Post By GrahamK
Can roast affecting flow rate.
Quick question. The last few days my coffee has been flowing too fast. (double shot in 15secs.)
My grind stayed the same,dose and my tamp pressure would be the same also.
Only thing that has changed is the roast time of my most recent beans.
Ive tried grinding finer without and real influence.i even increased the dose to see if it affected anything
Roast depth, beans types, age of roasted beans, storage method, humidity....etc. could all be factors. Adjusting the grind will probably be the most relevant change you will need to make to suit the circumstance I believe. However you mentioned that you have already tried that. It may be useful to list what equipment you are using for someone to provide more guidance.
using a Gaggia classic. Em440 grinder. beans were the last of my Colombian beans order from the bean bay. the same problem was happening with the work set up.
well i tend to think that i have eliminated the variables enough to boil it down to a fairly simple question of "can roast profile influence flow?"
the only real change was the roast time of this batch. increase up to 15 mins
Originally Posted by cloudwarrior
As already brought to your attention by GrahamK, roast depth (one aspect of a roast profile) is one of many variables that can affect flow rates. Generally speaking, a longer roast profile yields beans with relatively lower moisture content. These drier beans offer less resistance to the flow. Having said that, this is still only one variable that may be affecting your rate of flow. Don't dismiss bean age, humidity, temperature, etc..., etc...
In any event, no matter the cause, adjusting the grind and/or dose will get you back into the sweet spot without too much trouble. Constant tweaking is the norm when it comes to the pursuit of the perfect cup.
i have come to grips with the slight adjusts as the beans age etc. but this last roast was right off the chart. just on feel of the grinds that were very sandy and dry and couldn't get fine enough at all
appreciate the responses guys
Last edited by cloudwarrior; 12th June 2014 at 08:19 PM.
Let's not forget that roast profile probably also influences the physical structure of the beans and chemical composition of the extractable fraction - which also has a strong influence on the flowrate.
Colloquially known as "drying out"
Originally Posted by MrJack
Colloquially known as"roasting"