A quaker is an industry term to describe under-ripe, undeveloped coffee seeds that fail to roast properly.
These are most often the result of unripe coffee cherry making it into the final product. Normally, these are removed in hand selection during harvesting, by the coffee pulper (in the wet-process), or visually removed in the dry-process method. They can be removed on the density table at the dry mill in some cases as well.
They occur much more often in dry-process coffees due to the fact the coffee is not run through a pulper machine, which can be pretty effective at removing green unripe coffee cherry. Even the best coffees might have occasional quakers, and they can be removed post-roast when they are easy to see.
Under-developed coffees do not have the compounds to have a proper browning reaction in the roaster (Maillard Reaction), so they remain pale in color. What’s with the name? Is it derogatory? Not exactly… My own theory on the term: Quakers are those resist fighting in war? Right? Quaker beans are those that resist roasting in the drum! Coffee roasting re-imagined as war? hmmm…
