HomeRoast Digest


Topic: Sour espresso taste (19 msgs / 933 lines)
1) From: Mike Wilkens
Does anyone have hints on temperature surfing the Gaggia Classic?  I saw the earlier posts from 2006 on this subject, tried what was detailed there, didn't work for me.
My shots are very consistent in taste, problem is they're all extremely sour tasting.  I've used four different beans, two different grinders, two different espresso machines (New Baby and Classic).  To raise the brew temp, I draw water (PF off) until the heating element goes on, install PF, wait until heating element goes on, wait 6 s, and pull.
Unless I'm preparing it with coffee, the PF is installed at all times.  30 minutes warm up.
Also tried turning on steam switch for 10 seconds just before pulling the shot, all other parts of surfing ritual the same.  No difference.  Coffee temp in the cup was 168*F +- 2*F.
Of course I've also tried just walking up to the machine and pulling.  No difference.
I've ground fine enough that 2 drops of coffee come through, but if I get coffee it's extremely sour tasting.
To my untrained eye, the crema usually appears tan and not chocolatey brown, which I'm told signifies underextraction.  Also to my untrained eye, the flow of the shot appears to go from dark dark brown straight to blond, without going through that reddish brown phase.  Suspecting channelling, I added another ritual sometimes called the Weiss Distribution Technique but could also be called Stirring with a Paperclip.  No difference.
Next step is to find a 6 year old child...
-Mike
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2) From: denis bordeleau
Hi Mike,    I'm only 5 but I'll try answering that one. I have a Ranc=
ilio Sylvia.        From what you said it appears you have 2 =
problems: sour taste and cold water in the cup.  Sour taste can be becaus=
e of rancid oil accumulation and minerals.  So, clean both of your machin=
e and decalcify them.  Temperature problem will  probably  be solved.=
  Check your chain of  T°. If you have steam ­in the wand and=
 168 degrees in the cup you have a loss in between. Keep your porta filte=
r hot and panty (not in the freezer), warm the cup and try bigger size th=
an ristretto.  Clean the grinders with instant  minute rice to get rid =
of sour tasting oil by cleaning the burrs.  Be sure the blend is OK by tr=
ying another extraction and grinding method.   For cleaning, backwash a=
nd decalcifying method on the Gaggia New Baby and Classic models, go with t=
he instructions book or the mighty list will come to your help.    I =
wish you good luck and a
 very nice evening
 =
 De : Mike Wilkens 
À : homeroast =
Envoyé le : samedi 2 juin 2012 2h36
Objet : [Homeroast] Sour espresso taste
  =
Does anyone have hints on temperature surfing the Gaggia Classic?  I saw =
the earlier posts from 2006 on this subject, tried what was detailed there,=
 didn't work for me.
My shots are very consistent in taste, problem is they're all extremely sou=
r tasting.  I've used four different beans, two different grinders, two d=
ifferent espresso machines (New Baby and Classic).  To raise the brew tem=
p, I draw water (PF off) until the heating element goes on, install PF, wai=
t until heating element goes on, wait 6 s, and pull.
Unless I'm preparing it with coffee, the PF is installed at all times.  3=
0 minutes warm up.
Also tried turning on steam switch for 10 seconds just before pulling the s=
hot, all other parts of surfing ritual the same.  No difference.  Coffe=
e temp in the cup was 168*F +- 2*F.
Of course I've also tried just walking up to the machine and pulling.  No=
 difference.
I've ground fine enough that 2 drops of coffee come through, but if I get c=
offee it's extremely sour tasting.
To my untrained eye, the crema usually appears tan and not chocolatey brown=
, which I'm told signifies underextraction.  Also to my untrained eye, th=
e flow of the shot appears to go from dark dark brown straight to blond, wi=
thout going through that reddish brown phase.  Suspecting channelling, I =
added another ritual sometimes called the Weiss Distribution Technique but =
could also be called Stirring with a Paperclip.  No difference.
