Coffee is one of the most consumed beverages around the world Whether it’s iced or hot, people can’t get enough of this drink. Some can even drink about five cups of joe daily. They drink it not only because they need caffeine to boost them up, but also because of its complex taste, especially specialty-graded ones.
Has it ever crossed your mind how your favorite beverage is produced? If you think coffee farming is just stripping the cherries from the tree branches and getting the beans out of those fruits, brace yourself as you’re about to learn more than just farming. In other words, your favorite drink undergoes the so-called “coffee processing.”
Most people enjoy different coffee-based beverages, such as espresso, mocha, cappuccino, and more. On the other hand, other coffee enthusiasts enjoy drinking black coffee. However, only a few people know the different kinds of coffee, as well as the different processes used by farmers. You’d be surprised to know how these processes provide a huge impact on the notes of a coffee once roasted and brewed.
Post-Harvest Processing
How farmers cultivate coffee trees may provide a big impact on the quality of the harvested coffee cherries. However, the processing doesn’t stop after the harvest. Farmers still need to perform a post-harvesting process to ensure that the harvested beans are high-quality. This process is more than just separating the pulp from the bean.
If the post-harvesting process is not done properly, it can significantly compromise the quality of the harvests. On the brighter side, proper processing can pull out the goodness from these meek beans. Hence, it’s the reason why there are various coffee processing methods introduced in the industry these days.
Importance of Coffee Processing for Quality Coffee
Separating the fruit to obtain the seed is the meekest definition of coffee processing. Surely, you can roast green beans right after separating these, but the taste will undoubtedly not be undesirable. The main reason why farmers invest time in processing is to ensure that the beans are not only high quality but also to develop the flavor. The more complex is better, and it’s possible with proper processing.
Coffee bean harvesting and processing should always come together, especially if you want to play around with the flavor potential of your coffee. Improper processing will still affect the quality and flavor despite growing in well-conditioned soil. Different processing methods bring out the bright and juicy flavors, or they can also emphasize the floral taste. It may sound unbelievable, but it’s the truth. Speaking of coffee processing methods, here are some methods that farmers practice on their coffee farms.
Coffee Processing and its Different Methods
Coffee processing is always a must after harvesting. This process is getting rid of the layers of pulp, skin, parchment, and mucilage, which surround the bean. These layers don’t go to waste as farmers can sell these raw ingredients in the market. As for the obtained beans, these have to undergo processing for better flavors and quality.
There are two main methods on how to process coffee:
Natural Process Method
The natural process is an older technique that farmers used in processing. It’s the process where coffee cherries are put on mats, patios, or raised beds for drying, which is after the flotation. This process is done in places with limited or without consistent access to water, and it’s also mostly done in regions with hot temperatures.
The risk when it comes to the natural process is that the cherries can spoil when they are not repeatedly done for thorough drying, which can make the coffee taste yeasty or sour. On the brighter side, when the fruits are processed well, the coffee can have fruity flavors such as berries, or it can have wine notes.
Washed/Wet Process Method
Washed process, also referred to as the “wet process,” is the most frequently used method for processing. It’s preferred by most farmers as the produced coffees have a higher acidity, which is also known as the “brightness.”
However, with this process, you’ll need more than just raised beds, such as a pulping machine or mechanical dryer, if you don’t want to use the beds.
Aside from the two main methods, there are also other processes introduced these days. Some farmers also consider these processes:
Honey Process
The honey process is a combination of washed and dry processing, which is also known as a “pulped natural process.” With its distinct process, it can achieve a coffee with low acidity and body, which is similar to natural processed coffees. However, it doesn’t taste like vivid fruits, unlike in the natural process.
When it comes to the honey process, the darker the color of the coffee beans, the more mucilage it contains. There are different types of methods that fall under the honey process as well, and here are the most used:
- Yellow Honey – Yellow honey-processed coffees are more balanced since it has lesser mucilage. It has a little acidity with less sweetness and less body.
- Red Honey – Red honey-processed coffees have more mucilage than yellow honey, which results in a sweeter taste, with high acidity and medium body.
- Black Honey – Black honey-processed coffees have all the mucilage, which makes it risky yet complex. It has sweetness, an excellent amount of brightness, and a heavy body.
Wet Hulling
The wet hulling process or also known as “giling basah” is a unique coffee processing method used in Sumatra, Indonesia. It’s known for its low acidity, body, and earthiness. It’s also similar to the pulped natural process or honey process, yet the drying part typically lasts longer. The challenge is that the beans are delicate.
