So – how many coffees? In January I drank 126 cups, so on average a daily consumption of 4.¹

Below is a quick breakdown of my consumption, as well as an explanation of what was logged, and what wasn’t.

What counts as a cup?  With brewed coffee this is usually a 6-8oz cup.  With cappuccinos they were usually single shot, 5oz drinks.  Flat whites² were double shots.

I didn’t log any coffee I drank as part of a training or when tasting to dial in a grind setting.  I didn’t include coffees I cupped, or brewed little tasters off rather than drank a cup of.  These were coffees I drank all of because I wanted coffee.

Daily consumption:

You can sort of see the dip at weekends here, though Sundays can often turn into very caffeinated days as I live so close to so much good coffee!  The 27th was the record day with 8 cups.

Let’s break down the total consumption into individual drinks.  I probably should have logged any brewed coffee as just “brewed” rather than the farm, but for various reasons I didn’t.  All espressos, regardless of blend, are logged as a group.

So – I drank a lot of espresso.  In fact, despite how much I moan about it, 51.6% of the coffees I drink are espresso.  Which seems quite high, but probably not unusual in the coffee community.

I’m actually a little disappointed in myself that brewed coffee only made up about 22% of my coffee consumption.

Here are a quick breakdown of my espresso based drinks and brewed coffees:

I hope I can keep tracking it for the rest of the year – though it is easy to forget.  Thankfully it is easy to post to daytum from my phone, or via twitter as well as through the web interface.  I am recording enough data so I can then break down my consumption into different countries throughout the year and other stuff, which might be interesting.

I guess this probably seems quite low – as daily consumption goes – but I found it interesting nonetheless!  If anyone has any questions then do let me know!

1. Well, 4.06 on average, but 4 is neater I suppose!
2. sick as those of us in the UK may be of them

At the London Gastronomy Seminars I was given a Mypressi Twist to play with by the UK distributor.  I had been toying with buying one having seen the hype online, so this was a rather pleasant surprise.

I didn’t really get a chance to play with it til yesterday afternoon.  I’ve played with it some more today and this is just a quick summary of my thoughts and what I think is particularly interesting about it.

First off – it makes pretty good espresso.  I know I am hardly the first person to make this observation, but I think everyone who tries it is pleasantly surprised.  I think with a few adjustments to technique then you can get something better than any espresso machine in its price bracket, or up to two or three times its price.  If you like milk drinks though – then this may not appeal to you.

I pulled a couple of shots yesterday, and for shot number three my curiousity kicked in.  What I think is most exciting about this is its potential for experimenting with extraction.  We can only really (safely) use water in an espresso machine.  My first thought was to reach for some whisky.  I probably should have heated it up first, as it was not delicious cold – though the shot did still look pretty good.  I then attempted a little macchiato using milk to brew the coffee.¹.  In hindsight I should probably have used skimmed milk, as the full fat seemed to clog the extraction and the result was (simply put) not good.  But there was potential!

This makes me quite excited about its possible use in barista competitions.  In the past it has been completely illegal to put anything other than coffee in the portafilter (for good reason!) but this would let you infuse anything you like.  You’ll still need to pull and use 4 shots from the competition espresso machine but the applications within signature drinks are almost endless.

You could brew espresso starting with brewed coffee.  You could use espresso and push it through something else to extract flavour into it.  In fact, I am going to pause writing this post and check how many shots you can get in the water section of the twist…..

*time passes*

OK – so 4 shots of espresso fit pretty nicely into the top chamber.  And the espresso seems to pull in a fairly normal (if slightly slow way).  This is a double espresso, brewed using 4 espressos:

The taste?  Not so great, not as bad as I was expecting, but not so great.  The texture was unbelievable.  The point is that this is exciting!  I should add that points for creativity in competitions don’t come from using clever things, or having a wild idea – they come from using clever things, or wild ideas to create something tasty.  There are no points for novelty.

The more I think about it, the more possibilities there seem – non-coffee applications too.  Cocktail people would surely have a million more ideas than me.  I still wonder though – what about pushing vodka through a basket of lemon and lime zest?  What if you use CO2 instead of N20? What if? What if? What if?

I’ve gotten off topic! Back to using it to brew coffee:

I have what not many other people have – a 53mm Scace, back from my days at La Spaziale.  The Mypressi uses a 53mm basket.  It didn’t take a giant leap of thought to dig out my device and start testing the brew temperature.  I’d seen quite a lot of speculation online about it, and I can only post my limited experiments and findings.  Here is a short video:

Preheating the water chamber is incredibly important.  You could tell this was later on in my experiments from the starting temp of the scace probe, which may have influenced readings somewhat.  Without preheating the temp was hovering around 80C.  I am sure I could have heated the top chamber more and squeezed into the 90s.  Nonetheless I think it is a pretty respectable brew temperature.  I’d love to hear how people are getting max temp out of theirs.