Next step is to find a 6 year old child...
-Mike
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3) From: Paul Leung
Hi Mike,
I have a Gaggia Classic + Baratza Vario. Been enjoying great shots for 2+ years now after some tweaks. I would strongly encourage you to join the Gaggia users group on Yahoo! It is a great resource. You could have a faulty boiler thermostat. You can do a styrofoam cup temp check as described in the group's archive.  You may also want to consider installing a PID to better control temp and also adjust the OPV to 9 bar while you're at it. I've done both things and noticed a significant improvement in shot quality and shot consistency immediately with no need to change distribution, tamp, etc. techniques.  I used to do WDT- no real need to do so now. I also swapped out the stock steam wand with a Silvia v2 wand for improved steaming power and quality. There is also a bit of a pre-infusion trick that has made my shots sweeter and richer. Routine maintenance practices: daily H2O and weekly detergent backflushes, quarterly descaling (YMMV) help too. I always use SM homeroasted beans, of course.
I think the Classic can be a very capable machine with those minor mods. I usually just drink shots (milk drinks just for guests) and feel no need to upgrade to another machine for some time. I have been very pleased with the Vario as well.
Good luck!
Paul
Sent from my BlackBerry

4) From: Mike Wilkens
Hi Denis, those are all great suggestions.  Regarding temperature, I think 168*F coffee temperature measured in the cup is good or even on the high side.  This is measured after the water has gone through the coffee, and through the air, and into the warmed cup.  At the group showerhead the temperature is much higher.  I measured that too using imperfect methods.
I want to clarify the sour taste if I can.  It is not prickly or tacky, it is the "off" taste like sour milk -- but again, without the tackiness or metallic perception you might get from sour milk.
Your other suggestions are good, I've brewed in an Aeropress everything I've put in the machine, and they all taste pretty good to great.  The blends I've been using lately are Espresso Forte (Peet's) and Toscano (CCC).
My grinder is a used Mazzer Mini, and I've been told that worn burrs can cause a sour taste, and to install new burrs.  I'm doing that next, we'll see if that has an effect.
Regarding cleaning: is minute rice more effective than manual cleaning?  I've been using a toothbrush & vacuum cleaner to get gunk off there.  I'm sure there are oils left after my cleaning though.  I don't taste bitter or rancid in my AP brews...
I should've decalcified & cleaned out the New Baby more throughly (I only took off the showerhead), but the Classic is brand new.
It seems like you covered all the bases.  There's channelling, which is supposed to be another possible cause of underextraction.  At this point I believe I'm preparing the puck fairly well.  We'll see what the new burrs do.
-Mike
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5) From: Larry Dorman
Does the yahoo list allow users to sell their used gaggia machines?
LarryD
On Jun 5, 2012 1:34 PM, "Paul Leung"  wrote:
<Snip>
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6) From: denis bordeleau
Hi Mike,      Thanks for the come back.  We all appreciate. =
   The test with the AeroPress might be  unconclusive at 50% becaus=
e of the paper filter that retains the coffee oily elements. Also, try =
a manual or other grinder if you have one. Put Instant Minute Rice in the M=
azzer Mini with the old burrs inside  and try again an alternate brewing =
method without paper filter.  Unscrew the brewgroup filter and gasket of =
both the Baby and Classic Gaggia and compare them. May be "Brand New" meant=
 an open box or a demo.  Use citric acid and vinegar at that moment.  C=
heck the brew group filter holes and clean with the small provided needle t=
ool if necessary.  Be sure you use the double cup Portafilter size and =
that this filter is not clogged due to your  too fine grindings and too h=
eavy Weiss technic tampering in the past that caused channelling and it=
 will confirm that your problems and effort to resolve them are not fixin=
g the original
 problems but only the symptoms that are now showing.  We don't all die=
 because we are born; that's probably due to something in between or vice-v=
ersa.  Keep on and you will enjoy the cup you deserve.      D=
enis 
 =
 De : Mike Wilkens 
À : homeroast =
Envoyé le : mardi 5 juin 2012 15h19
Objet : Re: [Homeroast] Sour espresso taste
  =
Hi Denis, those are all great suggestions.  Regarding temperature, I thin=
k 168*F coffee temperature measured in the cup is good or even on the high =
side.  This is measured after the water has gone through the coffee, and =
through the air, and into the warmed cup.  At the group showerhead the te=
mperature is much higher.  I measured that too using imperfect methods.
