Every week, we transform hundreds of pounds of raw, green coffee beans into the aromatic, flavorful roasted coffee that our customers love. But what actually happens during roasting? And how do the decisions our roaster makes affect the flavor in your cup? Let us take you inside our roastery for a behind-the-scenes look at the art and science of coffee roasting.
Our Roaster: The Probat
At the heart of our operation is a Probat drum roaster, a German-engineered machine that has been the gold standard in specialty coffee roasting for over a century. Our particular machine can roast up to 25 pounds of coffee at a time, which is considered small-batch in the industry. This small batch size allows us to monitor and control each roast with precision, ensuring consistency and quality.
Green Coffee: Where It All Starts
Raw, unroasted coffee beans are actually seeds of the coffee cherry fruit. They are dense, hard, and have a grassy, vegetal smell -- nothing like the aromatic coffee you know. These green beans can be stored for months without losing quality, which is why coffee can be shipped around the world from growing regions without degradation.
When we receive a new lot of green coffee, the first thing we do is sample roast small quantities at different profiles to discover how the bean responds to heat. This cupping process helps us develop the ideal roast profile for each origin -- the specific combination of temperature, airflow, and time that brings out the best characteristics of that particular coffee.
The Roasting Process
Roasting unfolds in distinct stages. In the first phase, called the drying phase, the beans absorb heat and begin to lose moisture. The beans change from green to yellow and give off a grassy, bread-like aroma. This phase typically lasts 4-5 minutes.
Next comes the Maillard reaction phase, where sugars and amino acids in the beans begin to react, creating hundreds of new flavor compounds. The beans turn from yellow to light brown, and the aroma shifts to something like toasting bread or baking cookies. This is where the magic of flavor development really begins.
First crack is the most critical moment in the roast. At around 385-400 degrees Fahrenheit, the beans audibly crack -- similar to the sound of popcorn popping -- as internal moisture becomes steam and pressure builds. This marks the transition from a light roast to a medium roast. Everything from this point forward is a matter of seconds and degrees, and the roaster must make rapid decisions about when to end the roast.
For our lighter single-origin roasts, we typically end the roast shortly after first crack, preserving the bright, fruity, and floral characteristics of the bean. For our espresso blend, we extend the roast further into the development phase to create the body, sweetness, and caramel notes that pair beautifully with milk. If roasting continues to second crack (around 440 degrees Fahrenheit), the coffee enters dark roast territory, where roast character dominates over origin character.
Quality Control
After every roast, we cup the coffee to evaluate it against our standards. Cupping is a standardized tasting protocol used across the specialty coffee industry. We evaluate each coffee for aroma, flavor, acidity, body, sweetness, balance, and cleanliness. Only batches that meet our quality standards are approved for sale.