I was also a little surprised that the dose and grind I had set on my Synesso seemed to work well.  Out of curiousity I pulled a double on each simultaneously – same dose, same grind setting, same brew time.  Here is the video, data on the shots afterwards:

Synesso shot:  18.5g coffee, 33.4g brew liquid.  Extraction percentage 18.6%

Mypressi shot: 18.5g coffee, 42g brew liquid.  Extraction percentage 18.9%

This is a single experiment, so it would be foolish to take too much from it.  One could speculate that with the temperature issues the Mypressi will struggle to extract coffee as quickly as a hotter profile on a machine.  The fact that it took almost 25% more liquid to get the extraction percentage to match (in the same time frame – with very different pressure profiles I might wager, sadly I only have a 53mm Scace 1.0 – not 2.0) would suggest that if you like shorter shots you may be better off dropping your dose and going finer, and if you want a heavier dose you may need to push a little more water through.

So far I’ve only spent a couple of days with it – but overall I’m quite impressed and looking forward to playing with it some more.  I’ll take more more readings with the ExtractMojo, see if the above experiment was repeatable.  Would love to hear people’s thoughts, suggestions and ideas!

1. Tim Styles should trademark the term MilkPressi Twist

Is it me or is everyone else a little surprised at the lack of discussion of pressure profiling?

Most of the interesting discussion, if not just about all of it, has been over at home barista where various people are building pressure profiling units for their one group machines.  Still much of that discussion remains more about how to build it, than about desirable profiles.

Pressure profiling is undoubtedly going to become more readily available.  Though the capacities of the Slayer, the Strada and Cimbali’s new machine are all different, they are all chasing the ability to manipulate pump pressure to improve espresso.  A lot of this desire comes from the profile of espresso produced by lever machines, which have a very different pressure profile compared to a pump driven machine.

Perhaps I shouldn’t be surprised, given my own experiences with pressure profiling.  I was asked, a little while back, about why I hadn’t posted anything about it and I thought I would take this opportunity to explain:

John Ermacoff very kindly leant me a pressure profiler that he had built for a while.  I am not going to go into exactly how it worked, but we hooked it up to one of the groups in my 2 group Synesso.  This meant that I could only use one group at a time because then I had a Cyncra, not a Hydra, so the changes in pressure would influence both groups if they were open.

The machine allowed for almost any profile, and included a manual and automatic mode.  I played with the manual mode for a while, but prefered the automatic mode because it was repeatable and allowed me to make specific adjustments.

The entire time I used it I felt lost.  Juggling dose, grind size, flow rate, volume of espresso and time is enough.  Suddenly introducing pressure variations meant that it was a lot harder to isolate the problem.  If the shot was underextracted then keeping the profile but changing one variable often resulted in chasing my own tale and very quickly burning out my palate.

Changing the pressure even slightly undoubtedly changed the cup.  The impact was always obvious, but rarely did I ever feel as if I had genuinely improved the cup.  By giving me so much control I ended up lost in a sea of variables from which I never really found my way out.

I confess that I didn’t approach this as clinically as I should have.  I didn’t record enough data and often ended up defaulting back to a very simple profile – which seems to be quite a popular one online:

• - A relatively lower pressure preinfusion period, lasting long enough to soak the cake (5-8s depending on dose).
• - A smooth, relatively quick rise to 9 bars over 2-3s.
• - A period of 9 bars lasting 7-10s
• - A declining pressure in the remaining section, from 9 bars down to 8 or perhaps lower.

This is by no means what I would claim to be the perfect profile.  It is one, however, that I could rationalise in my head.  The period of preinfusion at the start would increase the likelihood of an even extraction.  The period of declining pressure in the final third meant that we were extracting the nearly-spent coffee less aggressively, yet still adding volume to the shot – aiding balance, and reducing negative flavours.  Of course you could easily tear this theory to pieces – I just couldn’t find a better way to explain it.¹

One thing that surprised me was how a lever machine acts, as I had initially thought this profile would be quite close to it.  I was quite wrong – though my experiences comes from the use of a Victoria Arduino Adonis and a Scace 2.