I want to clarify the sour taste if I can.  It is not prickly or tacky, i=
t is the "off" taste like sour milk -- but again, without the tackiness or =
metallic perception you might get from sour milk.
Your other suggestions are good, I've brewed in an Aeropress everything I'v=
e put in the machine, and they all taste pretty good to great.  The blend=
s I've been using lately are Espresso Forte (Peet's) and Toscano (CCC).
My grinder is a used Mazzer Mini, and I've been told that worn burrs can ca=
use a sour taste, and to install new burrs.  I'm doing that next, we'll s=
ee if that has an effect.
Regarding cleaning: is minute rice more effective than manual cleaning?  =
I've been using a toothbrush & vacuum cleaner to get gunk off there.  I'm=
 sure there are oils left after my cleaning though.  I don't taste bitter=
 or rancid in my AP brews...
I should've decalcified & cleaned out the New Baby more throughly (I only t=
ook off the showerhead), but the Classic is brand new.
It seems like you covered all the bases.  There's channelling, which is s=
upposed to be another possible cause of underextraction.  At this point I=
 believe I'm preparing the puck fairly well.  We'll see what the new burr=
s do.
-Mike
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7) From: Bryan, Compass Coffee
To be honest, if you have light crema and the shots are going from dark to =
blonde nearly instantaneously, I don't think you have a machine problem, it=
 sounds to me like you have a beans problem.  How old are they?  Both t=
oo fresh and too stale will do the things you've described.  How are you =
storing them?
What's your dose weight vs your yield weight and how long is it taking to g=
et there?
Before you go off tearing apart all of your equipment and replacing half of=
 it let's get a little more info.
-bry
 From: denis bordeleau 
To: "A list to discuss home coffee roasting. There are rules for this list,=
 available athttp://www.sweetmarias.com/maillistinfo.html" =
Sent: Wednesday, June 6, 2012 1:51 PM
Subject: [Homeroast] Re :  Sour espresso taste
 =
Hi Mike,      Thanks for the come back.  We all appreciate. =
   The test with the AeroPress might be  unconclusive at 50% becaus=
e of the paper filter that retains the coffee oily elements. Also, try =
a manual or other grinder if you have one. Put Instant Minute Rice in the M=
azzer Mini with the old burrs inside  and try again an alternate brewing =
method without paper filter.  Unscrew the brewgroup filter and gasket of =
both the Baby and Classic Gaggia and compare them. May be "Brand New" meant=
 an open box or a demo.  Use citric acid and vinegar at that moment.  C=
heck the brew group filter holes and clean with the small provided needle t=
ool if necessary.  Be sure you use the double cup Portafilter size and =
that this filter is not clogged due to your  too fine grindings and too h=
eavy Weiss technic tampering in the past that caused channelling and it=
 will confirm that your problems and effort to resolve them are not fixin=
g the original
problems but only the symptoms that are now showing.  We don't all die =
because we are born; that's probably due to something in between or vice-ve=
rsa.  Keep on and you will enjoy the cup you deserve.      De=
nis 
De : Mike Wilkens 
À : homeroast =
Envoyé le : mardi 5 juin 2012 15h19
Objet : Re: [Homeroast] Sour espresso taste
  =
Hi Denis, those are all great suggestions.  Regarding temperature, I thin=
k 168*F coffee temperature measured in the cup is good or even on the high =
side.  This is measured after the water has gone through the coffee, and =
through the air, and into the warmed cup.  At the group showerhead the te=
mperature is much higher.  I measured that too using imperfect methods.
