an intuitive guide to coffee solubles, extraction and tds - 2

picture 1

water is here to save the day! when water enters the coffee cells it begins dissolving the solubles. this new solution of solubles dissolved in water is known as coffee. 

picture 2

not all solubles are created equal (picture 1 and 2 ).



when we look at the total mass of a coffee bean, only 30% of it consists of solubles. the other 70% of the bean is made of insoluble fibers and carbohydrates that create the beans structure.

pictures 3

about 20% of the bean contains good solubles and the other 10% are bad and taste awful. to brew the best cup of coffee we have to try and release the good solubles while leaving the bad ones locked up in the cells ( picture 2 ).

luckily the bad solubles move slower and take longer to dissolve than the good solubles so we can coordinate the jailbreak by limiting amount of time water has to work.

the longer water is in a cell, the more solubles are extracted

in the coffee world, extraction rate is the term used to quantify how many of the solubles should remain locked up in the coffea arabica prision cell and how many we want to free.

the optimal guidelines set by the scaa for extraction are 18 - 22%. so this means that when we take the total weight of our coffee beans, 18-22% of that mass will be dissolved by water and end up in our cup.