In terms of pressure the lever allowed line pressure through when pulled down, as the machine has a heat exchanger for brew water.  Upon releasing the lever the pressure shot up to around 12 bars before almost immediately starting to drop down towards 0 in a fairly linear fashion.  I only found this out after I had returned the profiler, and I wish I could have tried it on the Synesso.  That way I could have dose two identical baskets had a better idea of the influence of temperature on our love affair with lever espresso.  The Scace 2 showed that initially the brew water was very stable – in the first 12-15 second after pulling the lever the temperature barely moved – maybe 0.2/0.3°C.  Then the water gradually began to decrease in temperature, losing 4 or 5°C by the end of the shot.  This makes sense.  When the lever is pulled water fills the chamber above the coffee.  Only once it starts to pass through the coffee, and lose thermal mass, dose it really start to cool off.²

This profile is a very long way away from what most pressure profiling machines out there are doing – or at least what people have said they are doing.  Then again, as I said at the start, I can’t find many people talking much about it.  I guess I had hoped to see more on places like coffeed, coffeegeek, twitter or on various blogs.  Personally I’d be as interested in finding out what isn’t working for people, as much as what is.  When I asked the Cimbali engineer which profiles he liked best, he was a little evasive – in fact very few people are willing to really get behind any one profile.  I know these may change coffee to coffee, but with enough data out there I hope we’ll eventually be able to make a pretty good educated guess, the way we can with things like temperature and dose, based on the density of a particular coffee/blend.

I do have great hopes for pressure profiling, but at the same time realistic ones.  I don’t expect pressure profiling to discover sweetness, or flavours that have previously remained undiscovered in coffees.  I hope they can improve the clarity and presentation of them and help reduce detracting tastes and flavours.  It won’t make average greens taste great, or bad roasts acceptable.

Right now it seems that engineering is, for once, way ahead of the barista.  The pressure profiling machines coming can do almost anything we want – we just need to work out what that is…

I will close this post by saying thank you again to John Ermacoff – I learned a great deal through his incredibly generosity, and can’t wait to see what he comes up with next.

1. If anyone has any info on the effect of pressure at that stage in the shot – on caffeine extraction, oil emulsion etc etc then I would love to see it!
2. Again, correct me if I am wrong here

Back in 2006 I published a recommended reading list. Since that time my collection of books has (worryingly) increased so I thought I should probably update it. I could easily write a list of coffee books that one should avoid (having learned the hard way) but I suspect that would get me into rather a lot of trouble, so I shall leave that for now. I’ve broken it down into two parts and then down into sections, and have indicated which are nice to have, and which I would consider are essential on that subject.

I will try and keep this one updated – if you think I’ve missed something obvious then let me know.  I haven’t recommended books I don’t own, so this means some books may be missing that you would expect to see here.

This is quite a large post so if you want to skip down just click on the relevant section:

Part 1:

Espresso Preparation
Coffee History
Coffee Science
Coffee Origins

Part 2:

Coffee Growing
Coffee Roasting
Coffee Equipment
Hard to find/Rare Books

Espresso Preparaion

The Professional Barista’s Handbook – Scott Rao [Essential]

It often feels like no one is writing books on coffee any more, but this was a breath of fresh air. Detailed information on technique and theory, some new ideas well presented and written with an open mind.

Espresso Coffee: Professional Techniques – David Schomer [Essential]

I don’t think I know many coffee professionals who haven’t read this book. Whether you agree with some of his ideas, or his strict opinions on espresso preparation, you have to acknowledge the influence of both Schomer and his book. I read it twice through in one sitting when it first arrived, and it felt good to finally have a book that went some way to quenching my thirst for knowledge.

Technique may have moved on, but I think this will be a good and useful read for many more years.

Espresso Italiano Speciailist – Luigi Odello [Nice to have]

We often, as an industry, romanticise Italian Espresso while trying to do something totally different with our espresso set up. This is a great book for understanding where Italian Espresso is now, to get an idea of how it is seen and defined in Italy. There may be lots to disagree with, but there is also a lot of what we do put into better context.

Coffee History

Black Gold – Anthony Wild [Essential]

I will admit that this isn’t the liveliest book on coffee, and its approach to coffee trade and Fair Trade in particular are somewhat frustrating. To some extent it is a product of the time it was written in.

What makes this book valuable is the quality of research that went into it. This wasn’t a case of the author just spouting and regurgitating coffee’s history. Myths are debunked, accurate dates and events are given. This was particularly useful for me when trying to understand the real timeline for coffee’s spread across the globe – as both drink and crop.

Heavy reading but worth it.

Uncommon Grounds – Mark Pendergrast [Essential]

Very much a US-centric history of coffee, but nonethless still very interesting. Valuable again due to the quality of its research and the fact that the author came to clearly know and love his subject.