I want to clarify the sour taste if I can.  It is not prickly or tacky, i=
t is the "off" taste like sour milk -- but again, without the tackiness or =
metallic perception you might get from sour milk.
Your other suggestions are good, I've brewed in an Aeropress everything I'v=
e put in the machine, and they all taste pretty good to great.  The blend=
s I've been using lately are Espresso Forte (Peet's) and Toscano (CCC).
My grinder is a used Mazzer Mini, and I've been told that worn burrs can ca=
use a sour taste, and to install new burrs.  I'm doing that next, we'll s=
ee if that has an effect.
Regarding cleaning: is minute rice more effective than manual cleaning?  =
I've been using a toothbrush & vacuum cleaner to get gunk off there.  I'm=
 sure there are oils left after my cleaning though.  I don't taste bitter=
 or rancid in my AP brews...
I should've decalcified & cleaned out the New Baby more throughly (I only t=
ook off the showerhead), but the Classic is brand new.
It seems like you covered all the bases.  There's channelling, which is s=
upposed to be another possible cause of underextraction.  At this point I=
 believe I'm preparing the puck fairly well.  We'll see what the new burr=
s do.
-Mike
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8) From: Andrew Fresh
On Fri, Jun 01, 2012 at 11:36:55PM -0700, Mike Wilkens wrote:
<Snip>
How long does it take to get ~2oz into the cup?  If it is way less than
30 seconds then that would point to channeling or too coarse a grind.
What is your tamping procedure? Does your tamp fit your PF well and how
much pressure are you using for tamping?
l8rZ,
-- 
andrew -http://afresh1.comThe 3 great virtues of a programmer: Laziness, Impatience, and Hubris.
                      --Larry Wall
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9) From: Michael Mccandless
Just went through something similar - but the flow was slow.
Adjusting the grind changed the shot time, but deviated quite a ways from
the norm.
The fix was a disassembly - descaling.
The test that told the story was the empty portafilter test.
Lots of differing numbers floating around out there:
*35-55 ml of water in 6 seconds.    *
*450 to 500 ml/minute *
*90/120 ml (3-4 fl oz) per 10 seconds*
*Try it - should give an idea if you're in the ballpark or need descaling.*
*
*
*Mike Mc*
On Sat, Jun 9, 2012 at 9:27 PM, Andrew Fresh  wrote:
<Snip>
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10) From: Mike Wilkens
Thanks all for the feedback on the espresso taste!  I believe I'm now able to better control temperature on the Gaggia Classic.  My problem may be partly a thermostat that opens a little too quickly (making water a little too cold), but also I was following advice to draw water just before making a shot (to turn the heater on), and that was cooling down the brew water by 13*F.  Plus it cooled the group down by 10*F.  Flushing water seems like a counter-productive procedure on this machine.
As a result of controlling brew temperature, shots no longer taste intensely sour (sour cream sour), but instead taste sharp, metallic, maybe salty.  Not burnt.  Crema color is no longer yellowish tan, but instead medium brown or even reddish brown, which looks normal to me.  Crema amount is pretty small (maybe 10-25%), and flow is thin.
The taste I described may be normal too, or temperature may still be a little low.  I have to use the steam switch to get the unit up to temperature consistently.
I've been grinding finer aiming for about 2 oz in 28 s, although my best tasting coffees have been lungos.  (Probably not a good sign!)  I use 14 g or 15 g doses (+- 1 g).
In general grinding finer lowers the flow, plus, for espresso brewing, it changes the distribution of sour, sweet, and bitter that you get during extraction.  The sour part, the initial part, is shortened.
One thing I tried is continuously tasting the flow as it came out.  It tastes remarkably different at different times.
Andrew: you mentioned the water debit test: I get 100 ml of water in 10 seconds.