Moisture Content Importance
Moisture is not a common word that drinkers usually hear when it comes to coffee. It’s why few of them know how important moisture content is. It’s crucial to pay attention to the content of harvested beans as it can affect a coffee’s quality after the brewing. Also, it helps as it brings out desirable flavors and balanced brightness.
When it comes to moisture content, you must pay attention to the drying part of the process. Unprocessed beans have 45% to 55% moisture. Now, the ideal moisture content should be 8% to 12% before storing. You also need to consider other instances such as the altitude of the area where the coffee is grown, or the climate as well. Checking the ideal water level is not something that people can determine by looking at these. Hence, you’ll need to invest in a moisture meter to get water levels accurately.
Green Coffee Beans Storing
Storing may sound meek, yet it’s also considered one of the most important things when it comes to processing coffee beans. Since green coffee beans are very porous, they will absorb anything in their surroundings. Hence, if you store these in a place that’s smelly or moldy, expect your coffee beans to have undesirable characteristics.
The storage material is not the sole thing to consider when it comes to storing green beans. Other aspects that producers, roasters, and consumers shouldn’t take for granted are the following:
- Humidity – When the beans are too wet, it can have a moldy fragrance and a flavor. On the other hand, when it’s hot, it can dry the beans out, which causes aromas and flavor losses. Hence, as per the International Coffee Organization (ICO), the humidity level of the storage should be 11 to 12.5%. Also, it can compromise oxygen levels, wherein it can go inside and out of the packaging used as well, like moisture.
- Temperature – Temperature can also affect the moisture levels of the green beans, regardless if it’s too cold or too hot. Room temperature is recommended by Sweet Maria, which is 68 to 77º F or 20 to 25º C. However, Hanuman Jain states that it will also depend on the packaging, and the range is -22º to 194ºF or -30º to 90ºC.
- Light – Direct sunlight is not ideal for coffee beans as it impulsively ages these. The freshness typically lasts for 12 months. However, when these are stored under bright light levels, aromas and flavors will shortly fade.
- Pests – One of the most inevitable things that mess with coffee beans are pests, wherein holes or bites are your indicators. The worst part is when an insect gets inside the packaging, it will eventually die inside after 24 to 48 hours since it’ll need fresh air.
- Eco-Friendly – Typical cotton bags or burlap are eco-friendly packaging. However, plastic hermetic packaging is also advised since you can reuse the bags, which helps more in making the environment greener.
One of the most recommended packaging for coffee beans is Grain Pro. It’s advisable as it can enhance the quality by securing the coffee beans from oxidation, rancidity, mold growth, and insect infestation. It’s also safe as it averts the fungal contaminants’ growth. Furthermore, there’s no need for chemical pesticides.
If you’re getting more curious about how farmers proceed with the production process, here’s a simple guide for you:
Coffee Production Flow
Coffee production is not as easy as harvesting the goods and storing these for supply. When it comes to coffee, everything should be done properly, from harvesting to storing.
1. Harvesting
Harvesting may be the first process, yet there are some significant things you need to consider, such as the way of doing it. The different methods include handpicking, stripping, and machine picking. So, what makes each method special?
- Hand Picking or Selective Harvesting – Most harvested goods are hand-picked by farmers and one reason why is because they get to pick which the ripe coffee cherries are, leaving the unripe ones unharvested. Coffee takes time to grow, which is why some farmers prefer this method as unripe cherries will not go to waste. However, it consumes more time, and it can be expensive, which were the downsides.
- Strip Picking – Another manual way to harvest coffee cherries is by strip picking, and it’s a famous way. Some farmers prefer this method because it’s quick and convenient. On the other hand, some unripe cherries are being included in the harvest, which needed further sorting.
- Machine Picking or Mechanical Stripping – Not all farmers use machine picking for harvesting because a flat land is required to operate the harvesting machine. It’s very effective, but it’s an expensive investment. Moreover, labor costs are reduced because one person can operate it.
The decision on which harvesting method to use will depend on manpower, land, and the budget of the producers.
2. 1st Flotation (remove floating cherries)
Regardless of what harvesting method was used, all coffee cherries need to undergo the first floatation. Part of the process is removing the so-called “floaters,” which are undeveloped and overripe coffee cherries. Ripe cherries are dense. Hence, this process will determine all the “sinkers” or the cherries that can proceed to the next process.