The Coffee-House: A Cultural History – Markman Ellis [Nice to have]

There are a number of good books on the coffeehouses of old – I also particularly like Anthony Clayton’s london centric one, as well as Ulla Heise’s more general book on European ones. This is a great overview, even if there is a little bit more detail in other texts. The coffee house society is something I find particularly fascinating, perhaps because I’d like to see a lot of that culture make a return!

Also recommended:

The Devil’s Cup – Stewart Lee Allen

Coffee – H.E. Jacob

Coffee Science

Espresso Coffee: The Science of Quality – Viani & Illy [Essential]

No great surprise here, but then no one has published anything that is both as broad and concise. A great wealth of information on coffee and espresso, from agronomy to roasting to tasting. And this is just the stuff the chose to publish – have no doubts that there is plenty they aren’t releasing. An amazing company, no matter what you think of the coffee. (Assuming you’ve had it fresh!)

Coffee: Recent Developments – Clarke & Vitzthum [Essential]

Following on from the Illy book, this is a pretty hardcore text but I consult it often when looking for specific research. It covers everything from instant coffee to espresso (though is woefully light on other brewing methods). It briefly appeared on Scribd but I think it has disappeared since.

Coffee Flavor Chemistry – Ivon Flament [Nice to have]

The title is at once completely accurate and slightly misleading. This book is essentially a reference text cataloguing the individual aromatic compounds found in both green and roasted coffee. It should be deeply boring, and I suppose it is. I am amazed, however, at both the range of compounds that smell similar as well as the baffling complexity of coffee. Sometimes the extra detail on how they identified which compound, or in which coffee it is often found is very interesting. If pictures of aldehydes sound like a terrible thing then this book is best avoided.

Coffee Volumes 1-6 – R.J.Clarke [Nice to have]

I spent a very long time looking for the complete collection of these 6 books, and if you see anywhere for under £300 then I would advise buying it for no other reason than it would be a great investment. (I am grateful to a blog reader who kindly sent me a link to a scandalously cheap collection). A huge collection of information on just about every aspect of coffee (the volumes are titled, in order: Chemistry, Technology, Physiology, Agronomy, Related Beverages & Commercial and Technological Aspects)

It is perhaps a little outdated, but I still find a great deal of valuable information inside them and I’ve barely dipped a toe.

Coffee Origins

Cafe De El Salvador, Land of Coffee [Essential]

I had to debate whether to put this one in under essential, but as it is my favourite book on origin then I think I have to. I am not sure of the best place to buy this – if anyone has a link please let me know.

I may be a sucker for El Salvador but I think this is one of the most beautifully photographed books on coffee growing, as well as the most detailed. It covers each of El Salvadors growing regions well – in a way that makes me wish I had a book like this for every producing country.

The History of Coffee in Guatemala – Regina Wagner [Essential]

Much like the previous book I wish there were one of these for every producing country.  The level of detail in the history of Guatemalan coffee is superb.

Brown Gold – Andrew Uribe C. [Nice to have]

This probably belongs in the rare and hard to find section, but I do think it is a great book. Written over 50 years ago it offers amazing insight into the world of coffee at that time. The photos are pretty amazing too, but you can ignore the recipes thrown in at the end – I assume they were to make the book more saleable at the time.

Look for Part 2 before new year.  Comments, recommendations or thoughts welcome!

These tips probably apply more to a commercial environment than a domestic one, but hopefully there are some useful reminders for anyone in here.

We’ve all ended up chasing an espresso, somehow a delicious espresso remaining elusive.  These may seem obvious but all get overlooked from time to time.

1. Plan for palate fatigue

Palate fatigue is inevitable, and too much coffee doesn’t just change and dampen your ability to discern flavours – it also quickly affects your enjoyment of coffee too.  David Schomer made a very good point once – coffee never tastes better than when your body really wants it.  We can often be a lot more forgiving of flaws when drinking that first cup that we really want.  The opposite is true for me also.  After too much coffee nothing tastes good.  When my body has had enough caffeine an espresso may be technically correct but I won’t find it delicious.  At this point continued tasting is not particularly useful.

Scott Rao recommends not just spitting the espresso you taste, but also rinsing immediately afterwards with water.  This is pretty much the best way I’ve found.  Drinking less coffee slows my caffeine ingestion, and the rinsing slows general palate fatigue.

2. Don’t overreact

Frustration dialing in a grinder often leads people to react too quickly to a bad shot.  Making sure that you’ve isolated the problem before making a change is very important.   All too often a shot will run fast and a barista will immediately change the grind a little finer.  The next shot runs too slow.  Double check before making a change, because everyone makes mistakes – an accidental underdose for example.

