One of the questions I'm often asked when training new recruits or chatting to people about my job is what actually qualifies me to be Head Barista over a standard barista. Whilst there are a number of ways I could answer this question, ordering coffee, promotion or training; the answer I invariably go for is my ability to dial in coffee and keep the grinders dialled in throughout the day to make the most out of a blend. In the long and complex route speciality coffee takes from the coffee plant to the final consumer, the coffee grinder is one of the last links in chain, and with that comes a huge weight of responsibility to make the most of an amazing coffee.



In this article I'm going to talk about how I dial in coffee in a coffee bar situation and keep that coffee dialled in throughout the rigours of a busy shift. I also want to talk about how you can take a lot of what I have picked up in coffee bars and use it at home. I'll provide tips to make your home coffee brewing faster, more efficient and above all, get the most of the (hopefully) amazing coffee beans you'll be using.



One of the first steps of any shift in a coffee bar as Head Barista is to dial the coffee in. This is either from scratch to get it ready for shop opening or at the start of a shift to troubleshoot and make sure all is well in the world of coffee. Dialling in from scratch means you're using an espresso machine that has been left clean overnight. It's always important to follow a few steps before you pull out the most important of barista tools: the pocket scales.



The first step is to purge through a shot or two of coffee. This is a great time to pull a blank shot through the machine and leave the used coffee puck in place for a few minutes or so to help the group come to and maintain it's operating temperature. Whilst pulling this sink shot however, it never hurts to keep an eye on how it's pouring and how big the dose is from the grinder just to give you a few basic starting points to dial in your grinder. Bear in mind that, at least from my experience, sink shots tend to pour slightly slower than the following shots. I imagine this being due to some of the crema/oils being held back by clean, unseasoned metal though I can't be sure.



Once your sink shot has been pulled and some coffee has been purged through the grinder, it's time to start your dialling in. As I mentioned above, this is nigh on impossible without what I, and many others, consider to be one of the important tools in any barista's inventory, a simple set of pocket scales. You can pick up a set of these for less than $20 and they will instantly improve your coffee pouring prowess, efficiency and wastage ten fold.



Now if you're dialling in your grinder from scratch and you can't remember the ballpark setting for espresso, a simple way to get close is to adjust your grinder until the burrs are touching and then pull them back a few notches (or whatever increment you use to adjust your grinder). This should give you a fair estimation of an espresso grind.



When it actually comes to dialling in the shot I used to lazily guesstimate two interconnected variables at the same time: grind size and dose weight. As any of the methodical amongst you will know, this is a bad idea as you can easily get into a cycle of swinging between the dose being correct, the grind size being correct and yet still have not dialled in the espresso at all, a great way to waste lots of delicious coffee as well as a good chunk of mental stability. Weighing the Dose

Weighing the coffee dose has become one of the standard, and very crucial tools used by baristas to deliver the best espresso

My new method is one I imagine most shop baristas use; get the dose size right first. If you have a timed grinder with an ability to purge as I do at my shop then I find it easiest to way the dose straight into the basket and adjust it before I set the timed dose on the grinder. This way I don't have to mess around adjusting the the timer before I change the grind which could throw the dose off again.



Of course some cafés do not use grinders with timers and many home baristas won't have the ability for a timed dose, so a simple way is to weigh out the amount of beans you want and weigh them again once ground to ensure that the grinder hasn't held too much back as almost every grinder will.



Once your dose size is right in the basket, tamp it and get it pouring. Try to keep the process of grinding and dosing as fast as possible because if your portafilter/ basket loses too much temperature, you run the risk of pouring a sour shot. This can throw off your ability to correctly diagnose flaws in the final shot.



Now comes the second chance for you to use your scales. Weigh the espresso. When I started in coffee, this wasn't really common practice. Now it does seem pretty ridiculous that it wasn't as it's a more consistent and repeatable way to measure and record the yield of your espresso shot. Just think about the difference in volume of crema between a coffee two days off roast to a coffee a couple of weeks off roast.



Of course, whilst you do all this weighing, it's rather useful to have a base set of figures to aim for, a simple recipe for your espresso. You will often be able to find this on-line, or ask other baristas for advice on this. Failing this you can go for a relatively generic recipe, 19g dose yielding 28-30g in 20-30 seconds being a fair start. If your shot yield is totally off within this time frame, then comes the chance to adjust the one variable you should be left with, temperature of the machine aside, grind size.



Put in its' most simple terms, a coarser grind will yield a shot that pours faster and a finer grind will yield a shot that pours slower. At this point, it becomes very handy to know your grinder, though if you don't, this article should give you a good base to start learning.



Depending on the sort of grinder you're using, the two most common methods are stepped or stepless. The stepped version gives you fixed increments of adjustments, and stepless giving you a finer control. However, even if you are using a stepless grinder, it's always handy to have your own set idea of an increment of adjustment, as this will aid you in remembering how much one increment of adjustment will change the shot and dose size.



A couple of things to learn or write down is how much one increment change adjusts the dose size. A finer grind will grind slower, yielding a lower dose. Note how much it changes the time of the pour for your intended yield. Having these two figures in your head will enable to you be as efficient as possible in dialling in a shot with minimal wastage and time.



You can now adjust your grind, whilst maintaining the dose size, to get your espresso within the parameters of your recipe. Now comes the fun part; tasting, tasting and more tasting! Chances are that your shot won't taste too bad as long as your machine is clean, beans are good quality and fresh, yada-yada, but what you're really wanting to look for is certain signs that you can control through tweaking the recipe you've chosen.



If you notice a lot of sharpness or sourness in your shot (think lemons) then there's a good chance it's under-extracted, meaning there are not enough dissolved solids in the shot. This can be caused by the shot running too fast with a reasonable shot volume or the shot volume being too low but in a reasonable time . It can also be a potential sign of channelling, allowing water through parts of the coffee puck too fast.



Channelling looks like pencil lead sized holes in the spent grinds or around the edge where it has pulled away from the basket. There are a few ways to resolve this problem but most often it can be solved by focusing on distribution and tamp. Often light tamps can result in a higher likelihood of channelling as well as poor distribution before tamping.



If you're getting the opposite end of the spectrum with a lot of bitterness and a generally dull espresso, chances are you're over-extracting the espresso and pulling in a load of undesirable solubles. This is normally caused by a high yield in a normal shot time, or a regular yield with an excessively long shot time. Once you get your head round these simple formulas, it becomes easier to understand/fix your shots.



Throughout my experience dialling in countless blends on countless grinders, the most important piece of knowledge I can impart to you is to keep notes. Weigh everything and write it down, this alone will make you a better barista. Write down which steps/recipes work and which don't. Keep a note of what you think is wrong; is it too sour, too thin, too bitter? Do you want more sweetness or fruit, do you feel like you're missing part of the profile that other people have noticed? Keep playing, and look for patterns between these notes and recipes.



Anyone can make great coffee through enough trial and error, but being a good barista is about knowing exactly what to do to get the coffee you want to drink. And above all, have fun with it!



Chris Weaver has been a barista for coming up to five years now, working for some of the most prestigious speciality coffee shops around the UK. He also used to run Common Grind, as Chris puts it: «a podcast and blog inspired by the early Coffee Geek podcasts» in which they primarily focused on live coffee tastings as well as interviews with some of bigger names in coffee coffee such as Jim Hoffmann and Steve Leighton. Currently he is living and working in London as head barista for a coffee bar called Store Street Espresso, serving Square Mile in Bloomsbury. Send Chris an e-mail by clicking here





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