Tuesday, 17 May 2011


It's off to Indonesia for me, for three weeks.  It's a backpacking holiday and we (my wife and I) don't really like to plan hols too much, so I'm not quite sure where we'll end up.  But we're definitely going back to Bali, and very probably hopping across to Komodo, Rinca and Flores to get away from it all. 

We've spent a fair amount of time on Bali previously - probably over a month in total spread over a few trips.  Coffee never featured in those trips at all, so the fact that my growing obsession with coffee has opened up a chance to do something new on our holidays is a big bonus.

The Munduk area where the plantations are looks a little remote, hidden underneath the far side of a few volcanos.  It's certainly not a touristy area (thankfully!).  It can be too easy to langiush in the tranquility of Ubud and miss the surroundings, so it will be good to see a little of the real Bali, as well as hopefully learn something about the lives of the people who work in the plantations.

Should be good for a day or two, before moving on to Komodo for a bit of diving.

Monday, 16 May 2011

AeroPress with Hario Mini Mill hand grinder

NB After reading this blogpost you may like to read a follow-up post written over a year later. See here.

I got a Hario Mini Mill hand grinder recently, because I've decided to keep my Gaggia MDF grinder just for espresso. Changing between an espresso and a drip or press grind used up quite a lot of beans to get it working right. So the Mini Mill is just for non-espresso brew methods.

So now I need to work out what grind settting on the Mini Mill works best for each brew method. Here's a little picture of different grinds. Unfortunately the preferred AeroPress grind isn't mentioned but I believe it is slightly coarser than espresso.

There are actually no visual settings on the grinder.  You just turn the nut and feel it click as each setting slots into place.  But I'm taking the approach of starting from a completely 'closed' position (i.e. the finest grind), then counting back the number of clicks from there as I turn it anti-clockwise.

So today I tried the following on the AeroPress:
Beans: Columbian Excelso Bucaramanga Municipality, from Coffee Chocolate & Tea in Glasgow
Days since roasting: 18
Grinder Setting: 3 (very fine)

I also pressed the AeroPress all the way down, rather than stopping (as I did last time) once I heard the hissing sound.  This brought the crema-like foam through the filter and into the cup.

The resulting coffee was strong and very bitter - not at all what I'm looking for from the AeroPress.  Typical signs of over-extraction, so I reckon the grind was too fine.  I also decided to ditch the idea of allowing the crema-foam to enter the cup, as I'd imagine it is filled with bitter compounds.

I tried again, this time increasing it to setting 5.  The coffee was less bitter, and the flavours of the bean did start to show themselves, but still too strong and not sweet enough for my own palate.

I read THIS thread on the coffeegeeks forum, and two posts are saying that 6-10 clicks is the right zone.  I'll therefore try 8 next time and then update this blog post.

1ST UPDATE: 8 clicks ... I'm drinking it right now... Still no sweetness, but the strength has evened out to an acceptable level.  Actually I think that what I'm tasting now is acidity rather than bitterness.  Yes... it's cooling now and there's a tart, lemonjuice taste coming through.  OK, I'm thinking maybe I've found the right grind setting for AeroPress (8-ish), but I'll try a 10 just to be sure. 
I'm struggling a little with this.  I'm going to try different beans anyway just for peace of mind.

2ND UPDATE: 10 clicks.  Much better.  I also changed the beans to Formula 6 by James Gourmet Coffee, an espresso blend.  Strong (moreso than drip coffee), balanced as I might expect an espresso blend to be.  I'm not good at picking flavours out yet, so I'll cheat and have a look at the roaster's comments:
"I am finding that with our F6 cappuccinos you can get great toffee and caramel notes with nuts lots of milk chocolate right now.The shots are strangely sweet, fruity & rich with great body."
Yeah, although it's not brewed as espresso I can still get a recollection of a fruit taste, like some kind of sharp berry but without all the sweetness of the actual fruit, like I get when I bite into a blueberry. But maybe it's in my mind.
Anyway, approx setting 10 on the Hario Mini Mill for AeroPress brewing.