3. Purge

Even the best grinder in the world retains quite a lot of ground coffee.  Most visibly in the throat between the burrs and the dosing chamber, but also in the dosing chamber as well.  Every grinder benefits from a decent purge – 10g to 15g is plenty.  Consider it an investment in the next shot, rather than a waste.  Ending up with a dose made up from a mixture of grind settings is not a good thing.

4. Taste tells you everything

It won’t always point to the problem, but the balance of the espresso will give you a pretty good idea of what is wrong.  Unbalanced, dominant acidity coupled with astringency points towards underextraction.  It could be a number of reasons – pour too fast, temp too low, shot volume too short – but you can be pretty confident that you haven’t taken enough from the coffee.  An excessive, dominant bitterness and an unpleasant finish will usually point to overextraction.

5.  Take a broad sampling

When you are dialling in things like brew temperature this is incredibly difficult to do from only a few espressos.  Tasting more will allow you to get a better idea of what is wrong.  Little mistakes made from shot to shot can easily obscure bigger problems.  I don’t feel confident about saying a brew temperature is wrong until I’ve experimented with a number of other things first.

6. Have a strategy

Be methodical when working with an espresso blend.  Keep in mind that there are a number of different variables that we can change and work through.  Brew time, dose, grind size, brew temperature and shot length are the ones we would typically play with – though pressure is steadily gaining more attention (though I’ve yet to see any conclusive advice on using pressure to improve a shot.)

That said – feel free to abandon dead ends.  If you start with a 20g dose and no matter what you do it tastes underextracted/sour then increasing the dose is unlikely to fix that particular problem, so pulling shots at 22g or 24g may just be mean to your palate, rather than being a good way to use the coffee that you have.

7. Keep it clean

A dirty machine isn’t going to make good coffee.  It seems obvious but dirt builds up incredibly quickly in any espresso machine and it doesn’t take much build up before everything starts to taste disappointing.  Portafitlers, screens and blocks should be cleaned regularly and don’t be afraid of using chemical to clean often.  A coffee machine can’t be too clean!

I am not a massive statistics expert – and I am grateful to Vince Fedele for taking the data and cleaning it up and doing some analysis on it.

To start with the easy stuff:

Averages:

An interesting average espresso here – I would have suspected a slightly higher dose amongst readers of the blog, but a good number were dosing at around 14g for a double.  The average shot size was good to see.

Average ground coffee weight:  17.2g
Average shot weight:   32.7g
Average shot time: 27s

This shot would have a brew ratio of 53% – for those unfamiliar with brew ratios (credit to Andy Schecter) – Brew ratios. (Old post)

For those of you out there playing the ExtractMojos for espresso, or have been interested in espresso strength and extraction, Vince did a simple calculation where we assumed that extraction was around 20% of the coffee (as people had dialled in for taste) and therefore the likely strength of the average espresso was 12.2%.

This is very interesting to me because the average is pretty much where I have really been enjoying espresso recently.

Reasons behind recipes

I asked people to state why they used the recipes they did.  Here are the results:

A few surprises for me here:

Not many people use the roaster’s suggested brew recipe.

Flavour was a higher priority than texture.  This is only unusual because we’re talking about brew espresso, whose key pleasure (in my opinion) is texture.

One other reason I wanted people to answer these questions is so I could group them and then analyze.  One big surprise here for me.  I took the top three answers (flavour group, balance group and texture group) and looked at their averages:

Flavour:

Average dose:  17.5g
Average shot weight: 30g
Brew ratio (strength):  66% (13.6% TDS expected)¹

Balance:

Average dose:  18.7g
Average shot weight: 33.4g
Brew ratio (strength):  60% (12.1% TDS expected)

Texture:

Average dose:  16.7g
Average shot weight: 36.9g
Brew ratio (strength):  49% (9.9% TDS expected)

What do the above mean?  First off I was very surprised by the texture group – they pulled the biggest shots, from the least coffee.  Essentially they pulled the weakest shots (from which you’d expect the least texture).  I expected texture focused people to pull shorter shots from more coffee, and yet the results are the opposite.  The flavour group pulled the strongest, thickest shots and the flavour focused people were closer to the average (and how I like my espresso.)

Brew style:

I don’t mind admitting that I will have some preconceptions about how someone will brew espresso based on their starting dose.  Generally I would expect a shorter shot to come from a higher dose.  This has always seemed a little counter intuitive to me, because you have more coffee to extract so surely using less water will only make that more difficult.

