1. Blending and Mixing
Blending means using different Arabica coffees or Robusta and then blending them together. Blending per species can be done before roasting if the screen size is in conformity.
Mixing means simply mixing 2 types of coffee species.
It is to be noted that blending is an important factor in securing consistent quality, as the overall taste is not dependent on one type of coffee classification. Should crop quality vary, the taste of a blend is then affected minimally as other types of coffee will support the overall taste.
A blend is each roasters intellectual property and the more attention is paid to blending, the less are the chances of competition being able to copy taste profiles and the higher the product can be differentiated in the market.
Blending coffee after roasting is certainly a plus as the roaster can focus on getting the best out of each bean before finding the right balance of beans.
This process is very simple, however needs great attention, as the ground size is an important factor for cup quality. The coffee is typically fed into a hub and out comes the ground coffee. The grinder can be adjusted to several sizes, from fine to coarse. Each brewing method has its own distinct particle size characteristics. Espresso is very fine to allow the pressurized water to penetrate in a way to extract most flavors and French press is the coarsest. Ground coffee should have 4% moisture and is hydroscopic, meaning it can easily take up moisture. This should be considered in countries where humidity is high.
This process is necessary to prevent ballooning of packaging, as coffee releases CO2 up to 10 days after roasting. The degassing time is in relation to roasting time so the longer the roasting time, the shorter the degassing time. In larger roasting facilities, degassing usually takes place in a silo.
Degassing occurs fast after grinding as the gasses can be released around 35% quicker when the bean is broken down into particles. So for whole bean coffee blends the degassing time is higher.
After degassing, the coffee is ready to be packed either whole bean or ground. Some roasters include one-way valve technology for whole bean coffee in order to save time with degassing. But not only that, the valve enables the CO2 to escape to the outside and stops oxygen entering inside of the packaging. Not only does the valve support the degassing process, it also keeps the coffee much fresher as it creates a semi-vacuum condition. Most producers pack coffee in pouches with rather thick material, using 105- 110 microns of 4 plastic layers to ensure freshness and to prevent creasing. Packaging is an important element of product presentation, hence an important part in marketing.