Think Ive tried everything, still making sour coffee..

[coffeedave]

Hi all,

Ive owned a Sunbeam EM6910 for about 7 months. Up until now, I havent had time to get into the end to end method of brewing a good coffee... Ive also just been using pre-ground coffee.

Ive recently completed a basic barrista course, thoroughly cleaned the machine (as per instructions) and got myself a grinder and some nice beans.. After numerous attempts at making a great cup, I have managed to improved the overall process, however I am continually making very sour coffee. Ive read forum advice on this and other sites, with no success as yet. Any assistance? Im starting to wonder if theres a problem with the machine itself. Cheers.

[blanyon]

Re: Think Ive tried everything, still making sour coffee..

Need more info, type of beans, time of pour, colour of pour, volume of shot, what sort of grinder (hopefully burr). Then we might be able to help.

[Koffee_Kosmo]

Re: Think Ive tried everything, still making sour coffee..

It may also be water temperature related
Brew water too hot or too cold can also give sour shots

KK

[coffeedave]

Re: Think Ive tried everything, still making sour coffee..

Need more info, type of beans, time of pour, colour of pour, volume of shot, what sort of grinder (hopefully burr). Then we might be able to help.

Thanks , Ill have to grab all the info tonight and post back then.
Cheers.

[coffeedave]

Re: Think Ive tried everything, still making sour coffee..

HI Coffeedave
I was in the same boat with my machine (BZ99) a few weeks ago.
To cut along story short, my cooling flush was too short, i didn`t get enough over temp water out. Now i do a longer cooling flush, put the handle straight in and pour. Apart from doing this all my other processes have been the same , and i haven`t had a sour cup since.
My tamping is still not consistent , but i have my grind fairly consistent when i change beans. I have been working on 1 thing every week since i fixed the sourness and now the coffees not perfect  coffee  but it is good to very good coffee every cup now - to my taste anyway.
hope this helps
Cheers
Jordan

Thanks Jordan, excuse the ignorance, I have to admit Im not sure how to extend out the cooling flush? Thanks for your help.

[cksyd]

Re: Think Ive tried everything, still making sour coffee..

Thanks Jordan, excuse the ignorance, I have to admit Im not sure how to extend out the cooling flush? Thanks for your help.

Coffeedave -

On a 6910 hit the manual button and let water come through into the tray for a few seconds before you lock the pf in place. Hit manual again to stop the flow, then load n lock.

Also, when you turn the machine on are you putting the pf and basket in the group head to warm it all up first?

Chris

[coffeedave]

Re: Think Ive tried everything, still making sour coffee..

Thanks Jordan, excuse the ignorance, I have to admit Im not sure how to extend out the cooling flush? Thanks for your help.

Coffeedave -

On a 6910 hit the manual button and let water come through into the tray for a few seconds before you lock the pf in place. Hit manual again to stop the flow, then load n lock.

Also, when you turn the machine on are you putting the pf and basket in the group head to warm it all up first?

Chris

Thanks Chris,
Ok, so I am doing this, and yes, I make sure I warm it up for at least 10-15 mins, typically turn it on earlier than this. Ill try extending the cooling flush. Cheers again.

[acoggins]

Re: Think Ive tried everything, still making sour coffee..

Pretty sure youll find that sour shots comes from either low temperature or under extracted shots. A cooling flush, if anything, is going to exacerbate the problem. On my 6910 I always hit the manual button for 2-3 seconds just to flush grinds off the showerhead, but not to cool.

Coffeedave, are you hitting the mark in terms of 25mls in 25-30 seconds? or is it running faster than this? Would you consider the crema quite blond? or is it a dark brown/reddish colour? If the shot is running fast and the colour is fairly blond, then youre probably underextracting the shot. Try for a finer grind to slow down the shot.

With the risk of overloading you with information and things to check, start with that for now.

[coffeedave]

Re: Think Ive tried everything, still making sour coffee..

Pretty sure youll find that sour shots comes from either low temperature or under extracted shots. A cooling flush, if anything, is going to exacerbate the problem. On my 6910 I always hit the manual button for 2-3 seconds just to flush grinds off the showerhead, but not to cool.

Coffeedave, are you hitting the mark in terms of 25mls in 25-30 seconds? or is it running faster than this? Would you consider the crema quite blond? or is it a dark brown/reddish colour? If the shot is running fast and the colour is fairly blond, then youre probably underextracting the shot. Try for a finer grind to slow down the shot.

With the risk of overloading you with information and things to check, start with that for now.

Cheers, I believe Im close to 25mls in 25 secs. Im still playing with the grind, so colour varies. The only thing that has taken some of the sourness away is not tamping too hard. As soon as I try for a firm tamp, I have problems with extraction, and/or a sour tasting coffee.
Ill have to get all of the facts this evening, and post them so as to at least provide a baseline.
Thanks very much.

[acoggins]

Re: Think Ive tried everything, still making sour coffee..

If youre getting 25 in 25 or thereabouts, then look at the pucks afterwards, check for any signs of chanelling, it usually looks like wormholes. Is the puck firm or sloshy?

I didnt see any mention of your grinder type either...

[Gavin1]

Re: Think Ive tried everything, still making sour coffee..

Channeling in your puck can also cause under extraction and sourness.

Distribute the coffee evenly before brewing.

[Justin_Boyle]

Re: Think Ive tried everything, still making sour coffee..

Cant you control the temp on 6910? If it is getting too hot when sitting idle then shouldnt you just turn down the brew temp?

[Thundergod]

Re: Think Ive tried everything, still making sour coffee..

Can we assume firstly that Dave hasnt previously fiddled with the temperature settings.
Ive used a 6900 and then a 6910 and had no need to adjust the temp on the 6910 as the taste of the coffee was never sour.

I am also going to assume that the dose and or grind size is the culprit from Daves mentioning that a hard tamp gives him "problems with extraction, and/or a sour tasting coffee".

Dave please elaborate on what you mean by "extraction problems".

When we find out details of your grinder it might be another clue.

I only ever flushed the 6910 as part of my cleanup routine, never as a cooling flush, as its not necessary.

Dave, we await more input.

[Dimal]

Re: Think Ive tried everything, still making sour coffee..

I only ever flushed the 6910 as part of my cleanup routine, never as a cooling flush, as its not necessary.

Or desirable...

With Thermoblock machines, flushing through the Group will far exceed the designed heating capacity of the t/block heating system and lead to cooling down the assembly which will result in brew water temperatures that are probably lower than ideal. This will lead to sour tasting shots.... :P

Mal.

[coffeedave]

Re: Think Ive tried everything, still making sour coffee..

Hi all, Thanks for your postst, Ive included some further information below;

Grinder: Café Series® Conical Burr Coffee Grinder EM0480
Beans: Ive tried a variety. Currently using Brazil, Fazenda Kaquend CoE#1 (too expensive, i know..)
Pour Time: ~30 secs
Colour: begins as a dark drip for 5-10 secs, then becomes a thicker browny-gold slow pour
Volume: ~30ml
Temperature settings: Ive maxed the steam temp, and reduce steam wetness, and left the brew temp as factory default, as recommended by a few people owning this model of machine.

Thanks again all.