I created a simple chart to see if my expectations were correct.  I charted starting dose against brew ratio.  This would mean that if people used more water with more coffee in a linear way then the data would essentially flat line.  This was not the case:

Click to embiggen

As I expected there is an increase in brew ratio (a decrease in relative shot size) with an increased dose.  However you can see the data is all over the place and there is a massive range of shots sizes being pulled from all doses.

From the above graph you can also see the distribution of the doses submitted in the survey.  It may seem strange to see a range from 7g to 24g.  The 7g entries were kept because the shot weight was clearly for a single espresso so didn’t affect the brew ratio calculation.

Summary

There is no right or wrong way to brew espresso.  However, I can’t help but feel this might be one of those moments where the wisdom of crowds has come good.  What I would appreciate is if the average espresso from the group is very different to your own – give it a try!  I’d love to hear your opinions, whether you found anything better from trying to pull a good shot using 17-18g, pulling about 32-34g of water through it (brew on scales) and aim for about 25-28s.  Let me know if you try it!

If I was going to do the survey again I would probably add a few more questions, and I hope to do another survey soon – perhaps about brewed coffee, or maybe espresso again.  Your thoughts welcome.

1. Again – to clarify:  I couldn’t get people to measure the strength of their extracted shots, so it was assumed that if they tasted good they were extracting approx 20% of the ground coffee into the cup.  Essentially this is something of a guess.

Something about this just doesn’t sit right for me. I am going to assume that if you are reading this then you probably clean a coffee machine the same way that I do: portafilters regularly scrubbed and immaculate, screens dropped and scrubbed clean, dispersion screw kept clean, group seal cleaned and dispersion block scrubbed clean. After all this we do run the backflush routine with a small amount of chemical.

For years I did the backflush bit wrong. ¹  These days I find the routine on the side of a bottle of Full Circle the best explanation and method. ²

Now as I understand it we are really trying to clean a small section of tube that runs between the solenoid valve and the dispersion screw. ³  This tube gets dirty because coffee travels up it during the pressure release at the end of pulling a shot when the solenoid opens up.  As such this tube can get a build up of unpleasant flavours.  This happens very slowly – compared to how quickly the dirt in a portafilter builds up and ruins a shot.  Flushing in between shots probably helps slow down the build up in the tube.

So when we backflush we switch the group on two pump in water to dissolve some chemical and then switch the group off, the solenoid pressure release sucking the chemical up the tube where it can start to strip off any build up.  We repeat this process to ensure thorough cleaning and then we go through a rinsing process.

I think we all agree that at this stage there is no chemical left behind, and if there were it would be a specific and unpleasant taint to the next shots.  However we are told that the next shot will taste bad regardless.  I would like to suggest that this bad taste is primarily due to a loss of heat at the group, affecting the brew temperature and creating an unpleasant underextraction.

First of all – this piece of information is pretty much written in stone but how many of you have tasted the next shot out?  Exactly how did it taste bad?  Very few people have tasted it because they are always told it is going to be bad, so why would you?.  Those of us that have have probably done so in one of two scenarios:

1).  Tasting immediately after a backflush.  Here the group has likely cooled down, because very little water has moved from the boiler out of the front of the group.  On some machines this may influence the brew temperature.   Plus we’ve left our portafilters out for a while and I would contend that the first shot you brew will be under temp.  We may have gotten into the habit of using that shot to bring the group and portafilters up to temperature, because we know it is a wasted shot regardless. ⁴

2).  The next morning.  Here the group has again cooled down due to a long period without water travelling from the boiler to the dispersion screen, and the shot would likely be undertemp.  If you leave a stock Linea alone for 30 minutes during the day you need to flush a lot of water through it to get it back up to maximum, stable brew temp.  What if you left it 8 hours?

In both cases it is somewhat likely that the poor taste of the shots could be primarily attributed to brew temperature.  I asked Josh Dick from Urnex this very question during our Barista Magazine article and there didn’t seem a more likely explanation.

I have a Synesso Hydra.  From leaving the pump to hitting the coffee the water travels through a good deal of metal piping.  Are we seriously suggesting that while it will pick up no metallic taint from the majority of its journey, but if a small tube near the coffee is not coated in coffee oil that it will somehow have a massive impact on taste when the rest of the machine’s metallic surface will not?  If that tube is dirty then I absolutely believe that it will have a negative impact on the shot, but too clean?

