Your complete guide to green coffee beans
Despite drinking countless cups of coffee, many of us have never seen coffee in its original raw form. In fact, if we asked you to picture a coffee bean in your mind, chances are the first image you’ll conjure up will be a small, oval-shaped brown bean.
However, a coffee bean’s natural colour is green, not the chocolate brown that we know so well. These raw beans have wildly different flavours, aromas and tastes compared to a brown coffee bean and must be roasted to unlock the complex, beautiful coffee experiences that we enjoy so much.
Here, we explore the world of the green coffee bean, discovering everything from its origins to how it gets its signature coffee colour.
What are green coffee beans?
A green coffee bean is the unroasted seed of cherries grown on coffee plants. These cherries are roughly the size of a grape and made up of two central seeds, surrounded by pulp and protected by the fruit’s skin.
Once harvested, the cherries, which are usually red in colour, are processed and either left to dry in the sun or are washed in water, removing the pulp from the coffee bean. During this process, beans start with a moisture content of around 60% and by the end, are dried to approximately 12%.
When the green bean is separated from the pulp, it is ready to be roasted. It is during the roasting process that the natural green colour of the coffee bean turns to brown. As water is driven out of the bean and it starts to experience a build-up of gases such as carbon dioxide, this brown colour intensifies, with the bean expanding in size and shedding its green papery skin.
How do you roast a green bean?
Roasting coffee is considered by many as an art form, the somewhat magical process which turns comparatively flavourless green beans into beans with incredibly complex flavours and aromas.
With beans ideally roasted as close to consumption as possible, there is a wide variation of roasting methods available. The most popular types of machines used by professional roasters include drum roasters, centrifugal roasters, hot air roasters and tangential roasters.
How can you roast green beans at home?
Most people leave coffee roasting to experienced suppliers and specialists. However, if you’re brave and enthusiastic, you can certainly roast your own green beans. Roasting your own beans guarantees superior freshness and also opens up an immensely enjoyable world of experimental roasting and flavours.
Many London and UK roasters rent out machines used for their micro-lots, so it’s worth contacting a nearby roaster or coffee brand in your area. Alternatively, you can try your hand at DIY home roasting.
All you need to give green bean roasting a go at home is at least one of the below:
- Frying pan
- Stovetop popcorn maker
Once you have your home roasting device to hand, follow the below instructions:
- Preheat your device to 250°C.
- Add your beans (green), stirring gently and continuously. Only add a handful, not the whole bag. The beans will expand in size, so give yourself enough room to stir and move them around the device.
- After around 5 minutes, the unroasted coffee should make a crack or crackling noise and turn yellow in colour. You should also start to smell a grassy sort of aroma.
- You can stop roasting now or carry on to allow beans to caramelise further. This will enable a deepening in colour to the brown we usually associate with our regular coffee beans. Keep a close eye on your beans, ensuring they don’t burn.
- Once you’re happy with your home roast, it’s time to cool them down. Use a colander/sieve to shake off their excess skin.
- Leave your batch to cool and rest on a cooling tray overnight (or for at least 8 hours), allowing the release of excess CO2.
You can also roast your unroasted coffee in an oven; however, as you’re limited in your ability to stir your green, unroasted beans continuously, this method is much harder to control.
Can you drink green unroasted beans?
Raw and unroasted, the pistachio-hued green coffee bean may not be as tasty as roasted beans but is in itself a powerhouse of nutrition with alluring health benefits. Complex in nature, they’re loaded with over 40 substances responsible for taste.
The secret to green coffees’ health benefits lies in a chemical called chlorogenic acid. While regular roasting eliminates much CGA, green coffee beans are abundant in it. CGA works by inhibiting an enzyme called glucose-6-phosphate, which is responsible for storing sugar in your liver.
Some health professionals suggest that a regular intake of green coffee beans can reduce the chance of developing diabetes, speed up the metabolism, and can positively affect blood vessels to reduce high blood pressure. What’s more, green coffee bean drinks are stacked with antioxidants (for example, green coffee has ten times more polyphenol antioxidants than green tea).
To make a perfect cup of green coffee, simply use a grinder to grind up your coffee beans (green/raw) to a coarse consistency. Add a heaped teaspoon to a cup of hot water and let it steep for about ten minutes. Once the powder has dissolved, strain and serve.
Where can I buy green coffee beans (UK)?
If you like your coffee beans green, shop Coffee Direct for premium green coffees from the finest growers across the world. With over 30 years’ experience delivering 100 variations of speciality beans (from Papua New Guinea to Kenya, single-origin coffees to unique blends) direct to your door, we are connoisseurs of variety, flavour and provenance.
Are green coffee beans good for weight loss?
Since chlorogenic acid affects how fast the metabolism burns fat, green coffee beans are said to be a natural weight loss aid. It is claimed that they can raise your basal metabolic rate (BMR), which is responsible for how quickly your body processes nutrients and stores deposits of glucose and fat.
How long do green coffee beans last?
One of the joys of green coffee beans is their longevity. Compared to roasted and ground coffee products that can lose their flavour within a matter of weeks once opened, green coffee beans’ shelf life is up to about six to twelve months after processing. Be sure to store in an airtight container away from light, and your green coffee beans will make a tasty brew for months to come.
How much does green coffee cost?
The price you pay for a green bean coffee product varies depending on numerous factors such as: where the bean is produced (e.g. Costa Rica vs Brazil, Ethiopia vs El Salvador, Colombia vs Guatemala etc.), whether it is single-origin or a blend, and how it is processed (a foraged Kopi Luwak coffee vs machine picked bean from Brazil). Again Coffee Direct's handy website filter for coffee (green bean or regular) can help you find a selection for your budget. Adjust the settings from price low to high (or price high to low), and a list of items will be presented for you to add to your cart and purchase.