Philobiblon

From Stuff Matters, by Mark Miodownik
p. 92-3
“Cocoa trees grow in tropical climates and produce fruit in the form of large, fleshy coca pods. These look like some form of wild and leathery orange or purple melon. The pods grow directly out of the trunk of the tree … inside each pod are 30 to 40 soft, white, fat almond-shaped seeds the size of small plums. … we harvested the cocoa beans using machetes, and then deposited them in a heap on the ground, where we left them to rot. This is how all chocolate is made. Over two weeks the heaps of beans start to decompose and ferment, and in the process they heat up. This serves the purpose of ‘killing’ the cocoa seeds, inasmuch as it stops them from germinating into cocoa plants.But more importanty it chemically transforms the raw ingredients of the cocoa beans into the precursors of the chocolate flavours…. fruity ester molecules are created, the result of a reaction between the alcohols and the acides that are created by enzymes acting within the cocoa beans… the taste of chocolate is highly dependent not just on the ripeness and species of the cocoa bean, but also on how high the rotting piles of beans are stacked, how long they are left to rot and generally what the weather is like.”

p.94-5
Drying and roasting … ” roasting turns the bean into a mini chemical factory,… first, the carbohydrates within the bean, which are mostly sugar and starch molecules, start to fall apart because of the heat. This is essentially the same thing that happens if you heat sugar in a pan: it caramelises. Only in this case the caramelizing reaction takes place inside the cocoa bean, turning it from white to brown, and cretaing a wonderful range of nutty caramel flavour molecules…. Another type of reaction, … also contributes to the colour and flavour of the cocoa: the Malliard reaction. This is when a sugar reacts with a protein …. reacting ith the acids and esters and resulting in a huge range of smaller flavour molecules. It is no exageration to say that without the Maillard reaction the world would be a much less delicious place: it is the Maillard reaction that is responsible for the flaour of bread crust, roasted vegetables, and many other roasted, savoury flavours. In this case the Maillard reaction is responsible for the nutty, meaty flabours of chocolate, while also reducing some of the astringency and bitterness…

Grind up the fermented and roasted cocoa nuts and add them to hot water and you have the original hot ‘chocoatl’ made by the Mesoamericans… When Europeans explorers got hold of the drink… they exported it to coffee houses, where it competed with tea and coffee to be the beverage of choice of Europeans – and lost. What no one had really mentioned was that ‘chocatl means ‘bitter water’ and even though it was sweetened with the new cheap sugar … it was also a gritty, oily and heavy drink, because 50% of the cocoa bean is cocoa fat. This is how it remained for another 200 years, an exotic drink, notable but not terribly popular.”