Last night I did a very simple experiment.  I chemically cleaned my machine, and left chemical in it for well over 2 hours.  I want it as clean as was possible.  This morning I dialled in the grinder on the left group, and once happy I then flushed the right hand group up as hot as I could.  Once I was satisfied that it was hot enough I pulled a shot and I drank it.  The seasoning shot.  Did it taste bad? No. Did it taste sour or metallic?  No. Could the fact that it was my first coffee of the day have influenced me? Absolutely.

However – lots of you reading this have coffee machines.  Lots of you probably have Scace devices.  I am absolutely happy to be proven wrong but I would just like to get to the bottom of this phenomenon.  How do seasoning shots taste to everybody?  Do we all agree on what is wrong?

1. I would put chemical in, switch on the pump – assume that this part was the cleaning part and let is run for 30 seconds and then just rinse everything clean.  A complete waste of time.
2. By the way – given the choice between Cafiza and Full Circle is anyone not opting for the sustainable option?  It may cost a little more but surely the tiny cost increase per backflush really doesn’t matter.
3. If I am wrong here – I am more than happy to be corrected!
4. I accept that on some machines backflushing and then immediate brewing may result in high/higher brew temperatures, but rarely are people pulling shots immediately afterwards – usually there is sufficient time for that extra heat to dissipate.

Brew recipes have been on my mind again recently, so I thought I’d post up this quick poll.  I’d love if it people could give me some data on this.  If enough people respond then I will post up the results, and any trends that occur.

A few quick things.  Please dial your espresso in to the point that you are happy.  It doesn’t need to be godshot territory, but something you’d serve to a customer or friend who you liked.

Secondly – please weigh things properly.  A lot of people speculate the weight of ground coffee they use, and very few people are accurate with it.  The more accurate the measurement the better.

Just to emphasize this because it is important – I need the weight of your shot not the volume.

Once you’ve weighed the shot feel free to drink it, to make sure it tasted good.

Here’s the poll:

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These last few days have been a pleasant, but steep learning curve.  I know I’ve muttered about pressure profiling from time to time, but I hadn’t really played with a lever machine properly until Gwilym’s WBC prize arrived. ¹
I am not quite at the popeye arms stage yet, but I could see how you could incorporate a machine like this into a serious workout routine.  I have had some delicious shots, but I have had to abandon the traditional time frames I have used for espressos I know well.

Lots of little things make an impact.  The size of basket has a very strange impact – keep the dose the same, but have a bigger basket means that more water fills the chamber above the coffee meaning you will pull a longer shot.  Changing basket but keeping the dose the same has enough of a weird impact using my Cyncra, but this one single variable has a terrifying domino effect on the shot!

Gwilym came by today, he’s on his way to Italy to visit La Marzocco and wanted to pick up some coffee to play with.  We thought it would be fun to pull some shots of the same batch on the Athena that he’ll play with out there.  The impact of even tiny adjustments to pre-infusion time made an astonishing difference to the cup.

As you can see from the photo above I dug out my Gaggia naked portafilter, as I was curious to see what effect the lack of dispersion screw would have.  (This is the first machine I’ve used without one).  Turns out it is nothing noticeable, but then I am not sure how much detail can really, really be discerned from a naked portafilter.  They do still look pretty though.

Shot times appear to have gone out of the window.  Or at least the window has moved quite substantially.  People who go to Naples often seem to come back remarking on the 45 second shot time.  I haven’t had much under 35s that I’ve really liked, though I haven’t played much yet with barely any infusion so that may change things. ²

Now I’ve never been one to worship at the altar of crema, I don’t want more of the stuff, I don’t read too much into its texture or its colour.  However from an aesthetic point of view the shots from the Athena do look remarkable pretty.  Darker espresso roasts than ours mottle/tiger stripe in a wondrous manner (had some very tasty shots of Espresso Rustico from Counter Culture which I wished I had photographed because I think they’d be an interesting reference point for barista competition judging).

I can’t quite put my finger on exactly how the shots change.  I also admit that I’ve had more experience than most with pressure profiling, and the impact of soaks and ramps.  I do know that you can get some very interesting textural and taste based results (I am separating taste from flavour here), but I also know what a knife edge it can be.  I’d love to pull a few hundreds shots on one of these and see how you build a workflow around them, would it lull you into a pleasant and soothing rhythm or taunt you with its crawling pace.  Plus if you pull a choker then there isn’t much you can do except be patient. ³

I consider myself very lucky that Gwilym has kindly let us play with it.  If you are coming to roastery any time soon then I’ll probably try and force a shot or two onto you and talk in an overexcited way.  I am aware this post comes off the back of a post about how silly espresso is, and how we should all love brewed coffee, but from a personal point of view it is rare that I get the opportunity to go through a learning experience like this one.

