Cacao percentages and aromas developed in chocolate from different origins About chocolate:

I tasted a 66% cocoa chocolate bar origin of Caribbean coast. And then, I tasted a 66% cocoa chocolate origin of Alpaco (Ecuador).

The only thing I've noticed it, that the Ecuadorian was stronger. The cacao taste last for long minutes in my mouth. But the Caraiban one, was subtle and delight.

The both have the same cocoa percentages. 

On the manufacturer site they wrote:


  This "Mariage de Grands Crus" from a small plantation along the
  Caribbean Sea has an exceptionally long nose and the soft aromas of
  nuts on the palate. CARAÏBE 66% is a perfect balance of smooth
  chocolate and roasted dried fruit notes with a slight oaky finish. Its
  opulent and soft, melody unveils subtle almond and roasted coffee
  flavors.


And:


  A Grand Cru whose subtle floral aromas melt exquisitely into supremely
  intense chocolatey notes. The majority of the cocoa used for ALPACO
  66% comes from the Ecuadorian Arriba bean. It combines strength and
  sophistication, and offers delicate floral aromas of jasmine and
  orange blossom, intimately and intricately intertwined with deep cocoa
  notes. The subtleness of floral aromas exquisitely melting into
  supremely intense chocolaty notes. Pure Ecuador.


How could I improve my tasting skills. I couldn't taste the orange blossom and jasmine aromas from the Alpaco. How chefs knows that a cacao has nutty or dried fruit notices ? And how just by changing the planting soil and environment will produce the same nibs but with different aromas ?

After all, if a meat cut coming from Australia, will taste the same as the one coming from America right ??
The cocoa plants/grains were grown in different areas, the soil they grow in will have different mineral content; the heat and humidity will be different, the plant will grow in different ways resulting in cocoa pods and grains will be different.

They will have different flavors, sometime it is subtle, sometimes it is obvious.

This is what people, in mostly wine countries, call terroir.

The only way to train yourself tasting chocolate is to taste more and more chocolate and taking notes. 

The most difficult thing when tasting is to find the proper words; sometime you will taste of smell something subtle, but you cannot make the connection with the actual corresponding word.

You will smell something that smell like nutmeg, but your brain is not trained enough to make the connection.

You can find Wine Aroma kits containing small vials of "flavors" that you can use to train your nose. This can be used even for chocolate, just as a training tool.

(Anecdotal) I'm part of a wine tasting group, most of the other attendants are translators, writers, and they are better than I am in finding words corresponding to what they smell and taste.