The magic that happens when turning green coffee to brown

Raw coffee is green. Roasted coffee is brown.

Sure, we all know that!

But what you may not know is the magic that happens behind the scenes when green coffee turns brown, which awakens the wonderful aromas and flavours we all know and love.

There are a number of chemical reactions that turn coffee from green to brown when you apply heat to dried, raw green beans.

Firstly, there’s caramelisation

Sugar plus heat equals delicious, sweet caramel. During roasting, caramelisation occurs as heat breaks down starches and changes them to simple sugars. This changes the colour of the bean along with it’s flavour and aroma.

Also during roasting, at around 200 degrees celsius, oils develop such as caffeol. This is the oil that makes coffee smell like coffee.

Secondly, there’s the Maillard reaction

Named after French chemist Louis-Camille Maillard, this is the same reason why steak and bread turn brown when cooked. Essentially it’s a chemical reaction between amino acids and sugars and further draws out delicious, natural flavours and aromas. Apparently over 500 new taste compounds are created through the Maillard reaction.

The magic bringing it all together

Then magic occurs somewhere in the marriage of the flavours imparted by nature, which are concentrated during fermentation and processing, combined with the flavours and aromas drawn out through roasting. The result is that we are gifted with a  beautiful, full-flavoured, aromatic, super complex beverage. Apparently coffee boasts four times the complexity found in red wine!

This is the magic when green beans turn brown.

Drink it daily, savour it, and keep it special!

One comment

  1. Thanks for the most interesting article. Your Xmas roast was the best ever. We enjoyed it immensly. Keep up the good work. We have enjoyed watching your progress over the last ten years. Jeanette and Ron.

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