HomeRoast Digest


Topic: The 28 second shot? (18 msgs / 526 lines)
1) From: TodA@alltel.net
I'm playing with my Krups Gusto, and have a question about TIME.  Here 
are my variables:  roast, grind, tamp (using a Thor tamper), time.  
Using filtered water, and 14 minute roasts on my modified FreshRoast, 
with about 12g-13g in the double filter.  I'm wondering, what is the 
longest time a shot can take, and not be over-extracted?  I've been 
adjusting the grind and the tamp, and can't seem to pull over 23 seconds 
without getting bitterness in the cup (after cleaning everything, to 
make sure residue isn't the problem).  In fact, closer to 20 seconds 
tastes better.
How do you get a 28 second shot, as I've heard.  Any Krups Gusto owners 
out there?  Should the grind be slightly finer, slightly coarser?  
Should I tamp slightly harder, slightly lighter?  Any suggestions?  Or 
shouldn't I even be worried about it?
- Tod, who manages to get loads of creama every time now

2) From: Angelo
Grind finer and/or tamp harder....
<Snip>

3) From: Edward Spiegel
At 12:16 PM -0400 7/23/04, TodA wrote:
<Snip>
A couple of suggestions:
For testing purposes, get one of those shot glasses from Starbuck's or Peet's that has one and two ounce markings on it. Pull a shot into one of these. Carefully watch the color of the stream of coffee. As soon as it start to change color to a light brown, stop the pull and note the volume in the shot glass and the time it took to pull.
Taste the shot. How does it taste?
Did the shot reach the two ounce mark before the color of the coffee stream changed color?
The color of the coffee stream is usually a reliable indicator of when the shot has been overextracted. It is IMHO the best indicator.
If you want great 25 second shots, you need to adjust the grind and quantity and tamp so that at 25 seconds the color has not gotten light. When the stream turns to a light color, the shot has bitter components in it.
For what it is worth, I have had 15 second shots that tasted great -- as long as I stopped before the stream changed.
I have noticed that a lot of people don't realize how little coffee 2 ounces are (a double shot is 2 to 2.25 ounces). Until we got a shot glass to calibrate ourselves, my wife and I were tending to pull shots quite a bit larger than we should have.
With every roast that I perform (or purchase), I find that I have to pull a few shots to find the right grind/tamp/grounds level in the portafilter to pull a great shot.
Here is what I do:
I consider grind 3 on my Gaggia MDF to be my baseline setting. I grind the coffee and put the appropriate amount in the portafilter and temp  moderately. About 1/2 the time, I get the shot that I want. If I don't get the shot I want, I do something like this:
If the initial shot extracted a LITTLE bit too fast (lets say 15 seconds), I put a little bit (not much) more coffee in the portafilter and tamp harder and try again.
If the initial shot was way too fast (lets say 10 seconds), I grind finer and tamp with the same force as the first shot. If this shot is too fast, I try with the same grind and tamp harder.
If the initial shot was too slow (rarely happens at my 'baseline' grind of 3), I try the next shot with the same grind and a tamp lightly (just enough to level and smooth the ground coffee).
I also generally find that as the week progresses that I have to tamp a little more firmly.
I hope this helps,
Edward

4) From: Chris Tacy
(note: everything below is based on commercial equipment - because i don't
know anything about home equipment)
general rule of thumb is to eliminate all variables except grind.
in other words, make all other variables as consistent as is possible and
only adjust the grind.
the currently accepted values for the other variables (according to the
majority, though there are dissenters) are:
  dosage - enough to fill the basket, when tamped, to 3mm below the
dispersion screen. in other words, dose by volume rather than by weight.
  tamp - 30lbs of pressure (traditional methodology is light tamp with
twist, light tap, tamp with 30lbs, light polish).
  shot volume - between 2.5 and 3 ounces for a lungo double and around 1.5
ounces for a ristretto double.
  brew temp - depending upon the espresso beans (blend and roast) between
190F and 205F at sea level (most "high end" espressos seem to do well
between 200F and 203.5F).
  brew pressure - between 8.2BAR and 9BAR
  extraction time - between 25 and 30 seconds
as for culprits for your problem... i would look at the brew temp of the
machine (anything over 205F tends to result in bitter and/or burnt
flavours), your beans (are they very dark roast), your brew pressure
(pressure that is too low can result in extraction of "off" and sour and/or
bitter flavours) and your distribution and tamp (uneven distribution and/or
too light a tamp will result in uneven extraction - where some coffee is
overextracted and some under resulting in espresso that is both bitter and
sour).
focus on the variables that need to be as close to constant as possible. get
then dialed in, and then tune by adjusting the grind. will work wonders for
you!
good luck.
-c

