For my espresso recipe, I want to explore how we can go about achieving the tastiest espresso with a high brew ratio. When I first started competing, I had a minimal understanding of espresso recipes.
For my first national competition, I used a ratio of 1,6 with 18,5g in the basket and 30g yield in 30 seconds. It was a very compact espresso because that´s how I thought it was supposed to taste. It was only later that I learned that each coffee has its specific sweet spot and that a barista can alter the flavour expression of espresso simply by adjusting the yield.
From my first, syrupy espresso recipe, I´ve moved in the direction of higher and higher yield. For my 2019 nationals, I used a recipe of 20g in the basket and 46g yield, for a brew ratio of 2,3. This gave a sweeter, more complex and tastier espresso, with notes of apricot, green apple, cherries, and rhubarb.
For my next iteration, I want to go even further. I´ve had some delicious espresso with a brew ratio of close to 3. At such a large difference between dose and yield, there is a significant risk of creating a thin and watery espresso, and most specialty coffees I´ve tried at high yields have tasted just that. However, with a suitably developed coffee containing lots of sweetness and flavour compounds, a high brew ratio can allow you to taste the entire range of flavours without losing body or mouthfeel.
The secret is that the coffee needs to spend a sufficient amount of time in the Maillard stage to create a higher molecular weight. During the Maillard process, amino acids react with reducing sugars in the coffee, breaking down and creating new compounds along the way. If this process goes on long enough, it increases the complexity and body in the coffee.
In other words, high yield doesn´t work for every coffee, because a quick roast will not have sufficient molecular weight to give the espresso body, and a long or dark roast might produce more bitter compounds that will unbalance the espresso. This is why the relationship between roaster and barista is so essential. To maximize the potential of a coffee the barista needs to communicate to the roaster what they want to achieve, and the roaster needs to advise the barista on how the coffee is behaving post-roast, and where they think the sweet spot is.
It´s through this relationship that it´s possible to produce the tastiest high brew ratio espresso.