Coffee News: from Seed to Cup

What Is Coffee? A Basic Explanation From Seed to Cup

,

We consume over 2.25 billion cups of coffee all around the globe, every single day. An estimated two-thirds of U.S. Americans drink a cup of coffee every day, and those that do total up 18.5 gallons of the brew a year – but that’s nothing compared to Finland, where people drank on average three times as much.

Spanish Version: El Café: Una Explicación Básica de la Semilla a la Taza 

Put it this way, our coffee is very important to us, wherever we are in the world. Yet do we know what we’re drinking and where it came from? To help coffee lovers understand how their delicious daily pick-me-up makes it into their cup, here is the story of coffee — from seed to purchase.

latte art

The latte: More than a drink

Growing Coffee

Coffee takes a lot longer than ten minutes to make. An unroasted green coffee bean is actually the seed of a coffee plant (genus Coffea). There are several species of Coffea plants, with the most common being the Coffea arabica, responsible for 75-80% of global coffee production, while Coffea canephora, aka robusta is responsible for approximately 20% of global production.

It takes approximately 2.5 months for a fresh seed to germinate into a plant, while older seeds can take up to 6 months to germinate. Young coffee plants can be quite fragile and so are usually kept under shade cloth to protect them from the elements.

It then takes about 3-4 years for a coffee plant to begin producing fruit that can be harvested for quality coffee. The plants produce flowers that develop into coffee cherries over a period of between 30-35 weeks.

coffee farm

Growing coffee: It’s not an instant business. Credit: CIAT, Flickr

Harvest and Processing Coffee Cherries

Generally 4-5 years after being planted, coffee cherries are ready to harvest. Most coffee-producing countries have an annual harvest, although some countries like Colombia have two flowerings each year, resulting in two harvests.

Harvesting coffee remains very labor intensive in many countries and is often done by hand. This is often the case because the trees are grown in developing countries where labor costs are cheap or the terrain is too difficult for machinery to operate on.

So how does harvesting happen? The farmer will know the coffee cherries are ready to be harvested when they turn bright red. They are then either stripped from the branch or selectively picked. If they are stripped the picker simply pulls their hand along the branch, pulling all the beans to the ground, regardless of color. Green cherries can be included in the harvest but will negatively impact the taste of the coffee if processed with the ripe ones.  

If the cherries are being selectively picked, the pickers will generally return to the tree again several days later to harvest any additional cherries that have since ripened.

coffee-cherry cross section

Coffee cherry cross section. Credit: Wikipedia

Processing the Beans

Just because the cherries have been picked doesn’t mean the farmer’s work is done: they now need to be processed, so as to get that coffee bean out of the fruit.

The coffee cherry is a coffee bean surrounded by a silver skin, a parchment layer, a pectin layer, a pulp layer, and the outer skin, meaning that these outer layers must be removed. It has to be done quickly after the harvest in order to avoid spoilage.

Coffee cherries can be processed in multiple ways, but two of the most common include:

  • Dry Processing
    This is the oldest method for coffee cherry processing, and the fruit retains the outer pulp before being milled. The cherries are sorted and cleaned, with unripe, damaged and over-ripe cherries removed. It is usually done by hand.

The cherries are then placed on a concrete or brick surface to dry in the sun, and regularly manually turned by hand to ensure even drying. The process is complete after 4 weeks. This method is often used in sunny climates including Ethiopia and Brazil.

  • Wet Processing
    This method removes the fruit covering the seed before drying begins. This requires substantial amounts of water and specific types of machinery. When the cherries are submerged in water, some of the unripe and damaged fruit will float so it’s easy to detect.  

The skin of the cherry, and some pulp, is removed by pushing the submerged cherries through a depulper. The fruit is then either fermented with microbes to break down the pulp or the fruit is mechanically scrubbed to scrape off the pulp.  

If fermentation is used, it must be carefully monitored so that the coffee bean does not take on any undesirable flavors. The wet-processed cherry is left with the silver skin and the parchment layer still surrounding the bean, which is generally dried to circa 10-12% moisture after the wet process is performed.

While these are the two most common processing methods, they’re not the only ones. Find out about honey processing here and wet hull processing here.

SEE ALSO: Everything You Need to Know About Single Origin Coffees

Milling the Beans

The farmer’s removed some parts of the cherry, but not all. So next the coffee beans are placed in a hulling machine; this removes the parchment layer from the wet-processed coffee or the entire dried husk from dry-processed coffee.

At this point, the beans will still have their silver skin on them and they may be polished to remove that skin. This step is optional but polished beans are typically considered superior to unpolished.

The coffee beans are then graded and sorted. Beans that are small in size or blemished might be rejected during this process. Millers also remove beans that are insect-damaged or over-fermented.

Exporting the Beans

At this stage, we have green coffee beans ready to be exported or sold within the domestic market. The size of the global coffee export market is staggering – there is an estimated 5 million people employed in the coffee growing and processing industries worldwide.

Yet just because it’s ready for export doesn’t mean that it’s ready to drink just yet…

Coffee-bag-ready-for-export

Ready for export. Credit: Wikipedia

Tasting and Grading the Coffee

The green beans are often roasted in small batches and sampled by tasters to ascertain the quality of the bean. Beans are also rated on the quality of their appearance, aroma, and color. Tasters may decide to blend batches and even different varieties to obtain certain qualities, although others will remain single origins.

Roasting the Coffee

Now the green beans are roasted in mass and at high temperatures. Yet there are a wide variety of temperatures and durations beans might be roasted at, all of which enhance specific qualities in the bean.  

Coffee roastmasters develop different roast profiles for coffee beans from different sources. The bean’s region, variety, processing method, and desired flavor characteristics will all play a part in determining how a bean should be roasted.  

Some of the most common roast profiles you’ll come across are:

  • Cinnamon Roast 
    Underdeveloped sweetness, grassy, and acidic
  • Light Roast
    Light brown, retains original characteristics of bean and complex acidity
  • American Roast  
    Medium light brown, character of the bean is still preserved
  • City Roast
    Medium brown
  • Full City Roast 
    Medium dark brown, roast flavor prominent
  • Vienna Roast 
    Moderate dark brown, surface oil, bittersweet flavor, low acidity, original characteristics of bean muted
  • French Roast
    Dark brown, shiny, burnt undertones, original flavor of bean hard to taste
  • Italian Roast 
    Nearly black, very shiny, no/low acidity, thin body

Please note: these are merely parameters.

Everyone has different roasting preferences but in the specialty world, the lighter the roast the better.

5483659269_a2ff098ce9_b

Coffee roasting. Credit: Kris Krüg, Flickr

Grinding and Brewing

And you’re nearly ready to drink your coffee! The roasted coffee is next ground to a coarseness appropriate for the brewing method that will be used. For example, an espresso machine will require a finer coffee grind than a French press.

There are many ways to brew coffee including:

Each way of brewing coffee can greatly impact on the flavor of your cup. Part of the fun of coffee is experimenting with different roasts, grinding techniques, and brewing methods to discover the true variety of coffee.

fine-ground-coffee

Almost ready to drink… almost! Credit: Pexels

There’s a long journey from seed to cup, yet every step of the way adds value to your coffee. It’s astounding to think how much work has been done to bring it to you – and how many different coffees, processing methods, grinds, and brewing methods you can try. So next time you’re in a coffee shop, try asking about the different coffees on offer.

Written by A. Weiss  of Doppio Coffee and edited by T. Newton.

Feature Photo Credit:@fincaelreposo

Perfect Daily Grind.

Want to read more articles like this? Sign up to our newsletter! 

Print Friendly, PDF & Email