Before they find their way to your kitchen, the coffee beans that make up your favourite brew have been lovingly grown, processed and sent across the globe for you to enjoy. In fact, every step of the production process affects the coffee’s final quality and flavour.
In particular, the processing method used to separate the bean from the fruit can greatly affect the final product that you enjoy, whether it’s in the form of an espresso, cold brew, or a frothy latte. So, what are the steps of coffee processing? Let’s take a closer look.
Coffee passes through several different stages in its production cycle. These can be broken down into five key steps, as follows:
the beans can then be roasted, splitting them open and changing their colour from green to brown. The temperature and duration of a roast will greatly influence the final flavour of the coffee.
the beans can then be roasted, splitting them open and changing their colour from green to brown. The temperature and duration of a roast will greatly influence the final flavour of the coffee.
the beans can then be roasted, splitting them open and changing their colour from green to brown. The temperature and duration of a roast will greatly influence the final flavour of the coffee.
the beans can then be roasted, splitting them open and changing their colour from green to brown. The temperature and duration of a roast will greatly influence the final flavour of the coffee.
the beans can then be roasted, splitting them open and changing their colour from green to brown. The temperature and duration of a roast will greatly influence the final flavour of the coffee.
Coffee processing refers to the method of removing the seeds (or as we know them, the beans) from a harvested coffee cherry. As with many pitted fruits, the seeds of the cherry are stored in its centre, and need to be extracted and dried before they’re used.
The beans are surrounded by several layers. The first is a coating of dry “parchment” tissue that encases the beans, followed by a sticky substance named mucilage, then the pulp of the fruit, and lastly, its outer skin.
Once harvested, coffee cherries are moved into floatation tanks to check for ripeness. The unripe fruit tends to float to the top and is then removed from the batch. Next, there are four main ways of processing coffee, each of which affects the sweetness, aroma, acidity and body of the final brew.
Natural processing involves leaving cherries laid out on drying beds with each of the layers of fruit around the beans still intact. Over several weeks, the beans are exposed to the sugars and mucilage of the fruit, and gradually ferment. Once dried, the beans are mechanically hulled to remove the other layers. This produces coffees that are heavy-bodied, syrupy and sweet — with bright notes of fruit and chocolate. However, beans within a batch may be inconsistent in quality and flavour as a result of the uncontrolled fermentation process.
During washed processing, pulping machines mechanically remove the beans from coffee cherries, and they are passed into tanks of water to be washed. The beans typically soak for 12-24 hours to remove any leftover mucilage attached to the beans. Once clean, they are laid out to dry for several weeks and then hulled. This process is undoubtedly fast, but energy and water-intensive. Washed processed coffees carry clean, crisp and floral notes, and are lighter in body than naturally processed coffees.
You’d be forgiven for thinking that actual honey is involved in this kind of processing — but it isn’t. Instead, coffee cherries are passed through a pulper and the beans are left to dry with varying amounts of mucilage (the “honey”) still attached. This unusual method skips the mucilage-soaking step used in washed processing, leaving a little fruit to ferment the seeds as they dry. The beans are then hulled. Honey-processed coffees are varied and complex in flavour, with rich sweet notes of plum and almond, a little acidity and a smooth body.
Also known as “semi-washed” coffee, wet-hulled beans are removed from their cherries using pulping machines, then moved to plastic tanks with their moist mucilage still intact. This creates a thick layer around the beans, which is then removed in hulling, and they are laid out to dry. Wet hulling is a quick and efficient process thanks to the reduced drying time, which is ideal for humid climates. Wet-hulled coffees typically boast nutty, earthy notes and low acidity.
After coffee is processed, the green unroasted beans are distributed to roasters. During the roasting stage, beans are heated and transformed into the fragrant, dark coffee beans that we grind up for our brews. Each roaster will follow its own unique regimen for roasting coffee beans, applying different temperatures and cooking times to produce the desired flavour profile.
So, now that you’re up to speed on the different methods that are used to process coffee, look out for the processing method detailed in the information shared with you when you receive your next batch — and remember the complex production chain behind your favourite brew!