5) From: R.N.Kyle
When I used a Gusto I found that the 49mm filter basket would not handle
anymore then 14 grs of coffee. The pull for a really good sweet shot was 17
sec to 20 sec.
RK

6) From: Allen Marsalis
At 10:03 AM 7/23/2004 -0700, Edward Spiegel wrote:
 >
 >I also generally find that as the week progresses that I have to tamp a
 >little more firmly.
 >
I notice this as well.  And in some cases, I must grind progressively
finer each day as the batch rests.  An extreme example was when I left
for vacation. I left with the grinder dialed in perfectly.  I roasted
while on vacation but returned home empty handed.  Even though my old
beans left in the hopper were a week old, I wanted some coffee and
I thought I would give it a try.  The resulting shots were very fast/thin,
around 10-15 seconds.  I had to move around 2 notches on the Mazzer to
get a 25 second shot from the same beans.  I was mystified and guessed
that beans get a little harder each day that they rest while they
gas off or loose moisture or something like that.
Allen
am

7) From: Chris Tacy
for what it's worth, a skilled professional barista will adjust the grind
between 20 and 50 times per shift on average.
grind is never constant. it's the one variable you tune your shots with.
-c

8) From: John Blumel
On Jul 23, 2004, at 7:20pm, Chris Tacy wrote:
<Snip>
I wonder if this isn't more of an issue in a commercial environment 
than in a home. Since shot frequency is much higher, there's a lot more 
steam flying around, and there are, it would seem, other factors that 
might make temperature and humidity levels much more variable, it may 
be necessary to change the grind much more frequently than in an air 
conditioned/heated home.
I also have noticed that I tend to keep adjusting the grind finer as a 
roast ages and loosening it for new beans. I rarely have to grind 
coarser for an aging roast, throughout the day or week.
John Blumel

9) From: Allen Marsalis
Thanks for the info Chris.  It seems very sensible to nail
down all of the variables except for one which is then controlled
for the desired result.
I learned this tuning carburetors.  It is best to adjust only
one parameter at a time and then test/measure the results.
If you change two things, all bets are off!  That pretty much
goes for anything with 2 or more inputs!
Allen
am
At 04:20 PM 7/23/2004 -0700, Chris Tacy wrote:
 >for what it's worth, a skilled professional barista will adjust the grind
 >between 20 and 50 times per shift on average.
 >grind is never constant. it's the one variable you tune your shots with.
 >
 >-c
 >
 >

10) From: Chris Tacy
it probably has more to do with the fact that you're pulling shots over
time, as temperature changes, humidity changes and barometric pressure
changes. and, of course, these changes are usually VERY minute in nature.
on the other hand, it demonstrates that the myth of a "correct setting" for
espresso grinders is just that - a myth.
-c

11) From: John Blumel
On Jul 23, 2004, at 8:03pm, Chris Tacy wrote:
<Snip>
Although the, "it probably has more to do with," seems to indicate that 
you are disagreeing with my conjecture, I'm not sure exactly what your 
saying here.
John Blumel

12) From: Chris Tacy
instead of pulling a couple shots in the morning, you're pulling shots
continuously throughout the day, as ambient temperature, humidity and
pressure changes.
-c