-Mike
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11) From: Mike Wilkens
Thanks again to all who have made suggestions.  I can banish the sour taste (sour as in sour cream) by raising temperature.  I get almost no crema with my shots, and I'm told I should see 50% or more crema by volume once the pull is finished.  I tried fresh Brazil beans today, 2 days since roasted, and got almost zero crema.
John, I think you're right to bring up pressure.  I'm told low pressure can cause less crema, and I understand that lever machines, which use less pressure are known for giving smoother shots with less crema.  I spent a few hours experimenting with the OPV on the Gaggia, but no difference in taste or crema.  Yes, I've done many experiments with the styrofoam cup!  That's how I found out that pulling water was lowering the temperature significantly.  That said: for all I know it could be low pressure and not low temperature that was "causing" the sour taste.  There's more than one way to fix an issue, and espresso is sensitive to the combination of temperature and pressure.
Yesterday I decided to give up on espresso for now.  Even when I can salvage a shot as a cappuccino, it has an unpleasant metallic-chemical taste that actually makes me feel a little sick, and sticks around as an aftertaste.  The espresso, which is probably comparable to what you can get in most cafes, is really not enjoyable.  I'm sure something is still wrong, but at this point it looks like a PID is necessary for brew temperature, and a pressure gauge is next.  It seems like there's always another problem, another variable, another piece of equipment to buy with espresso.
I brewed the Brazil in the Aeropress, and it has a surprisingly good taste, delightful and different.  I can get good coffee out of the espresso machine, but at its best it is a murky, muddy simulacrum of what I get in the Aeropress.
-Mike
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12) From: denis bordeleau
Hello Mike.     You are still looking for a good espresso shot but =
without success.  This is normal.     You enjoy the taste of two =
days since roasted single origin Brazil beans made from an Aeropress.   W=
hat is the torrefaction degree?  I told you about the fact that a paper=
 filter can keep the oil from the cup and some coffee drinkers like it that=
 way.   I made a research on Google by typing:  -aeropress paper filt=
ers- and got on the Aerobie Aeropress (tm) FAQ site and the metallic taste =
was the first subject. You should try a french press or any non espresso no=
n paper filter method to be sure that you can enjoy a coffee with the oily =
elements still in.    About the crema, since we are most of us homero=
asters, we are also home blenders and I found it difficult myself to get ni=
ce crema with a single origin materia.  Most of the time we have to roast=
 the beans we put in our espresso blends one by one to be sure that each of=
 it will get
 the best of itself and we may add some robusta, plus other secret tricks..=
.        It is very hard to resolve the equation of a good co=
ffee without  unvoluntarily adding another variable.    At least, y=
ou should have another taster to be sure you are not the only one to have t=
his metallic taste like we see in some common  curable medical conditions=
 .      So, find another guinea pig besides your own gustatory re=
ceptors.  Check a brew without paper filter.    Keep it simple and =
you'll have good stew without the PID.         Denis
 =
 De : Mike Wilkens 
À : homeroast =
Envoyé le : vendredi 15 juin 2012 14h47
Objet : Re: [Homeroast] Sour espresso taste
  =
Thanks again to all who have made suggestions.  I can banish the sour tas=
te (sour as in sour cream) by raising temperature.  I get almost no crema=
 with my shots, and I'm told I should see 50% or more crema by volume once =
the pull is finished.  I tried fresh Brazil beans today, 2 days since roa=
sted, and got almost zero crema.
John, I think you're right to bring up pressure.  I'm told low pressure c=
an cause less crema, and I understand that lever machines, which use less p=
ressure are known for giving smoother shots with less crema.  I spent a f=
ew hours experimenting with the OPV on the Gaggia, but no difference in tas=
te or crema.  Yes, I've done many experiments with the styrofoam cup!  =
That's how I found out that pulling water was lowering the temperature sign=
ificantly.  That said: for all I know it could be low pressure and not lo=
w temperature that was "causing" the sour taste.  There's more than one w=
ay to fix an issue, and espresso is sensitive to the combination of tempera=
ture and pressure.
