A Beginner's Guide To Roasting Coffee at Home

If you’re unfamiliar with home roasting you are probably asking why you would want to roast coffee at home when there is much on offer from speciality roasters. Whilst this is definitely true, home roasting can open a whole new range of opportunities for any coffee enthusiast, and has been rising in popularity in the last few years.

With home roasting you can experiment with different roast profiles, understand the differences between different single-origins, create your own blends, as well as learning about the whole process of how coffee is transformed from green beans to delicious roasted coffee.

You may be thinking at this point that this sounds great, but where do I start? Do I need expensive equipment to get started? Whilst home roasters can cost upwards of £1000, you can experiment with something as simple as oven or skillet roasting. These won’t necessarily give perfect roasts, and learning the technique will take time, but it does offer coffee enthusiasts an easy and affordable gateway into the world of coffee roasting. Of course, this will be an experimental process, and you can expect to burn a few batches along the way, but this shouldn’t put you off the learning curve should be fun and enjoyable.

What do I need?

You’ll need three things to start roasting at home. Fresh green beans, some roasting equipment (more on this later), and a bit of knowhow (more on this later too). Other than this, through a bit of experience and time you will open up a world of opportunity for exploring new coffees, creating blends, and the satisfaction of brewing your own home-roasted coffee.

Is it safe to roast coffee at home?

Roasting coffee at home is safe providing the right precautions are taken. Firstly, home roasting must be done in a well-ventilated environment, ideally with a good overhead extractor and a window open. Secondly, attend to the beans for the whole roasting process. Just like when you are cooking, keep an eye on the beans the whole time, and remove from heat if they start burning.

Pan Roasting

You can roast coffee in something as simple as a frying pan or skillet. Start with a medium high heat, and cover with one layer of green beans. Make sure to agitate the beans by stirring them. Soon you’ll begin to notice a colour change. This is known as the drying phase.

After around 5-7 minutes the beans should have changed to a brownish colour, and the beans should start popping. This stage is known as ‘first-crack’. This is around the time you should remove the beans from the heat if you like your coffee medium roast. If you want to go a bit darker, heat for a bit longer. It is worth noting that the beans will continue to develop a little after you remove them from the heat, so it is best to remove from the pan just before your desired roast level is achieved.

After roasting you’ll want to cool the beans. With a home set up this is best done by shaking the beans outside in a colander. This will also help to remove any excess chaff.

Once cooled allow beans to rest for at least 24 hours before brewing and grinding. This will allow the beans to ‘degas’.

Oven roasting

You can also try roasting beans in an oven. Preheat oven to 250C. Distribute coffee evenly over an oven tray. The whole process should take around 12 minutes, but you’ll want to remove the tray and shake the beans half way through to ensure a more even roast. 

Watch the beans through the window of your oven, and also listen out for the ‘first crack’. Like with pan roasting you’ll want to remove the beans after they have cracked (if some aren’t developing as fast these can be removed later).  Just before desired colour is achieved, remove from the oven and cool outside in a colander.

Once cooled allow to degas for 24 hours before grinding.

Home Roasters

There is a whole variety of home roasters out there, so we thought we would just provide a quick overview of the different types available.

Air Roasters- These roasters heat the beans directly through convection by directing hot air over the beans.

Drum Roasters- Essentially a scaled down version of what we use here at our roastery. Drum roasters heat through conduction where a heat source (such as gas flame) heats a rotating drum containing the coffee beans.

Prices for home roasters vary anything from a couple of hundred pounds to upwards of £1000. Generally speaking, the more you pay, the more you will get. Top end home roasters even have chaff collection, air filtration, and a cooling tray.

Summary

Home roasting, particularly without a roaster, offers the opportunity for coffee enthusiasts to gain a whole new experience about what it takes to roast coffee. It may take a while to learn, but can offer the chance to create unique blends, discover a favourite coffee in a new roast profile, and the satisfaction of sitting down and enjoying a freshly-brewed, freshly-roasted cup of coffee.

We sell most of our single-origin coffees here, available in bags from as small as 250g. If you’re creating a new blend bear in mind that different coffees roast differently, so it could be worth roasting separately.