13) From: John Blumel
On Jul 23, 2004, at 8:53pm, Chris Tacy wrote:
<Snip>
I am pulling shots throughout the day, rather than just a couple once a 
day, but usually with at least an hour between shots. However, since my 
house is air conditioned (or heated in the winter), with the 
temperature and humidity remaining relatively constant over a period of 
hours and days, these factors don't seem to be having a significant 
effect on the need to change grind. Rather, the age of the roast seems 
to be the main factor. (Of course different roasts and beans can vary 
considerably but I'm focusing on minor adjustments required for a 
specific batch of coffee and not the sometimes major adjustments 
required for different beans and roast levels.) The required 
adjustments to keep shot times optimal seem to be mostly one way -- 
i.e., finer -- as the roast ages with only occasional instances when a 
coarser grind is required.
Since Allen had related a similar behavior and your reply seemed to 
imply that, in your experience in a commercial environment, frequent 
bidirectional adjustments were necessary, I was hypothesizing that a 
commercial environment might have more variable temperature and 
humidity -- because of the more frequent but also more variable use of 
the machines and more frequent use of steam wands -- and that that 
would explain your need to make more frequent adjustments both coarser 
and finer. Of course, you didn't actually say that you were adjusting 
both directions so I may have read that incorrectly into your reply. 
(I'm still not really sure whether you (Chris) are agreeing or 
disagreeing with this. Maybe I'm just a bit dense tonight.)
Of course, it's only a theory, but I've recently been wondering how 
much of the accepted wisdom on espresso applies completely to home 
'baristas' since so much of it ultimately comes from Schomer and others 
on the commercial side. Not that they are wrong, but it may be that one 
doesn't need to follow their techniques exactly.
For example, 30 lbs is frequently cited as the correct tamp pressure -- 
a number that seems to come from Schomer. But how did Schomer arrive at 
a 30 lb tamp as the 'correct' pressure? Did he do extensive tests with 
various tamps and grinds to finally arrive at this number? Or, did he 
determine that this was the optimal pressure for male and female 
baristas to consistently obtain? A higher pressure could be difficult 
for less muscular baristas to reach consistently over a working day and 
a lower tamp force might require more 'feel' to achieve consistently 
and thus be more variable from barista to barista. (Obviously, it's 
important that all the baristas at a shop use the same tamp pressure, 
otherwise they'll be constantly wasting shots as they adjust away from 
the optimal grinds of other baristas.)
Of course, there probably is at least some optimal range of optimal 
tamping force. Compensating for too coarse a grind with a really heavy 
tamp may have a limit beyond which it's impossible to get proper 
extraction. Likewise, there may be a limit to how fine a grind and 
light a tamp one can use and avoid inevitable over extraction. (I seem 
to recall this -- especially using a very fine grind with just a 
leveling tamp -- was a hot topic on alt.coffee a while back but I don't 
really follow that forum consistently so I don't know if it was ever 
resolved definitively.)
A similar question might be asked about optimal shot time. If I decide 
to adjust my tamp to a consistent 25 lbs and, necessarily, use a finer 
grind, does the optimal shot time change from say 25 to 20 seconds or 
is 25 some sort of magic number that the grind and tamp should always 
work out to?
Anyway, if you've read this far, you're probably wondering what my 
point is and, quite frankly, I almost forgot myself. Among other things 
related to his thread, I'm wondering whether it is necessarily the case 
that I will need to be adjusting my grind finer and coarser from shot 
to shot and am I just being lazy and ignoring the signs that it's off 
or is my home environment just different from a coffee shop and are a 
different set of expectations in order.
(Not that I expect anyone can definitively answer this for me but it 
would be interesting to know if others find that they typically need to 
adjust both fine and coarse with a single batch of coffee or if the 
adjustments, once an optimal shot is produced, tend to be in a single 
direction as the batch ages. And of course, it would be useful to know 
how much environmental variation seems to go along with these 
adjustments.)
Beyond that, I've recently been wondering whether the conditions for 
producing a good shot of espresso are really quite as rigid as they are 
often portrayed or whether there are actually quite a number of 
variations of conditions that will all result in a good shot. And, can 
changing one factor be compensated for by changing just one other 
factor or does changing one force changes in all the factors? Of 
course, being more of a theoretician than an experimentalist, I haven't 
yet done much more than wonder about these things.
John Blumel

