Dosing, Grinding and Extraction Lenght; variables inter-linked

[oneday]

Hi guys,

quick query here for the commercial baristas;

if your coffee is tasting (for e.g) a little unclean, what would you do the dose, grind and extraction length to improve the taste? secondly, why?

cheers

[A_M]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

Hi guys,

quick query here for the commercial baristas;

if your coffee is tasting (for e.g) a little unclean, what would you do the dose, grind and extraction length to improve the taste? secondly, why?

cheers

What do you mean unclean ??

You forgot about changing the temp / pressure.. Depending on your equipment type..

OR

BEANS

When trying to work out tastes / flavours etc... Unless you have a trained pallet and others are on the same page.. You can end up chasing ya tail..

http://www.home-barista.com/naked-extraction.html

[luca]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

Depends what you mean by "unclean". If you mean that it tastes like the machine is dirty, surely the answer is to clean it.

If by "unclean" you mean more towards an ashy or bitter, then Id probably go for some combination of coarse grind/high dose to speed up the flow rate and/or probably lower the brew temperature. The reason is, of course, based on taste. I find that higher brew temperatures can bring out bitterness. Coarser grind and higher dose gives you the greatest resistance that you can get from overextraction, as you have a lot of coffee from which proportionally less is being extracted. However, this is not like a ristretto; youre keeping the flow rate fast to keep some acidity in there and keep it balanced.

All of that said, there are limits to what you can do and those limits are set by the quality of the coffee to start off with and by its roasting. If the "unclean" taste that you are talking about is due to a mould defect in the green or baggy green, for example, then you cant get rid of it. If the "unclean" taste is because the coffee is roasted too dark or stale, then all that you can do is to mitigate it. Remember that quality is created at origin; in consuming countries; roasters and baristas can only recognise and reveal it.

Sometimes, unfortunately, theres not much that you can do about it. I walked a friends family through using a new multi-boiler PID machine at their cafe a few weeks ago and, unfortunately, it seemed as though the blend that they had had been created from multiple singles roasted separately and, so, was a blend of over and under-roasted coffee. This meant that everything was a catch 22. For example, increasing the temperature decreased the sourness, but it increased the ashyness. Decreasing the temperature had the opposite effect.

Cheers,
Luca

[oneday]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

what i was referring to was taste on the palate; if the coffee was not tasting its best then what steps would you implement regarding dose and grind to clean up the taste?

I simply said unclean as an example, you could replace that adjective with too acidic or too bitter. I guess i am just trying to work out how the variables of dose and grind will influence the cup served. Consider the machine to be clean, and pressure to be 9bar.

thanks luca for the advice thus far,

j

[TC]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

what i was referring to was taste on the palate; if the coffee was not tasting its best then what steps would you implement regarding dose and grind to clean up the taste?

Hmm...Its so unspecific a question as to be pretty much impossible to answer...:
[*]Clean the machine and grinder[*]Get some training to improve your skills or find someone who has the required slills to make your coffee for you...[*]Ditch the coffee and get some fresh, expertly roasted stuff

2mcm

[WSullivan]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

what sort of gear are ya using, that will give us an indication of what variables you are able to tweak, eg dual boiler, HX or single boiler......PID? etc, every bean is different, and ive found for some a fine grind and light tamp produces what i want, other will require a courser grind and a harder tamp, then there is under/overdosing blar blar blar, the list of variables is long, as AM will say 2 + 2 = 5......so so true in espresso!

we would like to help, ya just need to set the scene.........

[oneday]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

The query is merely hypothetical, with the aim of trying to establish connections between variables that will be useful to the cafe barista, analagous to the likes of increased humidity to result in a coarser grind

Perhaps that is no guideline or formula, or that the formula is constantly getting rewritten!

But I would like to be in a position where I could manipulate controllable variables to produce (or hide!) a desired profile in the cup, so that if one day the coffee was tasting slightly too acidic, I would (for eg) increase the dose and opt for a coarser grind.

[TC]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

Hmm....

