If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.
Re: Pour speed changes with constant dose and grind.
Originally posted by 695D4A5C47706C4049494A4A2F0 link=1281312134/11#11 date=1281423297
To summarise:
a) different supply = different roaster = different blends of beans = different density of coffee = different amount of volatile oils = different amount of resistance in the puk = different rate of flow for a given amount of pressure.
b) different age of beans / grinds for the same blend = different amount of volatile oils = different rate of flow.
Which is why grinders are adjustable hehehe....so you can adjust down to slow the flow.
Volatile oils are not "real" oils...as the name infers they are volatile and go off into the atmosphere. The process of ageing / staling is the process of the volatiles going off into the atmosphere "piggy backing" on the CO2 gassing off. This means as the coffee ages, there is less oil in it = less resistance in the puk = quicker rate of flow.
All of this is normal for fresh coffee.
Stale coffee has effectively finished gassing off, has a much lower amount of volatile oils, & therefore has exhausted its beautiful aroma. But it is very "consistent" (there goes the C" word again) and requires much less adjusting of the grinder.....
But try explaining all that to the "I know better than you" espresso machine operators in cafes, that dont know how to adjust the grinder, and think that fresh coffee beans should be "consistent"
Hope this helps.
Regrdz,
Attilio
very first CS site sponsor.
Now that is a fancy of saying 2 + 2 = 5
AND it makes perfect sense to me except for the following;
Which is why grinders are adjustable hehehe....so you can adjust down to slow the flow.
LOL I thought ya just used a bigger tamper or used a bigger Barista to stomp on it ;D
(Joshing of course - my bitter antisocial side showing)
Re: Pour speed changes with constant dose and grind.
To summarise:
a) different supply = different roaster = different blends of beans & different methods of roasting using differing equipment and roasting profiles = different density of coffee = different amount of volatile oils = different amount of resistance in the puk = different rate of flow for a given amount of pressure.
b) different age of beans / grinds for the same blend = different amount of volatile oils = different rate of flow.
Which is why grinders are adjustable hehehe....so you can adjust down to slow the flow.
Volatile oils are not "real" oils...as the name infers they are volatile and go off into the atmosphere. The process of ageing / staling is the process of the volatiles going off into the atmosphere "piggy backing" on the CO2 gassing off. This means as the coffee ages, there is less oil in it = less resistance in the puk = quicker rate of flow.
All of this is normal for fresh coffee.
Stale coffee has effectively finished gassing off, has a much lower amount of volatile oils, & therefore has exhausted its beautiful aroma. But it is very "consistent" (there goes the C" word again) and requires much less adjusting of the grinder.....
But try explaining all that to the "I know better than you" espresso machine operators in cafes, that dont know how to adjust the grinder, and think that fresh coffee beans should be "consistent"
Hope this helps.
Regrdz,
Attilio
very first CS site sponsor.
Re: Pour speed changes with constant dose and grind.
Originally posted by 6C6165606D6A6373617770040 link=1281312134/3#3 date=1281392800
Do fresher beans pour faster or slower?
Which origins are slower and why?
Will higher moisture content speed up or slow the pour?
What about the roast level?
There is no general rule but some extreme examples are the Yemen BI that needs a fine grind and the Aussie MTE that needs a course one. Reasons are density and moisture. To be fair there is to many bean types out there and they all vary. Older beans generally need a slightly couser grind.
Apart from that you will just need to feed the Auto the freshest beans you can, dont leave more than you need in the hopper at anyone time (helps maintain freshness) and adjust the grind as needed to try and get a decent shot out of it.
Re: Pour speed changes with constant dose and grind.
Just to answer one of your questions best i can,
I have just started roasting my own and found that fresh beans (1-3 days old) do not seem to always pour faster or slower than older beans (1-2 weeks).
Ive had fresh beans that ive had to use very coarse setting and fresh beans that required very fine settings.
As AM said, there seems to be so many variables that i cannot say for sure if older or fresher pours slower or faster.
Re: Pour speed changes with constant dose and grind.
Originally posted by 737E7A7F72757C6C7E686F1B0 link=1281312134/3#3 date=1281392800
Thanks all for the answers. I was hoping for something a bit more detailed. I already know that many things affect the pour and require a grind adjustment, but what about specifics.
For example:
1: Do fresher beans pour faster or slower?
2: Which origins are slower and why?
3: Will higher moisture content speed up or slow the pour?
4: What about the roast level?
Has anyone had specific observations about these things?
You have not given enough exact SPECIFIC details... ;D
The issue is that there are 1001 variables -
1: Define fresher
2: Depends on how they were treated... And some behave very differenty to how you might have thought or what roaster was used...
3: Depends on what level of moisture and as to the beans them selves as well as the impact the moisture might have on the grinder....
Every thing you can think of; has variables that will affect the outcome. Your dealing with a raw product and a whole lot of equipment; that all do things differently. Further more, one little shift and it can have a significant impact on the cup 8-)
That is what you will fine many here saying the same thing; be it in a slightly different manner..
2 + 2 = 5 where 5 = great coffee
You can paint by number but you can not make coffee by numbers
Thus if your a black and white person who wants a pure formula spelt out ( no greys)... Not going to happen.
Any number of rules of the thumb; but again lots of variables that have to be considered and nut assumed.
Re: Pour speed changes with constant dose and grind.
Thanks all for the answers. I was hoping for something a bit more detailed. I already know that many things affect the pour and require a grind adjustment, but what about specifics.
For example:
Do fresher beans pour faster or slower?
Which origins are slower and why?
Will higher moisture content speed up or slow the pour?
What about the roast level?
Has anyone had specific observations about these things?
Re: Pour speed changes with constant dose and grind.
Originally posted by 3B3632373A3D3424362027530 link=1281312134/0#0 date=1281312134
automatic coffee machine
AND
Originally posted by 3E323B36363F530 link=1281312134/1#1 date=1281312806
Hi Heading west
lots of things change the pour just a few would be
freshness, type of bean / blend, time of bay, humidity, roast depth (colour), storage used, even depends on your rate of use within the same bag of beans....
when you change beans expect to change the grind
Having just repaired two SUPER Autos... I love the marketing...
The beans actually grind into a pre dosing chamber; that what you do not have to wait as the grinds are always ready for use :
Same as for manual dosers.. If ya fill it and then dont use it - the grinds will be stale..
headingwest - Do some more reading as to Bean management.
Supermarket beans are not always fresh..
Rough guide as to a best before with correct storage:
Green Beans / Unroasted best B 4 3 years
Roasted Beans best B 4 3 weeks (kept in valve sealed bag)
Ground Beans best B 4 3 min
So if ya changing beans and or from different suppliers and you may or may not have had a coffee or 3 for a while ..... Then you have to take all that into account.. As well as the Quality of the grinder...
Then; I guess you leave the fresh beans in the bean hopper and top up every couple of days it means ya back to Stale beans...
This is why; Great coffee is almost imposable to find and Good coffee hard to find; while average / poor is the norm
Or is it that being a CS has raised the bar too high :-/ :-/ :-/ :-/
Re: Pour speed changes with constant dose and grind.
Hi Heading west
lots of things change the pour just a few would be
freshness, type of bean / blend, time of bay, humidity, roast depth (colour), storage used, even depends on your rate of use within the same bag of beans....
I have an automatic coffee machine. When I change to different beans from a different roaster the pour speed can change dramatically, even stopping the flow.
I know that the grind and dose are constant, so what is it about the beans that changes the flow rate??
Leave a comment: