Roasting and combining coffee beans into distinctive blends can be challenging. Each type of bean in the blend needs to be carefully roasted to ensure consistency of color and taste of the final brew. Automatic sampling can help optimize sampling accuracy and repeatability in the coffee blending process, while ensuring a delicious cup every time.

The art of roasting coffee beans

Coffee starts as a green “bud” of the coffee plant. This bud is harvested and shipped to a roaster, where it’s heated into the fragrant, dark brown beans familiar to most people.

Roasting causes chemical changes as the beans are rapidly brought to very high temperatures, then quickly cooled to stop the roasting process. Most roasting machines maintain a temperature of about 550°F. When beans reach an internal temperature of about 400°F, they begin to turn brown and release caffeol, a fragrant oil locked inside the beans. They are then ready to be blended, ground and brewed.

A blended matter

Coffee blends are a popular choice among many coffee drinkers. Most roasters create blends because consumers want a consistent flavor profile year-round, giving drinkers a familiar favorite they know will always be available.

Combining beans into a blend often adds balance and complexity, while highlighting the best flavors of each type of coffee. Blends can contain up to five different coffees (or more) to create a distinctive yet balanced flavor profile.

Blends can be combined before or after roasting:

• Post-blending roasts each component bean individually and blends them after roasting. This helps roast all the component beans to bring out the best in each type of bean.
• Pre-blending involves mixing all the green components together and roasting them together. This generally improves consistency.

However, designing and roasting a blend that balances different flavors and roast profiles isn’t easy. It takes a lot of practice to know which coffees will blend well together, what percentages will work best in the blend, and what roast levels to use.

Testing from seed to cup

Coffee is repeatedly tested for quality and taste. Samples from a variety of batches and different beans are tasted daily to determine their characteristics and flaws, but also for the purpose of blending different beans or creating the proper roast. Most testing is done by a “cupper”, a professional coffee taster who evaluates the quality of coffee.

There are also coffee protocols recommended by the SCA Standards Committee and Professional Development Department that are guidelines to accurately assess the quality of the coffee.

Quality control through automatic sampling

Coffee blends present a challenge because the whole roasted coffee beans need to be sampled before and after they’re blended together. They should be consistent in color and taste and should be free of impurities. Automatic sampling can help optimize sampling accuracy and repeatability in the blending process to ensure the blend meets consumer expectations.

Representative samples can help coffee blenders:

• Determine product properties and composition
• Ensure quality control
• Improve return on investment
• Reduce operating costs
• Improve loss control

For example, Sentry recently worked with an OEM that creates coffee grinders and provides system integration for coffee processes. Together, we developed a custom sampling application for coffee blends to sample whole roasted coffee beans after blending. 

In this process, the batch was dispatched into the hopper and the automatic sampler provided a composite sample to ensure the beans were properly roasted. The variety of beans, roasted separately, were combined to create a custom blend. Each bean had a different roasting property and needed to be sampled together to ensure the quality of the blend and roasting prior to packaging and/or grinding.

Through reliable, accurate and repeatable sampling coffee producers receive real-time data to continue to customize blends and increase consumer confidence and caffeination.

Ready to learn more? Contact us at +1-262-567-7256, or complete our online contact form for more information on using a customized sampling solution for coffee beans and blends.