Our approach

I am a small-scale independent coffee roaster based in Tewkesbury, Gloucestershire, just south of the border with Worcestershire. 

Single Dose Coffee is a passion project rooted in an obsessive desire to achieve the best possible flavour from every single coffee bean. I achieve this in six stages, described below.

First, I select the green (unroasted) coffee. I work only with exporters who can guarantee traceability, ensuring fair pricing for farmers whose livelihoods are essential to the future of speciality coffee. I look for exceptional beans that shine on the cupping table, providing an exciting canvas for the development of a roast profile to showcase the unique flavour potential of each bean.

Second, I take a sample of the green coffee and measure the moisture content, density and size of the unroasted beans. Together with other information - about the origin, the varietal, the altitude at which it was grown, and the way in which it was processed - I develop a roast profile, planning the desired temperature and airflow at different stages of the roast in order to emphasise the most appealing flavours in the cup.

Third, I use that profile to roast a sample of the coffee, closely monitoring the conditions in the roasting chamber to gain insight into the various chemical changes underway. Once roasted, I allow the sample coffee to ‘rest’ for a fixed period, during which time it will continue to develop new flavour compounds, whilst releasing carbon dioxide and slightly darkening in colour.

Fourth, once the resting period has passed, I weigh the roasted sample and compare it to the weight before roasting to determine the moisture loss. I then use a colourimeter to take precise readings of the colour of the surface of the beans, before grinding the sample to take another reading of the colour of the inside of the beans. This gives me an insight into how evenly the coffee took on the heat applied during roasting, which helps to inform what changes might need to be made to the roast profile to ensure that the coffee is fully developed.

Fifth, I brew the ground coffee using an industry-standard method known as cupping. This involves mixing a set ratio of grounds with water for a set time, before smelling and tasting the brewed coffee and noting the flavours that emerge as it cools. To ensure standardisation between cups, I use a particle size analyser to confirm that the size and distribution of the ground particles is within set parameters, a temperature-controlled kettle and timer, together with water of a defined mineral content. I also use a refractometer to indicate the solubility of the roasted coffee, which is a good indicator of roast development. Together with colour and flavour, these measurements indicate whether the roasted coffee is properly developed and has optimum extraction potential, or whether small changes to the roast profile might yield better-tasting results. Ideally, I will cup several roast profiles alongside one another, enabling me to determine which variables lead to the best result in the cup. 

Finally, once I have settled on a roast profile for production roasting, I keep track of the parameters measured above to ensure consistency between batches. I deliberately keep the batch size constant between sample roasts and production roasts to minimise the changes that need to be made to the roast profile. This is very labour-intensive, but enables me to be confident that each roast has behaved similarly, so you can have confidence in what you’re buying. To help with this, I use a between-batch protocol on my roaster to ensure thermal consistency in the roasting chamber between roasts. If colour, solubility or flavour start to drift, I’ll tweak the profile to get the coffee back on track.

Soon, we’ll be putting together some YouTube videos about this process to bring it to life. Please be sure to subscribe to our channel be notified when our first video drops! www.youtube.com/@singledosecoffee