Yesterday I decided to give up on espresso for now.  Even when I can salv=
age a shot as a cappuccino, it has an unpleasant metallic-chemical taste th=
at actually makes me feel a little sick, and sticks around as an aftertaste=
.  The espresso, which is probably comparable to what you can get in most=
 cafes, is really not enjoyable.  I'm sure something is still wrong, but =
at this point it looks like a PID is necessary for brew temperature, and a =
pressure gauge is next.  It seems like there's always another problem, an=
other variable, another piece of equipment to buy with espresso.
I brewed the Brazil in the Aeropress, and it has a surprisingly good taste,=
 delightful and different.  I can get good coffee out of the espresso mac=
hine, but at its best it is a murky, muddy simulacrum of what I get in the =
Aeropress.
-Mike
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13) From: Bryan, Compass Coffee
Your equipment is clean right?  If you have spouts on your portafilter ma=
ke sure that you are cleaning them after each session.  Scrub the screen =
with a Purocaff soaked towel after each session as well.  Contrary to a l=
ot of talk out there, pulling just one shot and the letting a hot machine c=
ool off is more than enough coffee oil to turn a machine's screen rancid.
Clean up your portafilter really well if you haven't and then give it anoth=
er go.  Also, what grinder did you say you were using?  If you did tell=
 us, it was long ago enough that I've forgotten.
I'd stop basing your shot's success on the crema.  Crema doesn't mean a d=
amn thing.  Close your eyes from the time you turn on your pump until you=
 drink your shot.  What does 50% crema taste like?  75%?  100%?  If=
 anything, crema is the most unappealing flavor component of the shot.
Push for a 16g dose, 28 seconds to a 28g yield (around 1.5 ounces).  Stir=
 in the crema, let the shot sit for 3 minutes and then tip it back and eval=
uate the flavor.  Try this with that Brazil once it has hit day 7 and I b=
et you will have a much different opinion of your espresso shots.
Regarding the comment about 30g being a spot on shot for a 14g dose... it w=
ould help to look at Counter Culture's suggested parameters before correcti=
ng me.  They recommend an 18.5g dose yielding 1.5-1.75 ounces (or about 2=
7-28g yield).  Considering he's dosing 14-15g he should be aiming for abo=
ut 1-1.25 ounces per Counter Culture's recommended parameters.  Ristretto=
 is not at all an "advanced" method of producing espresso.  Quite the con=
trary.  Ristretto is much easier to coax sweet, predictable flavors from =
than a normale.  The longer you let a shot run out the more variables you=
r are letting enter the equation.  This is why pretty much all ristretto =
shots taste the same: sweet chocolate leading to a slightly salty caramel f=
lavor with a tart cherry finish, wrapped up in a syrupy mouthfeel.  Sound=
 familiar?  It's because this is how nearly every ristretto-uber ristrett=
o shot on the planet is going to taste.  It has more to do with the % of
 solubles in the finished cup than a simple Yield/Dose=Brew ratio equatio=
n.  You can't evaluate based on these parameters because as your dose inc=
reases your coffee bed depth increases as well, changing the ratio of surfa=
ce area to bed depth.  This is why a shot on a 53mm machine will taste di=
fferent than a shot with the exact same parameters on a 58mm machine.
