker. You can get an idea now of the amount of work that goes into making a chocolate bar. It's much more involved than grinding up some cacao beans with sugar and expecting it to taste delicious.
Remember, these cacao beans are grown in countries far from where they are exported to. Once they arrive to the manufacturing facility, they go through many steps in order to become chocolate. This is a highly processed food. Not in the negative way "highly processed" is used today in regards to nutrition, but highly processed as a tertiary food product.
Some may be put off by the cost of fine and craft chocolate in the market today, costing anywhere from $6 - $14 a bar. However, if you think of the amount of manual labour that goes into making them, it's more amazing that other makers can sell their chocolate for $1-$3 a bar and still make a hefty profit.
That said, a high costing bar doesn't distinguish it as high quality or tasty, but you do often get what you are paying for. The better you understand quality, the better you'll be at discerning it.