(By the way my Hario arrived without English instructions.  Here are some dual-language instructions I found online.)

*** EDIT: 23 Feb 2012 ***
I can't help noticing that this post has been linked to on a few sites and read by quite a few people. I'd therefore just like to update it with some more recent findings.  I've been using setting 5 on the Hario Mini Mill, which increases the brew strength, but to compensate I've used cooler brew water, specifically 80 degrees C, using a brewing ratio of around 1g of coffee to 15.5g of water.

Thursday, 12 May 2011

More on the hunt for The Perfect Espresso

Following on from my last post, I’ve spent two or three days actively working on finding the best combination of parameters to produce as close to the perfect espresso as I’m capable of right now (notwithstanding various limitations outside my control).  The perfect espresso will always be a subjective thing, so my aim was to find the settings that suit my own palate.  In essence, I’m looking for the ‘brew recipe’ that works for me with the beans and equipment I’m using.

Before I explain more, I’ll just jump forward and say that this little experiment has yielded a huge amount of learning for me, someone relatively new to espresso.  I now know more about the type of espresso shot I like, how to make it, how to taste espresso, how to identify and describe what I’m tasting, and a few things that I now need to do next.  I’d recommend anyone who wants to improve their espresso to go through this simple process. As it involved mulling over your thoughts on the espresso shot, I’d sum the process up with the catchy phrase “Don’t just drink it, think it.”  Ahem...sorry about that bit!

OK, so, I wanted to make use of brew ratio (aka brewing ratio), which is a measure of the amount of liquid espresso produced in relation to the dry beans used. For example, if you use 14g of beans and end up with 28g of espresso, your brew ratio is 50% (also sometimes shown as 1:2).  Andy Schecter started an interesting post (see here) on Home Barista about it in 2006, and one of its proponents is James Hoffman (World Barista Champion).

As mentioned above, this involved weighing the amount of coffee before and after extraction.  Using weight (g) to measure the amount of espresso produces is arguably a more accurate approach than using fluid ounces (oz), because crema makes the true volume in oz very difficult to measure.  Therefore, rather than... or indeed as well as... talking about a 2oz shot, it can be more useful to use terms like a 30g shot, and a 65% brew ratio. 

It isn’t a new approach, but as Andy alludes to in his post it seems that many of us are reluctant to make the switch from using oz to using weight and brew ratios.  Maybe we feel comfortable with what we know, and see no reason to change.  My own feeling is that brew ratios provide the key to another door on the quest for the perfect espresso. It’s up to the individual to decide how many keys they want to collect, and how many doors they wish to open.

It took me only 9 shots, spread over 3 days, to identify the parameters that I like best.  I had my laptop open next to the espresso machine, and after each shot I scored the espresso based upon flavour and mouthfeel, and made comments and suggestions for how I might make improvements in the next shot – i.e. changes to parameters – in an effort to home in on the ‘sweet spot’.  A screenshot of the Excel file I used record the findings and calculate the brew ratio is shown below.  Each row represents a different shot and my findings/comments.

As are many parameters in making espresso, and changing any parameter will have an effect on the other parameters, there is no single correct approach.  But here is the one I followed.

Constants, limitations and assumptions:
1. Initially, try to keep all the parameters fairly constant except one – pre-grind dose weight.  As you get towards the latter stages of the process, you can start refining other parameters one at a time.

2. I used the same bag of espresso blend beans throughout, and of course if I use different beans in future I would expect the parameters to change.

3. I am currently unable to measure or accurately control brew temperature with my Gaggia Classic.  I therefore attempt to ‘temperature surf’, to provide a degree of temperature stability throughout the brewing process.