-bry
 From: denis bordeleau 
To: "A list to discuss home coffee roasting. There are rules for this list,=
 available athttp://www.sweetmarias.com/maillistinfo.html" =
Sent: Monday, June 18, 2012 12:11 PM
Subject: [Homeroast] Re :  Sour espresso taste
 =
Hello Mike.     You are still looking for a good espresso shot but =
without success.  This is normal.     You enjoy the taste of two =
days since roasted single origin Brazil beans made from an Aeropress.   W=
hat is the torrefaction degree?  I told you about the fact that a paper=
 filter can keep the oil from the cup and some coffee drinkers like it that=
 way.   I made a research on Google by typing:  -aeropress paper filt=
ers- and got on the Aerobie Aeropress (tm) FAQ site and the metallic taste =
was the first subject. You should try a french press or any non espresso no=
n paper filter method to be sure that you can enjoy a coffee with the oily =
elements still in.    About the crema, since we are most of us homero=
asters, we are also home blenders and I found it difficult myself to get ni=
ce crema with a single origin materia.  Most of the time we have to roast=
 the beans we put in our espresso blends one by one to be sure that each of=
 it will get
the best of itself and we may add some robusta, plus other secret tricks...=
        It is very hard to resolve the equation of a good cof=
fee without  unvoluntarily adding another variable.    At least, yo=
u should have another taster to be sure you are not the only one to have th=
is metallic taste like we see in some common  curable medical conditions=
 .      So, find another guinea pig besides your own gustatory re=
ceptors.  Check a brew without paper filter.    Keep it simple and =
you'll have good stew without the PID.         Denis
De : Mike Wilkens 
À : homeroast =
Envoyé le : vendredi 15 juin 2012 14h47
Objet : Re: [Homeroast] Sour espresso taste
  =
Thanks again to all who have made suggestions.  I can banish the sour tas=
te (sour as in sour cream) by raising temperature.  I get almost no crema=
 with my shots, and I'm told I should see 50% or more crema by volume once =
the pull is finished.  I tried fresh Brazil beans today, 2 days since roa=
sted, and got almost zero crema.
John, I think you're right to bring up pressure.  I'm told low pressure c=
an cause less crema, and I understand that lever machines, which use less p=
ressure are known for giving smoother shots with less crema.  I spent a f=
ew hours experimenting with the OPV on the Gaggia, but no difference in tas=
te or crema.  Yes, I've done many experiments with the styrofoam cup!  =
That's how I found out that pulling water was lowering the temperature sign=
ificantly.  That said: for all I know it could be low pressure and not lo=
w temperature that was "causing" the sour taste.  There's more than one w=
ay to fix an issue, and espresso is sensitive to the combination of tempera=
ture and pressure.
Yesterday I decided to give up on espresso for now.  Even when I can salv=
age a shot as a cappuccino, it has an unpleasant metallic-chemical taste th=
at actually makes me feel a little sick, and sticks around as an aftertaste=
.  The espresso, which is probably comparable to what you can get in most=
 cafes, is really not enjoyable.  I'm sure something is still wrong, but =
at this point it looks like a PID is necessary for brew temperature, and a =
pressure gauge is next.  It seems like there's always another problem, an=
other variable, another piece of equipment to buy with espresso.
I brewed the Brazil in the Aeropress, and it has a surprisingly good taste,=
 delightful and different.  I can get good coffee out of the espresso mac=
hine, but at its best it is a murky, muddy simulacrum of what I get in the =
Aeropress.
-Mike
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14) From: Jim Gundlach
On Jun 18, 2012, at 4:11 PM, Bryan, Compass Coffee wrote:
<Snip>
When I pulled my shot this morning it was topped with a good half inch  
of crema.  But while I was grinding the coffee for that shot the knob  
fell off my forty-three pound grinder and in the time it took me to  
get the knob back on and turn it off it ground enough for a second  
shot.  Well I am getting low on greens, I will order tomorrow, so I  
decided to go ahead and use the extra ground coffee for my afternoon  
shot.  Low and behold:  No crema.  Doesn't taste as good either.   
Anyway a imputed  correlation based on an N of two, which should not  
be calculated because N is less than three, a loss of crema predicts a  
loss of flavor.
pecan jim
A retired professor who taught statistics to math hating students for  
over thirty years.
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15) From: Bryan, Compass Coffee
So you're telling me that a shot that you ground hours before you brewed it=
 tasted flat and lifeless?!  Miraculous!
