Signature drinks remain a little controversial within barista competitions. Some believe that they are a great outlet for creativity, whilst others argue that they have nothing to do with pushing great coffee forward and are an unnecessary part of the routine on stage. Personally, I love them, and take great pleasure in the challenge they bring. They are one of the things I will miss the most when I stop competing next year.
A good signature drink has to score well on taste, but I think it is important to think of the audience as well. Not only is it difficult for the audience to judge differences in performance while watching a barista prepare espressos and cappuccinos, they don't even have the opportunity to taste the drinks. For them, the signature drink may be the most interesting part of the 15 minutes a barista has on stage.
Developing the signature drink
Many people approach competitions and signature drinks from the point of view of the café, and what is practical within the confines of serving coffee in the normal course of business. For that reason, signature drinks are often created with the intention of being something that could be served at a busy bar. These drinks tend not to score as highly, as people make them too large; judges tend to want a strong taste of coffee, which means that the drink has to be pretty small - go much past 5 oz, and you are starting to push it.
Competitors who really enjoy signature drinks nearly always have one eye open for glasses or cups to serve a drink in. Sometimes a glass might inspire an idea, and some drinks just wouldn’t be possible without a very specific vessel to serve it in. Jon Lewis’s blood-orange-based drink served at the USBC in 2006 seems only possible if served in the rather wonderful port sippers that he used. I am sure I am not alone in having an odd collection of glassware waiting one day, perhaps, to be used on stage.
My signature drinks tend to start off as abstract concepts, usually in terms of their construction rather than a specific flavour pairing - though other people tend to work very differently. Previous drinks I have created were developed in this way - for example, last year I created a drink with two liquids layered vertically instead of horizontally. The idea of how it would look and be constructed came before I considered the flavours that would go into it.
Unfortunately, the constant striving for originality in signature drinks often leads us away from ingredients that work really well with coffee. If you break down the scoresheets, there are only six points allotted for creativity, inspiring us to crowbar unusual flavours into the drinks. These unusual ingredients may create an impressive sounding drink, but there are four times as many points available for how good it tastes. My personal opinion is that you can use all the “classic” ingredients that are usually paired with coffee as long as you find a way to present them in a way that is interesting and, most importantly, tastes really good.
For my first competition, I created a signature drink that had chocolate, cream, almonds, milk, and hazelnuts in it. The drink scored well on creativity because I made a ganache from the chocolate, cream, and butter after I had infused the cream with some incredibly aromatic and great pipe tobacco. The other ingredients were used to create a foam that tasted like biscotti that sat on top of the coffee / chocolate / tobacco mixture. It remains the drink I am most proud of.
There seems to be more and more experimentation and incorporation of new cooking techniques into signature drinks. Billy Wilson came up with a brilliant way to serve the espresso caviar he created using alginate in the NWRBC 2007 - an event he won. It was interesting to see that David Makin, Australian Barista Champion 2006, used liquid nitrogen as part of his routine to win his regional this year.
For the UK Barista Championships in 2007, I wanted to create a drink that was a classic flavour pairing, but still do something innovative. My initial idea had been to use a pastry, and the idea of creating a liquid pain au chocolat appealed immediately. The challenge was to create a pastry liquid or foam that I could layer onto an espresso with a little liquid chocolate in the base. The liquid pastry didn't work. I knew I had to really bake the pastry longer than you would want to - to try and stop the starch turning the liquid gloopy, as well as creating more maillard flavours from the browning process.
Whatever I did, the pastry liquid had an odd sourness, especially pronounced if the pastry was infused into milk instead of water. So having gone back to the drawing board I decided, with a little amusement, to try creating some sort of liquid donut.
This presented new challenges for me, mostly due to the amount of fat present in the donut and its effects on the foam I wanted to create with it. I had tried infusing into water and adding a little whey powder so it would foam, but that just didn't work, especially when mixed with the coffee. In the end, the only solution that came to mind was to use a centrifuge to separate out the fat. I bought a small centrifuge on Ebay a year or two ago; I had always wondered what sufficient spinning would do to espresso but never found the correct tubes to fit my antiquated model. For the quantities of liquid I wanted to spin, the machinery had to be a lot bigger than anything I had on hand.
I spent some time at the labs of the Fat Duck restaurant using their centrifuge - they have a Hettich Rotina 35, capable of 10,000 rpm with a max of load of about 200 ml. The first few experiments went very well - the spinning forced any solids to the bottom, whilst the lighter fat floated to the top. The remaining donut milk retained a lot of taste and foamed almost as well as normal milk. However, 200 ml wasn't really enough to use in competition, so I had to compromise speed for volume. For the competition, I used a Beckman centrifuge spinning at around 4,500 rpm that allowed me to spin nearly 700 ml of liquid, which was plenty. I decided to use a refrigerated machine, because I could keep the chamber at around -10 C; then the fat would not only float to the top, but also solidify, making straining it off a little easier.
The Liquid Donut:
Coffee and a donut... yum!
For every 100 ml of milk, use one fresh donut (I generally worked in 600 ml batches). Cut up the donuts and squash them flat. Pour over cold, whole milk, and stir and mix the donut in as much as possible. Allow to come up to room temperature, and leave for about 30 minutes.
Strain as much solid from the mixture through a sieve as possible. Squeezing as much liquid out of the donut pieces as possible ensures you get some of the tastiest liquid!
Sweeten to taste using white granulated sugar - 1 tsp per 80 ml should be plenty.
If you are using a centrifuge and spinning large quantities of milk, be aware that it is vital that the tubes should all weigh the same, to within 1 g of each other. For my signature drink, I spun two tubes of 120 ml each. After about 4 minutes at 4,500 rpm (or a relative centrifugal force of about 3,800 g, if you are using different rotors), all the solids should be stuck to the bottom of the tube, and some fat should have solidified at the top. If your centrifuge is not chilled, then the fat may be seen as an oily layer on top.
Strain to retain the donut milk only. Steam as you would steam milk. You may need to refine the texture of the foam a little, as it is quite hard to stretch the liquid at first. I tend to use an aero-latte (the tool of the pro barista!). Add in equal quantities to your espresso, grate a little chocolate over the top for decoration, and serve.