4. I do not have large enough scales to measure the weight of grinds in the portafilter before extraction.  I therefore base my pre-extraction weight upon the weight of the pre-ground beans.  As each bean tends to weigh approximately 0.8-0.12g, and I do not expect to lose more than 1 bean in the grinding process, I assume this approach is accurate enough for my purposes.

1.       Select an initial brew time, and keep that constant for now.  All extractions should be stopped on (for example) 24 seconds.  There will be a chance to adjust this later.
2.       Select a grind and keep it constant for now. Again, refinements will be made in due course, but by keeping this parameter constant you are able to work on refining the shot using other variable parameters.
3.       Select a range of Pre-Grind dose weights.  I chose 14g to 20g.  You are going to start with the lowest dose for your first shot, and move up the scale.  Dose is your primary variable parameter, at least initially.
4.       Weigh, Grind, Dose, Distribute and Tamp your first shot.
5.       Fit the portafilter into the grouphead and place scales on the drip tray. Put a shot glass on the scales and tare them to zero.
6.       Start the extraction. Begin your timer. 
7.       As the shot pours, watch it.  Notice how fast it extracts. Is the flow diameter thin or thick.  Is there any blonding, and if so when does it occur? This info can all be useful in your tasting notes, and inform your ‘suggestions for improvements’ in the next shot.
8.       Stop the shot at your target time.  Give the shot a few seconds to let the weight stabilise.  I take the glass and scales off the drip tray after about 3 seconds, and give them another 3 on the table before noting down the weight.
9.       Time to start assessing the shot.  First, it is worthwhile noting what you think is the approximate volume in oz, just to tie the data in with the way you previously measured it.
10.   How does it look? How does it taste? What is the mouthfeel like?
(a) Here is a good link for non-coffee-geeks on how to taste espresso. It's worth taking the time, if you're not used to thinking about and describing what you're tasting, which I'm not!
(b) The Coffee Tasting Flavour Wheel.  Have this open on your computer.  This part really involves thinking, not just drinking.  Look at the wheel and see if you can identify any of the tastes/aromas.  My palate is terrible and I’ve never before been able to pick out things like sweetness, or acidity, or tartness, but going through this process has been a revelation and as you can see from my comments, I’ve started being able to pick out some of these.

Write down your scores (out of 10) and your tasting comments. 
Do you like this shot.  If so, notice the brew ratio. Are you tending towards a preference for Ristretto (100% brew ratio), Normale espresso (approx 40%-60%), or Lungo (33%). It’s good to know your own tastes.
Reflect upon your comments.  Look at the data.  Try to understand why it is something may be the way it is. For example, look at my 16g shot.  I saw ‘Tart’ on the flavour wheel, and also that it is part of the Sour range.  I’ve read that Sourness can come from low brew temperatures, so I made a note in the column called “suggestions for improvement” to try to improve my temperature surfing in the next shots.  I did so by flushing 2oz of water through the group head, 2 or 3 times, with a few seconds gap inbetween each burst, just before fitting the portafilter. 
11.   OK, time for the next shot incorporating one of your suggestions.  Don’t make lots of changes all at once. Remember, we’re trying to keep as many parameters constant as possible.  So, increase your dose from 14g to 15g, and if you are able to make other improvements without feeling like you’re significantly changing the balance of the brew parameters, do so.
NB: Really try not to change the grind setting in the early stages.  Changes in the dose will effect the flow rate of the shot, so you may find that a fast flow slows down as you updose.
12.   Go through this cycle a few times, increasing the dose each time.  Eventually you will get a feel for the pre-grind dose and brew ratio that is working best for your own palate. Now you can start to refine other parameters.  I recommend starting with time and leaving grind for now, unless it’s clear to you that the grind is just not right. So, if you find that the shot tastes great but there is just not enough of it, try changing the brew time from 24 seconds to 25 seconds and see how it tastes. Maybe this will result in a more bitter shot as more of the compounds from the bean are extracted.  If this is not to your liking, then stick to 24 seconds, but now you can try changing the grind.  Try making it coarser, to allow more water to flow through the grinds. Now pull shot and make your tasting notes. Not right for you? Perhaps you should actually have made the grind finer, allowing more solids from the bean to enter the espresso.  Change the grind, pull a shot, and make your comments.
13.   At the end of this process you should have identified one shot that scores higher than the others.  You may also have found out some of the limitations of your equipment or indeed your skills.  For example, I was unable to produce a shot that I liked greater than 25-28g (approx 1.5oz).  Coupled with that, I found it difficult to pick out individual flavours or varietals within the espresso (which may be due to my inexperience, but also may not).  Both of these are symptomatic of dull grinder burrs, and since my 2d hand flat burr grinder is 5 years old, it’s a safe bet that it would benefit from new burrs.  This would increase the amount of good espresso yielded during the brewing process.

