keno wrote:It's the other way around, grinding coarser will increase the flow, reduce shot time, underextract, and accentuate sour flavors. On the other hand, grinding finer will slow the flow, increase shot time, increase extraction, and accentuate more bitter flavors. Are you perhaps adjusting your grind incorrectly?

If your are grinding too fine and getting 22g dose 22g out in say 30 seconds , then that will be nominally under extracted , the strength may hide the sourness though ..

True, but I was making the assumption that the brew ratio remains the same - in which case a finer grind will get you your target weight more slowly than a coarser grind or, to keep the time the same, the dose will need to be smaller for the finer grind.

keno wrote:It's the other way around, grinding coarser will increase the flow, reduce shot time, underextract, and accentuate sour flavors. On the other hand, grinding finer will slow the flow, increase shot time, increase extraction, and accentuate more bitter flavors. Are you perhaps adjusting your grind incorrectly?

Hi, what you said is true, but when you grind too fine and use too much coffee, water won't be able to penetrate thru the puck thus extracting some percentage of the coffee in the portafilter. This point is known, im some parts, as the "point of diminishing returns".

Thanks.

Mrboots2u wrote:have you cupped or brewed the beans ? Are they more balanced in the cup then , if so id be adjusting your recipe , perhaps 44-46g . Although these are now big espresso's are they for large milk drinks? You could save some cash going to 19-20g adjusting the grind , adjusting the recipe to 40-44 g , perhaps even getting a sweeter brew into the bargain

I've tried to brew my espressos with lower doses but since the temperature and the humidity in my city are way too high the coffee suffers from degass way too fast thus making me compensate the loss with more coffee. Would love to get good espressos with 20 grams but after a couple of days I start to obtain acid espressos.

A 20 gram dose is, in my opinion, closer to a triple than a double. See what happens when you grind finer and use a dose in the 14-16 range. You have a Mythos One, so your equipment is more than up to the task. Doubles are typically more forgiving and the cafe standard, not least because most people can just generally get better tasting shots with doubles.

If you're concerned about overly quick expiration due to your climate conditions, then perhaps try to keep your coffee orders more on pace with your consumption, if it's possible? Just my two cents.