Im just heading off to commence my 100000 word thesis entitled:

"Coffee and the variables which influence extraction"

Back in 5...:  ;D

Alternately, purchase and read a copy of The Professional Baristas Handbook- by Scott Rao

[hazchem]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

to me, THIS is where the fun and tinkering with espresso lies. Constantly asking what happens if I change dose and grind? What will the impact be to this coffee on this day? Can I make it better? Can I make it worse to find what is better?

Eventually, if you have consistently roasted coffee I expect that you will hit on a series of parameters/variables and changes to them that will bring predictable results. But I would expect youd have to work with the same coffee, day in, day out under a variety of environmental conditions to establish what they are.

Speaking for myself, each time I step up to Miss Silvia, I expect that something will be different. Will I like it? Maybe not, but then the cycle begins over again to find that combination of parameters that works for the coffee I want to drink at that time.

I dont think you can expect to lock this down to a simple formula easily or quickly.

Im just heading off to commence my 100000 word thesis

sheesh, ONLY 100000 words 2MCM? I reckon you could be a student for life trying to finish that one.

[Luke_G]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

Im not sure if many of you guys picked it up but his name is startingfromscratch ?

From what i can gather he is attempting to understand what can be done about dirty tasting coffee using grind and dose techniques.

The answer?... not much.
Sour, bitter, burnt, acidic and ashy are tastes that can be eliminated if they are due to extraction. But dirtiness is only related to the beans them self or the machinery. If its the machines boiler or water pipes, under side of baskets, heads, shower screens, inner group handles or even the spouts or water used for extracting, then its likely fixable.
If its the bean its self then the only thing you could do it throw some sugar at it? lol

Dirtiness is often related to poorly processed, aged, monsoon dried, robusta, or fermented coffees. Sometimes its a nice jammy dirtyness but other times its just plain yuk!
But most often it will be stale coffee that tastes dirty...still a little bit like coffee but just undesirable.

Good luck startingfromscratch. Sounds like your interested enough to listen

[oneday]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

As stated below, the query was merely hypothetical!

[A_M]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

As stated below, the query was merely hypothetical!

In fact while you may be proposing a hypothetical (above) it is what every one has to deal with every day..

you could replace that adjective with too acidic or too bitter.

Even here with what may sound simple.. There are so many variables as both terms are very different.. Worse still is that many will state it was Bitter when it was Acidic and some will even use teh term sour.. Yet they all have different causes.

Thus my links on understand extractions..

As with out knowing your equipment and raw products.. The cause could be one of many..

As 2mcm said let me go and do my thesis .. ROFLMAO. Only 100000 words... Must be part 1 of 3 ;D

That is why I state that 2 + 2 = 5 for good coffee... As it depends on teh size of the 2s...

If making good coffee was as simple as a maths formula.. Then Auto would rule the world..

Put it another way.. Its like saying " my car sound funny" or "my PC is running slow"..

With out lots of background it could be any thing..From the wheels, drive chain, gearbox, motor etc etc.. Oh in this case it was a heavy duty plastic bag caught between teh front grill and cooling system... Only played up as certain speeds and thus many got caught looking at the harmonics etc. Yet the sound was described as flapping..

Thus - if a bird shits in the backyard do you look for a common sparrow or a rare eagle ?

When coffee that was good starts tasting like crap.. What are the simple things that would change.. Look there, rather than at the fine detail of the machine.

With new coffee.. (one assumes it is OK).. Then ya methods need to be reviewed.. Temp / tamp / grind / time / temp etc etc

However in all cases.. A clean and well maintained machine is a SHALL... So many do not clean their group heads often enough.

[bjeck14]

Re: Dosing, Grinding and Extraction Lenght; variables inter-linked

to me, THIS is where the fun and tinkering with espresso lies. Constantly asking what happens if I change dose and grind? What will the impact be to this coffee on this day? Can I make it better? Can I make it worse to find what is better?

Aaaaaaammmeennn. Coffee is a wonderful combination of art and science, and the never-ending desire to achieve the god-shot keeps us striving to improve our understanding of how these variables effect what happens every morning