Coffee Roasting Best Practices (Part 1 of 5)
- Coffee Roasting Best Practices (5 Part Series)
- Part 1: Choosing Quality Green Coffee Beans
- Part 2: How To Store Green Coffee Beans
- Part 3: Preparing for Roasting
- Part 4: Roasting Process
- Part 5: Cooling & Storage
Ever wondered just how coffee roasters and baristas at your favorite coffee shop curate the perfect coffee flavors? It all begins with the first step of choosing quality green coffee beans. After all, green coffee beans aren’t created equal.
Choosing just about any bean can be the recipe for a journey to a disastrous coffee brewing experience. After careful research on the ground, we’ve compiled an invaluable guide on choosing the perfect quality green coffee beans – should you ever decide to do the sourcing yourself!
Importance of Selecting High-Quality Green Coffee Beans
Coffee only works like most food items. You can put little effort into the selection of many other foods. A fresh, organic batch is enough to help you craft a delicious and fresh meal. Selecting the highest quality green coffee beans directly impacts the flavors of coffee brewed from these beans. Green coffee beans allow you to experiment with the roasting flavor. A poor choice will not give you this opportunity.
Factors to Consider When Choosing Green Coffee Beans
The undertaking can be confusing and intimidating if you start sourcing your green coffee beans. The good news is that there are principles and steps to follow and guide you through the process. Here are essential factors to look out for when choosing the best green coffee beans;
Track the Origin
The origin of green coffee beans tells you a lot about the growing conditions. These include the climate, soil type, humidity, altitude, and even locations (for instance, is it near a volcanic area?). All these factors play a role in determining the overall flavor. For example, Arabica coffee beans are grown in the foothills of the volcanic Mount Kilimanjaro, impart fruitier, floral, and chocolatey tasting notes.
On the other hand, the shallower hilly, non-volcanic land in the NorthWest Tanzania region of Kagera harvests more subtle earthier, flavored robusta coffee. You can always pinpoint the flavors you want to achieve by sampling coffee from .
If you want to focus on a particular taste profile, go the extra mile to find your coffee’s origin farm. In this case, direct trade and relationships with specific farms help. This is because, in many cases, coffee is labeled as single origin, and the single farm isn't that in reality. Many sellers would pack single source from different farms, impacting the flavor in return.
Focus on the Altitude
The altitude where your coffee grows is significant and worth creating its section. Higher altitudes equate to lower temperatures. This, in turn, slows the growth of the beans, allowing sugar to develop more. As a result, coffee grown at higher altitudes produces more complex and sweeter flavors with depth and acidity.
Understand the Processing
Processing green coffee beans involves taking the seed from the coffee cherry. Now, this part also impacts the final flavors of the coffee. It’s a good idea to familiarize yourself with the different processing types and how they affect the taste. The most popular methods are natural/dry and washed/wet processing.
The natural or dry processing involves sun drying the freshly picked cherry with the seed inside on outdoor raised beds or sacks covering the ground. The natural method allows the cherries to develop a heavy-bodied profile with sweet and smooth flavors.
While it’s considered a more limited method in places with poor water supply, it is favored. This is because it helps the cherries harness more flavor varieties. You also get a significant flavor depth from naturally dried coffee.
On the other hand, the washed or wet process involves seed removal before sun-drying. With the seed removed, the cherries develop a cleaner taste with bright fruity notes and more acidity.
Examine the Appearance
Good quality green coffee beans should be uniform, with a minimal number to no beans with deformities. You will notice this consistency if you buy packaged beans from a supplier. Direct trade with farmers will give you more inconsistencies since they don’t hand-pick the sizes. However, this doesn't mean the coffee will be poor quality.
Instead, you should focus on consistency in size and color, as this indicates that the beans are treated the same way from growth to harvest and processing. This also means that during roasting, the beans' size and color make it easier to ensure even roasting.
When examining green coffee beans, look for moisture content and water activity. While more prominent coffee buyers use special equipment, visual inspection is acceptable for small batches. Even while still containing moisture, the beans should look dry with no mold build-up. This ensures proper processing, transportation, and storage.
In reality, unprocessed coffee beans contain about 45 to 55% moisture post-harvest. After correct processing, the cherry typically loses about 10 to 12% of its moisture. Anything lower than this will mean the beans have been under-dried, which impacts roasting and flavor.
Always Buy Ethical Coffee
Coffee farming is demanding and features a long supply chain. Therefore, it’s straightforward for the farmer to be cheated out of the profits they deserve. In many low-income countries, farmers struggle with low wages and a lack of safety equipment. So, investing in ethical coffee is essential to protect the farmers' rights.
If you plan on trading directly with the farmers, buy from reputed importers that source fair-trade coffee. Such sellers usually share fine details of green coffee's traceability. Another easy way to identify ethical coffee is by looking at the price.
Remember, coffee goes through a long supply chain. You have to think of the farmer that harvested (their farm hand, equipment, and time invested), processing, transportation, storage, and packaging till it gets to your hands. In this case, significantly cheap green coffee beans are probably not ethically sourced!
Do Quality Sampling If Necessary
If you are putting together house blends for your coffee shop, go the extra mile by investing in essential quality control equipment. You first want to get small samples (at least 8 ounces) of the different coffee you wish to use and sample the flavors. The simplest way is by roasting and brewing the coffee to taste it. But, to get more qualitative and objective results, you can implement a standard quality control system. Some of the standards you can implement include the following;
- Maintaining a unique tracker (as simple as a Google sheet on your company laptop) for every batch you receive (recording information like defects, notes, and overall flavors). Over time, you can evaluate each coffee after receiving several lots. You can then decide which type experiences more defects and has the best flavors.
- Use a small sample for each coffee bean lot for sample roasting to ensure you get the expected flavors. You can even use these samples as the control. For instance, if you notice too many defects in the small sample sizes, you are better off ditching that blend as it may need better quality.
- Get a moisture and density analyzer, water reader, and UV flashlight to examine each coffee’s moisture content. Note: you may need an expert to train you and your staff.
Don’t forget to test in a controlled environment with the proper humidity, pressure, and airflow. Ideally, mirror a roastery or storage facility. As a general rule of thumb, examine the large consignments of beans meant for coffee shops in the following manners:
- Visual grading of the green coffee beans by their appearance
- Track water activity and moisture content
- Track your data (coffee’s origin and examinations)
How to Source Quality Green Coffee Beans
You can source quality green coffee beans via three primary sources.
The most convenient option is online retailers. You can find a variety of vendors online with beans from across the world. However, you have to exercise extra caution as it is easy to get duped by these retailers. Ideally, go for a reputed seller – research genuine customer reviews to understand better if it’s your first time—online sellers, like coffee shops, cater to small and more significant buyers.
Importers sell coffee in larger consignments for customers, such as coffee shops or roasteries. Importers have already harnessed networks and have the financial capacity to source coffee from various regions of the world. This makes stocking up on green beans from multiple areas easier without spending a fortune.
Direct trade is best if you want to create more meaningful relationships and enjoy better traceability and transparency. This option even gives a better opportunity to examine the coffee and ensure you get a fresh batch by being looped in on the processing and transportation part. However, you have to do the leg work and visit the farms in the coffee-growing regions of your choice.