I’ll try and post more about it all as I learn a bit more and have something solid and interesting to say.  If you have experience with lever machines then I’d love to know your thoughts.  If I have one gripe with the machine (and this is exceptionally churlish, considering I am borrowing a friend’s prize) it is that the cup tray is really quite tiny.  Petty?  Me?  No….

1. Yes, we kindly offered to ‘look after’ it for him for now…
2. For the record I would start the time the moment the lever is sufficiently pulled down that you can hear the water entering the brew chamber.  Other than that it is noticeable how eerily quiet the whole process is.
3. I have been told a couple of methods to interupt the brew, but frankly they either scare me or increase the likelihood of me making a mess of my clothes and I just can’t condone those things.

As always the paricipants there were way smarter than me and offered several interesting options. I dropped into the thread that this was part of my idea of a grand unified theory of espresso, and subsequently a few people mailed and pm’d me asking what on earth I was talking about and what density had to do with it.

Well, I should probably explain what I have been thinking. ²

When approaching a coffee and brewing it using an espresso machine you are often searching for an ‘ideal’ recipe for that coffee.  For many of us knowing as much about that coffee as possible often helps make intuitive judgements about things like dose and brew temp.  If I get my science wrong then please, please shoot me down. ³

One of the things that broke my head about roasting early on was the discovery that the longer/darker you roast the less potential solubles you have.  This may seem obvious to some but it always felt like the roasting process created many new flavours but one must distinguish between flavours and solubles.  This explains why instant coffee is roasting very fast and relatively light – they are interested in a percentage yield so the more solubles the better, regardless of taste.

Knowing this then made something I had experienced make apparent sense – darker roasts generally prefer higher doses, because you need more coffee to get more solubles to get a nice, thick and pleasant espresso.  But after a moments thought it didn’t make sense.  This would mean that you would get a thicker, heavier cup with a higher TDS measurement from lighter roasts but lighter roasts generally produced delicious but lighter bodied cups.  What nudged me towards density was how we approach very high grown coffees versus lower grown coffees.

Higher grown coffees (and let me make a broad sweeping generalisation here) have a much higher acidity than their lower grown brethren.  When brewed as espresso they can easily yield extremely acidic and unbalanced cups and, taking unbalanced and pronounced acidity as a sign of underextraction, I found that higher brewing temperatures helped to produce a more balanced cup.

What do lighter roasts and high grown coffees have in common:  higher densities.  Though there was more to extract (in theory) you had to work a lot harder to do it.  Therefore reducing the dose of a lighter roast/higher grown coffee gave you a higher ratio of water/energy to coffee to help extract a tasty cup.  (I often think of heat energy as some sort of currency, with which you can buy solubles.  The more heat, the more you extract/purchase.)

This is all well and good for convenient examples – high grown, light roasts versus low grown darker roasts.  Give me a clean prepped coffee from relatively low altitudes in Brasil, roast it into 2nd and I will likely be dosing quite high and not brewing too hot.  I’ll certainly be dosing it very different from how I might brew a lot of Aricha as a straight shot.

But what about a light roast of a low grown coffee, or a dark roast of something grown super high up?  This is what lead me to wanting to find a way to measure and compare the densities of coffee beans to see if there was correlation between the density of the end product and an ideal brew temperture of particularly effective dose.

So – if I have had such a good idea why don’t I do all the research and then publish it all at the end of it and try and stamp it “Hoffmann’s theory” or something equally absurd? (Apart from the fact that it is absurd).  Because I want to generate a little discussion about this.  I want people to weigh in and tell me I am being stupid/simplistic and to suggest better ways to test these ideas.  I want to understand espresso better so I can make better tasting drinks and translate coffee’s journey more transparently in the cup. ⁴

I really hope people will offer their opinions on this idea, shoot it down or take it and run with it.  I am going to start doing some basic testing and see what happens.  Lots of little experiments appeal. ⁵

1. There really is no better place on the web for these kinds of questions!
2. Some of this is based on personal preference, some on what seems to be fairly well agreed upon within the community of people who worry a lot about their espresso.
3. There is another post in the works about the value of being wrong and discussing it afterwards – yes, I have a big wrongness to confess to…..
4. I know this is a wordy post and all, and I would have put some nice photos in but my camera is dead
5. For example – if I roast two coffees til their densities match – will they grind the same, and at the same dose will they extract the same?  Would they be ideal, therefore, to blend together to get the most out of each of them.  This probably shouldn’t be a footnote, but it is.  So there.