Bean Insight: Lifting the lid on coffee creation post-roasting (part two)
If you’ve read the first installment in this special two-part blog, then you’ll have probably realised by now, that there’s a whole lot of work involved in producing great coffee!
In our last blog we talked you through the process of roasting, but that’s just the start. After roasting, there are even more stages involved in producing the perfect cup of coffee. Read on for details of what they are.
No, coffee cupping isn’t the ancient form of alternative medicine, it’s what people within our industry do to evaluate the coffee once it’s been roasted. It’s our way of analysing the tastes and aromas of the brewed coffee.
Not too dissimilar to wine tasting, cupping is a standard practice to assess aromas and flavour characteristics of different coffees. We smell the dry grounds and also the coffee when it’s brewed to get the aromas, and then we slurp the coffee, making sure we coat the entire tongue. We’re looking to measure the body, acidity, sweetness, aftertaste and general flavor and we often compare and contrast this with other coffees on the table. It’s also worth noting that we keep tasting the coffees as they cool because the drop in temperature will sometimes reveal flavours that were previously hidden.
Coffee grounds contain a whole bunch of components, such as oils and acids that are more commonly referred to as ‘coffee solubles’ and every cup of black coffee is a mixture of water and these coffee solubles in varying amounts. In order to get the perfect cup we need to extract the right percentage of solubles and then dilute this with the right amount of water.
Without getting too technical on you (we did tell you coffee is a science!), solubility is measured by: (1) Total Dissolved Solids and (2) Extraction yield and we measure these with a device called a refractometer.
Total Dissolved Solids (TDS)
The TDS is the percentage of soluble coffee solids in a cup. In a nutshell, it’s the strength of the concentration of the coffee/water mixture. The higher the percentage, the higher the coffee to water ratio and the stronger it will be. Typical figures are about 1.2-1.5% for filter coffee and 8-12% for espresso.
This is the percentage of soluble coffee solids extracted from the ground coffee once it has been brewed. Generally, coffee with an extraction yield of anywhere between 18-22% will be full of flavour, sweet and well balanced. Coffees that are under 18% can often be grassy and peanutty, and over 22% will risk being bitter and astringent.
Last, but not least, once the tinkering, testing and refining has been carried out, there’s the best bit to look forward to – the ultimate taste test! After all that hard work, there’s nothing more rewarding than pouring yourself a flavoursome cup of coffee that ticks all of the right boxes!
Got any questions or want to find out more about the art and science of creating coffee? Or perhaps you’d like to discuss your coffee requirements with us? Call us on 0845 257 5900.