So there you have it.  I’m not claiming to have invented anything here, not by any stretch of the imagination.  All of this comes from reading the work of other gifted people and putting it into some sort of process that I can follow in my own OCD manner!  Since I couldn’t find a step-by-step approach already documented anywhere online, I’ve written one in the hope that someone else might benefit from my messing about with espresso!  I’m not claiming that any of it is correct either.  Please feel free to disagree or challenge, or indeed add to and enhance this approach.  I’d love to hear your own experiences of using brew ratios.


Monday, 9 May 2011

The Holy Grail - Espresso

Over the past few months, since getting my Gaggia Classic, I've made at least 4 double espressos every day, most of which have then gone into a latte in a bid to (a) give my wife something to smile about, and (b) improve my milk steaming and latte art abilities.

Recently I hit a stumbling block when I bought some fairly 'challenging' beans from a local roaster and just couldn't get a good espresso shot from them. After posting on coffeeforums and changing brew parameters I managed to get an acceptable extraction, but it got me thinking that I still have a lot to learn, and it's easy for a beginner like myself to fall into the trap of think he's cracked espresso when really all he's done is gain a fairly superficial skills in the mechanics of pulling a shot, without truly understanding the nature of coffee extraction. Why would the latter be important? Because (amongst other things) if your understanding of the science behind the shot is limited then you won't know what to do when something doesn't go according to plan, as I found out with my challenging beans.
- Should you updose?
- Downdose?
- Grind finer/coarser?
- Is your brew temperature too hot/cold?
- Are you over-extracting? Under-extracting?
- What do over- and under-extracting even really mean? Are you sure you know?

Do you even know what questions to ask yourself? I realised that I didn't.

On reflection, I think it's part of the natural evolution of a barista-in-training. I'd liken it to someone learning to ski. You simply can't be taught how to ski off piste the first day you put the skis on. You have to learn the snow plough first. Eventually you have to unlearn the snow plough, but it's a good place to start. There's a sequence of events that you take to learn. It's not the only way, but it works.

Similarly with learning to extract espresso. At first you're taught basic parameters such as:
- 7g for single shot
- 14g for double
- Tamp with 30 lb of pressure
- Extraction should complete within 18-23 seconds of the first drops appearing
- A single shot is 1 oz
- A double is 2 oz

Then as you develop, you get involved in discussions with other baristas. You learn new things, some of which contradict what you've already learned, such as:
- Most people don't pull singles
- Most people use most than 14g for their double shots
- Many people talk about the perfect '30 second extraction', counting from when they start the brew rather than from first drops
- Others don't use time to dictate when the shot should stop. They rely on visual cues, like watching for when the flow starts to turn blonde.

So you absorb all of this, which I did, and you notice improvement in your shots. But is it enough? I've found that I'm still keen to learn more.

