Talk:Coffee extraction

Espresso extraction retracted
Only a few months after posting the original website, Jim Schulman retracted his comments on puck depth here: http://www.home-barista.com/tips/dosing-and-solids-extraction-retraction-t4752.html 3 years before this page was created.

I am not outright removing it because I may have missed another update, but I cannot see a more recent source for the information. — Preceding unsigned comment added by TheKrimsonChin (talk • contribs) 11:36, 17 April 2014 (UTC)

22% extraction and bitterness.
Added "In certain situations, yields surpassing 22% can be absent of bitterness.[6]" to clarify the prior statement on bitterness. Higher-grade equipment can extract certain coffees past this limit without bitterness. — Preceding unsigned comment added by Marzipandoll (talk • contribs) 06:59, 13 April 2016 (UTC)

Caffeine extraction
Many sources give the mass fraction of caffeine in coffee beans, but hardly anywhere can I find a source that explicitly says that the entire mass fraction of caffeine is extracted in brewed coffee. Many references, such as this one, say that the caffeine (whatever fraction) is extracted early.

I guess the implication is that if the extraction process tapers off to zilch before the brewing process has completed, well it must be all gone.

But isn't true in tea, so far as I've seen, where some of the caffeine is captive to the plant tissue.

The questions remains unaddressed whether coffee beans have any quantity of captive caffeine, such that the extracted value would differ from the contained value, even once the brew process has slammed into its extraction ceiling.

Sure would be nice to have at least one source that doesn't dodge this issue by neglect. &mdash; MaxEnt 17:53, 14 July 2018 (UTC)

This needs a reference because as it's written, it's saying the opposite of what's written in the following websites: https://www.home-barista.com/tips/what-variables-determine-caffeine-content-of-extraction-t54079-10.html https://www.caffevergnano.com/en/blog/is-there-more-caffeine-in-short-or-long-coffee