Coffee cupping at origin is quite different from cupping in the end market. Determining the correct market value is the most important task at origin, which includes "predicting" how the flavor profile will change while the green coffee is in transit to its destination.
We sometimes hear our clients don’t want to buy exotic coffee with floral notes because they had a bad experience with them. When they cupped the coffee at origin, it was floral and fruity with a good balance of sweetness and nutty flavors. However, when they received the coffee in their country 2-3 months later, they felt that the magic had gone away, feeling like they got tricked or overpaid for the coffee. To be safe, they only want to buy coffee with basic notes (e.g., nutty, chocolatey, or caramelized flavor), which rarely presents transit-related flavor degradation.
To be fair, exotic floral and fruity notes generally degrade faster than caramelized or nutty ones, making timing a critical factor when sourcing delicate coffees. After several months in transit, a 90-point coffee might drop a few points upon arrival. In this article, let’s talk about what changes the flavor and how to decide between exotic micro-lots and stable, core coffees.
The Chemical Mechanisms Behind Flavor Loss
There are two main mechanisms that explain why green coffee usually arrives at its destination with a flatter profile:
- Volatility of Aroma Compounds: Coffee aroma compounds are volatile and prone to reacting with other organic components. Naturally, coffee flavor degrades over time because these volatile compounds tend to escape from the beans or transform into other, more stable chemicals. This is why coffee is best consumed fresh. Transportation often introduces higher temperatures that speed up this degradation process.
- Fat Oxidation: Coffee contains about 15% oil. This oil oxidizes naturally and produces a set of aroma compounds that taste papery, grassy, or stale like old crops. These flavors are much more dominant in human perception than lighter floral notes. As a result, the coffee starts to taste stale and plain even with small amounts of oxidation, and high quantities will cause it to be evaluated as defective. Heat during transit also accelerates this oxidation process.
It is expected that the flavor profile changes constantly; there are good practices to slow down the process, but none that stop it entirely. But if all coffee degrades, why didn't my client notice a difference when receiving coffee with basic flavors?
Understanding the Difference
- Exotic coffee: Noticeable change after transportation
- Basic coffee: No perceived changes after transportation
First, exotic coffee contains more volatile aroma compounds than basic coffee. This means exotic coffee has more volatile compounds to lose, whereas basic coffee doesn't have much to lose—hence, buyers easily taste the difference in exotic coffee, but not in basic coffee.
Second, the aroma compounds created by the fat oxidation pathway mask exotic flavors, but don’t affect nutty or chocolatey notes as much. Because those delicate flavors get masked, the magic of the exotic coffee seems lost.
Third, caramel, chocolate, or nut flavors are mostly developed during roasting. Since green coffee transit doesn't alter roasting chemistry, as long as the coffee is freshly roasted, these notes usually remain consistent.
Practical Sourcing Strategies to Protect Delicate Coffees
Now that we understand why exotic coffee undergoes flavor changes during transit, what can we ask exporters to do to slow down the degradation?
1. Air Freight High-Scoring Lots
If you are buying a 90+ micro-lot, using air freight is the most effective option. It shrinks transit time from two months to one week. The retail price of these high-scoring beans is usually high enough to maintain a reasonable profit margin, even after paying higher air freight costs.
2. Low-Temperature Drying
Check with the farmer or exporter about how they dry the green beans. If temperatures exceed 40°C during drying, the cell walls of the beans can be damaged, causing lipids inside the beans to leak and oxidize prematurely. Controlled, slow, shaded drying is strongly recommended.
3. Lock in Water Activity and Moisture Specifications
Require the green coffee to be dried to a homogeneous moisture content of 10% to 12% and a water activity level strictly in the 0.65 to 0.68 range.
4. Delay Dry Milling Until Before Shipping
Hulling too early leaves the naked bean exposed to ambient oxygen and humidity, speeding up aging and lipid oxidation. Keep beans stored in parchment until right before container loading.
5. Upgrade Shipping Protection
Use hermetic packaging like GrainPro, and ask the freight company to install thermal insulation liners (or moisture-absorbent cardboard lining) inside the shipping container to protect the bags from temperature spikes and condensation.
With these practices, it is entirely possible to protect delicate floral and fruity profiles all the way to the roastery. In an upcoming article, we will discuss what sensory cues to look for during origin cupping sessions to identify coffees that might degrade prematurely.