So I've recently read a few more things that have really piqued my curiosity. Gentlemen such as Andy Schecter (who's every written word has hugely impressed me) and James Hoffman were talking about Espresso Brew Ratios way back in 2006. One of the key tenets of using brew ratios is that due to the existence of crema you can't accurately see how much espresso has been yielded by an extraction. Using fluid ounces, a unit of volume, is fundamentally flawed because the volume varies depending upon bean freshness and crema production. Using grammes to measure both pre- and post- extraction is arguably a better approach.
Here are some links on this subject:
Home-Barista forum discussion
James Hoffman's Blog

So I'm keen to start weighing my espresso shots. This isn't something I'd envisage doing if working in a cafe environment (but you never know!), but I think it will help advance my understanding enornously.

For a start, just by reading the above I've learned a few new phrases. I'm finding that these definitions, like many things in this arena, are subject to debate, but here they are:
TDS (Total Dissolved Solids) is a measure of the amount of solids that pass into the resulting espresso from the ground coffee beans.
Extraction Yield is defined as "mass of coffee solids in the beverage divided by mass of original dry coffee dose".

I've also established that presumably there is a 'preferred' TDS value for espresso, based upon empirical research and experimentation over the years, possibly by the SCAA.
Also that the SCAA 'preferred' extraction yield is 18-22%.

Now we're getting scientific, which is definitely helping me. I know that ultimately it's all about personal taste, and no scientific formula can guarantee a good expresso, but I reckon that understanding these elements of the equation can only help.

So what's next? Well, in my view I still only have a fairly superficial understanding so I need to keep reading and experimenting. My plans include:
1. Today I've received "Espresso Coffee: Professional Techniques" by David Schomer. I think it will give me more than a solid foundation in espresso, if 3 months of reading forums has not already achieved that.
2. I'm going to run a series of tests, pulling espresso with constant and varying parameters for pre/post shot weight, extraction time, resulting brew ratio, and in the absence of having a refractometer to measure Extraction Yield and TDS I'm just going to use my gob, and taste it. I hope I'll get several things out of this. An improved coffee palate for one, a better understanding of the extraction process, and an opinion of where my own preferences lie with regards to espresso brew ratios. In 2009 James Hoffman ran a poll of just under 100 people to capture details of their espresso preferences.

If the average preferred brew ratio is 53%, where do I sit?

Anyway, time to stop gassing and get on with it! Thanks for reading today's hefty post!!

Thursday, 5 May 2011

Success with the AeroPress, and a revelation.

I've been reading/watching guides to brewing with the AeroPress and finally got the balance right. What has surprised me is that I couldn't get a good extraction following the methods used by some of the popular/credible coffee geeks, and ended up getting the best results after watching a video by a pregnant American housewife called Tammy who got one for her birthday!

I did modify the method a tiny bit based upon what I'd seen on other tutorials.
(a) Tammy keeps plunging until all the foamy gunge, which actually looks like it might be a kind of crema, is in the cup. I stopped before then, once I started hearing a hissing sound. I looked and did see the 'crema' but it went in the bin with the grinds. Next time I'll try tasting it.
(b) I also didn't use the scoop. I used 20g of fresh beans (an espresso blend), ground slightly coarser than I would for an espresso.
(c) With the 20g in, I added water up to the number '2' marker. It was great to see the grinds start blooming immediately.
..oh..(d) before brewinhg I rinsed the paper filter thoroughly with boiling water to remove any potential bleach taste.

Stirred for 10 seconds, plunged for 20 seconds and....
what a revelation! I got about 4 or 5oz of VERY good coffee. Really. There was no hint of bitterness or acridity. Pure, smooth, no need for sugar etc. I didn't add any more water to dilute, as it wasn't needed. I tried it on my wife Jan, and she agreed it was 'nutty' and much better than my previous attempts at brewed coffee. The secret did seem to be using less water. 'Nutty' indeed! I tried it, and I suppose I could understand what she meant. It did somehow have a hazelnut ring to it. Meh...

Very pleased anyway. Thanks Tammy! Watch your back, James Hoffman, she's good! ;)

Next time I'll up the dose and volume to see if I can get 2 cups working well.