14) From: Edward Spiegel
At 10:47 PM -0400 7/23/04, John Blumel wrote:
<Snip>
I can tell you for sure that the conditions are not that rigid for getting great shots BUT there are so many variables involved that I think (like almost all cooking with a lot of variables), it has proven practical to pass on a few 'rules' carved in stone -- because for most people negotiating the parameter space of all those variables proves to be their undoing.
From experience, I can say that it is possible to get a GREAT shot that pulls in fifteen seconds -- for instance -- that in a blind tasting holds up great against a canonically pulled 25 second shot. But, things would get way too complicated if everyone tried to pull shots by being sensitive to all of the parameters. And, of course, it is highly machine dependent. The 25 to 30 second godshot requires a machine calibrated (i.e. the pressure and temperature) like the professional machines.
In my opinion, the key is to focus on mastering the canonical method and then explore the parameter space to see if another combination of parameters yields equivalent results. On my machines (a Rancilio Betsy and Gaggia MDF grinder), there are times with certain coffees that a 15 to 20 second shot will be every bit as good as the 25 second shots -- but I have to be careful to make sure and cut the pull based on the color in those cases because they can roll along fast enough that you overextract.
I think a little flexibility is acquired with time and is required unless one measures the coffee precisely for every shot and has the machine re-calibrated every so often.
Anyway, that is my .02
--Edward

15) From: AlChemist John
One of the main things I recall from my intro days into espresso is that in 
general it is easier to achieve a good short fast  shot than a longer 
one.  I finally settled on 23 seconds as my "goal".
Sometime around 10:35 PM 7/23/2004, Edward Spiegel typed:
<Snip>
--
John Nanci 
AlChemist at large
Zen Roasting , Blending & Espresso pulling by Gestalthttp://www.dreamsandbones.net/blog/http://www.chocolatealchemy.com/

16) From: Chris Tacy
well stated!
-c

17) From: TodA@alltel.net
Wow, thanks everyone for their input, especially the "pro's" and the 
Krups owners (thx Ron for the confirmation that my little Krups may not 
allow me to do a "proper" 25-second shot).  I took alot of notes, and 
will be perfecting my technique.
Oh, I did notice that I get "color" longer with a finer grind, but it's 
still a little bitter past 20 seconds.  Might be water temp; I follow 
Ron's suggestion for running some water thru until the orange light 
comes on, then 10 seconds on the steam knob at lowest setting to adjust 
temp back up.  No readings to tell me where final temp ends up.  Was 
planning on a digital meter anyways.
Other than that, I'll just keep dialing in, and saving up for a better 
machine. :o)
- Tod

18) From: Edward Spiegel
At 1:05 PM -0400 7/24/04, TodA wrote:
<Snip>
Tod,
Have you measured the volume of your shots? Maybe you have got a full shot already. The taste may change a bit before the color changes. Some people like that hint of bitterness and others don't.
Maybe a 15 to 20 second shot will work best with your set-up. If so, don't sweat it. Don't be intimidated by the 25 second 'rule'. For some machines and some coffees a faster pull may be the right thing -- your tongue and nose will tell you. There was a great posting on coffeegeek.com by a guy that pointed out that a lot of the 'rules' that people bandy about are based on particular pro machines, and he pointed out that for every machine -- especially home machines -- you have to do a little adjusting of technnique and that your taste should guide you. If you know what a good shot tastes like, and you are getting it in less than 20 seconds, don't second guess yourself.
There is also a matter of taste. Sometimes I do a short shot because the flavor profile of a shorter shot is different even when you are all set up to do the 'canonical' shot. There are 200 some odd chemicals in coffee and each has different solubility characteristics and volatility. So, the flavor that constitutes the 'ideal' may not even in perfect circumstances be what someone's preference is. (Another reason to be guided by your own taste).
Anyway, that's my .02


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