Washed/Wet Process
The natural process goes straight to drying after the first floatation. However, the washed or wet process has further steps before the beans are dried. Here are the succeeding steps:
3. Pulping
After segregating the floaters from the sinkers, the pulp and the beans come next. Depulping is the removal of the skin or the pulp of coffee cherries, and it needs a machine called “depulper.”
The coffee de-pulping machine uses a blade to open the cherries, leaving the beans with a layer of mucilage. Afterward, the empty cherries are set aside for other uses.
4. 2nd Floatation (remove floating beans)
After the pulping process, the beans still need another round of floatation to determine the ripe beans. It’s similar to the initial floatation to determine the overripe or undeveloped cherries because of the ripe ones. The pulpedcherries pass via water channels to segregate these by weight. Some farmers use a sequence of rotating drums to set these apart by size.
5. Fermentation (pH level)
Fermentation is a chemical reaction, wherein bacteria, yeast, and other microbes are combined to break down into meek substances. Moreover, these substances turn into sugars.
This step is also considered one of the most important steps in processing because it’s what makes the coffee more delightful as well. It can enhance the flavor, but, it can also compromise it. If you’re wondering how farmers do it, here are the two methods:
- Anaerobic – In this process, farmers place coffee cherries inside a tank, which is either after or before pulping. Afterward, the tank is filled with water as the cover, which lets various microbes work.
- Aerobic – This process occurs when there’s oxygen. What happens is that the cherries are put inside a container or a tank, and let the bacteria do the work. However, it’ll need a little effort in checking the temperature and time for controlling and analyzing.
The fermentation time ranges from 16 hours to 25 hours. You’ll know that the process is over when there’s a Brix reading of 8°Bx, which means 8 sucrose grams per 100 sample grams. It’s also crucial to control the pH level, wherein it shouldn’t go lower than 4.5. Moreover, it can remove the mucilage left from the bean.
6. Washing
Since coffee beans undergo fermentation, they should be washed properly. In washing these, most farmers do it carefully with clean water inside containers. Some are even using washing machines that are intended for coffee.
7. Drying
The washed or wet process needs the drying phase as well. It sounds easy, yet this step is risky because it can expose the coffee beans to bacteria and physical weakening. On the brighter side, it can help a lot in reaching the desired moisture content.
While natural processed coffee can take up to four weeks, the drying period for washed-processed coffee is 7 to 15 days. Some farmers are drying the coffee beans on huge patios made of cement or asphalt, some are using drying beds, and some utilize mechanical dryers.
8. Dehulling or Coffee Hulling
The dehulling process comes after the drying of the beans. The purpose is to get rid of the exocarp (in the dry/natural process), mesocarp(in the dry/natural process), and endocarp (in the dry/natural, honey, washed process), which is why it should be dry enough before you dehull the dried cherries with the coffee hulling machine.
9. Polishing
This is an optional process wherein the remaining husks are removed.
10. Coffee Sorting & Grading
Sorting is another significant process in coffee production since all farmers wouldn’t want defects to ruin their coffee’s reputation upon grading. It’s important to sort out the green beans before storing these to remove the defects. Aside from the moisture content, the percentage of various defects can affect the beans’ grade.
In the SCAA grading system, if you want your beans to have a Specialty grade, there shouldn’t be over five dull defects out of the 300 grams used for grading. For a Premium grade, it shouldn’t exceed eight full defects. If there are 24 to 86 defects sorted, then the grade of the coffee is below the standard grade. Moreover, it’s an Off-grade coffee if you have over 86 defects.
11. Storage
Once the defective beans are sorted, and the moisture content hits the ideal range where it should be, the green coffee beans are ready for storage. Even though storing is the last step in the process, producers should do it properly, or else, the quality of the green coffee beans is still compromised.
Aside from GrainPro, there’s also other packaging for green coffee beans such as the Sisal bags and vacuum packaging. Sisal bags or hessian sacks are made from vegetable fiber, and it’s the most inexpensive natural fiber used for packaging. As for the vacuum packaging, it’s the cheapest packaging, and it’s the ideal packaging for quality conservation as it keeps the beans from water or other things that can compromise the quality.
With all the processes of coffee production, it’s not as quick and as easy as finishing a cup of coffee in one sitting. From bean to cup, coffee undergoes a lot of processes, and the effort is not only in the hands of farmers. Moreover, it’s undoubtedly a thorough process, yet the end product is worthy. The best thing we can do to support them is by appreciating every cup of coffee as it is.
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