Flight or freight: What happens to coffee in transit?
Whether they are beans roasted locally or internationally, we all love our coffee. But, have you thought of how they might differ in quality or in other words, how might international shipping affect your coffee beans?
Here, we will look into understanding the different factors that need to be considered when coffee is being transported from one country to another.
Air vs sea shipping
The two main transport systems used in shipping coffee are air and sea freight. Green beans (raw coffee) are usually shipped via sea since their volume is usually considerably larger than roasted coffee, and the cost is also cheaper. One downside to sea travel is time. Generally, it will take more than a few weeks (or could go up to a few months) for the beans to reach its destination.
Coffee roasters will typically choose to use air freight when transporting roasted coffee beans in small quantities. Since the travel time is shorter, it allows the beans to reach its consumers in a considerably fresh condition.
What affects my coffee beans during shipping?
During transit, coffee beans are subjected to many factors that may cause irreversible damage to its quality. Here, we will discuss the three main ones, which are moisture content, relative humidity and temperature.
In the book, “Coffee: Growing, Processing, Sustainable Production: A Guidebook for Growers, Processors, Traders, and Researchers,” Jean Nicolas Wintgens explains that moisture content in a healthy green bean is typically between 11 to 14%. Those with moisture content higher than 15.5% are prone to pest attack while beans with 16.5% moisture content or higher are susceptible to mold attack. Coffee beans are hygroscopic in nature, meaning they will absorb moisture in air to reach an equilibrium with its surrounding.
Therefore, when green beans are in transit, there is risk of quality alteration since they are subjected to changes in surrounding humidity level, especially if the beans are not carefully protected.
Temperature is another contributing factor since a warmer environment increases the metabolic activity and respiration rate of coffee. Such activities produce carbon dioxide, heat and water which will cause quality deterioration as well as the loss of important chemical compounds that contribute to the aroma of coffee. Controlling for temperature changes can be especially challenging when you have a container full of coffee beans in the middle of the ocean, or when it is being left out in the docking area during transit.
When your roasted coffee bean travels by air, air pressure is something that needs to be taken into consideration. As you may or may not know, the one way valve on your coffee bag is the most important feature of packaging. It protects the coffee beans from exposure to oxygen while allowing the beans to degas (release carbon dioxide). Since sharp changes in air pressure (in the cabin) may damage the valve, this is another risk (albeit a small one) that your beans may be exposed to oxygen during transit.
Therefore, it is important to understand what could potentially happen to coffee beans when it is being transported, and take necessary precaution to lower down such risks. For example, careful packaging or having a good working relationship with green bean suppliers. Using hermetic GrainPro bags which are designed to protect green coffee can be particularly helpful too.
Disclaimer: This article discusses factors that can affect both green and roasted coffee beans, though, we think that green beans are more affected by moisture and temperature since they are living plant matters.
Jean Nicolas Wintgens, Coffee: Growing, Processing, Sustainable Production: A Guidebook for Growers, Processors, Traders, and Researchers