What I was getting at with that comment (as was rather obvious) was that ba=
sing a shot on whether it has 10% crema or 25% crema or 100% crema, dark ye=
llow or light brown, dark flecking or tiger striping, is completely useless=
 because there aren't any absolutes.  If I have a shot with dark crema, r=
eddish hue and great flecking and then I pour it from one vessel to another=
 it's going to become much lighter, with no flecking at all.  Does it tas=
te worse?  Nope, just looks different.
Relatively fresh dry processed coffee will always give you more crema than =
relatively fresh wet processed coffee.  Does that mean that dry process w=
ill always taste better than wet processed?  Obviously not.
The point of the email was to not focus on what the crema is doing, but ins=
tead to focus on things that are ACTUALLY absolutes: weights and time.
Can crema be a visual aid to whether your parameters were in check?  Sure=
.  Should you judge a shot based on how much crema it has or what color t=
he crema is without tasting it?  Nope.
-bry
 From: Jim Gundlach 
To: "A list to discuss home coffee roasting. There are rules for this list,=
 available athttp://www.sweetmarias.com/maillistinfo.html" =
Sent: Tuesday, June 19, 2012 2:05 PM
Subject: Re: [Homeroast] Re :  Sour espresso taste
 =
On Jun 18, 2012, at 4:11 PM, Bryan, Compass Coffee wrote:
<Snip>
 damn thing.
When I pulled my shot this morning it was topped with a good half inch of c=
rema.  But while I was grinding the coffee for that shot the knob fell of=
f my forty-three pound grinder and in the time it took me to get the knob b=
ack on and turn it off it ground enough for a second shot.  Well I am get=
ting low on greens, I will order tomorrow, so I decided to go ahead and use=
 the extra ground coffee for my afternoon shot.  Low and behold:  No cr=
ema.  Doesn't taste as good either.  Anyway a imputed  correlation ba=
sed on an N of two, which should not be calculated because N is less than t=
hree, a loss of crema predicts a loss of flavor.
pecan jim
A retired professor who taught statistics to math hating students for over =
thirty years.
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16) From: Martin Maney
On Tue, Jun 19, 2012 at 04:05:49PM -0500, Jim Gundlach wrote:
<Snip>
Of course, grounds that have sat for how many hours are far more likely
the cause of both of the changes you observed, eh?
-- 
I must say I find television very educational.
The minute somebody turns it on,
I go to the library and read a good book. -- Groucho Marx
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17) From: Jim Gundlach
On Jun 19, 2012, at 5:22 PM, Bryan, Compass Coffee wrote:
<Snip>
This is well said.  Sometimes very little crema is offered by a very  
good shot.  But, I really doubt that any espresso system that never  
produces crema when given a variety of good freshly roasted beans that  
are ground and tamped so they take about  thirty seconds to draw a  
shot is worth buying or keeping.
   pecan jim
    I might also add that since my brain infection I am not very good  
at writing or saying what I intend to.  My wife thinks that when I  
asked to bring my chain saw with me when I went to the hospital I was  
misnaming my laptop computer.  I am no longer that far off but I still  
do have a great deal of difficulty writing in such a way that I get my  
thoughts across.
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18) From: Michael
So really you're just like the rest of us folks of a certain age, though you may have a better excuse for it than we do.
On Jun 21, 2012, at 11:55 AM, Jim Gundlach wrote:
<Snip>
michaelb
espressoperson
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19) From: Sandy Andina
I know plenty of hospitals that'd be improved by a chain saw.  But the one I'm entering tomorrow has several of its own. (Getting a knee replacement). Fortunately, it also has a decent e-bar (non-Starbucks) in the lobby and "concierges" to deliver me my caffeine delivery device of choice.  (In the recovery room, it'll be mainlining. No, really--they can do that, straight into the I.V.).  
On Jun 21, 2012, at 10:55 AM, Jim Gundlach wrote:
<Snip>
Peace & Song, 
Sandy Andina
www.sandyandina.com
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