How Roasting can make (or break) coffee

Summary

In this insightful session at the Wollongong roastery, Boris delves into the art of coffee roasting, explaining the critical balance between raw coffee quality and roasting technique. He discusses the roasting process, highlighting the role of drum and airflow roasters, and key chemical reactions like endothermic and exothermic phases, including first crack and the Maillard reaction. Boris emphasizes the importance of understanding how different coffee seeds react to heat, cautioning beginners against merely imitating others. This engaging exploration offers valuable tips for aspiring roasters and fosters a deeper appreciation for the craft behind a perfect cup of coffee.

Takeaways

• ☕ Roasting is crucial for unlocking the unique flavors of coffee; it can enhance or diminish quality.
• 🔥 Two main roasting methods are used: drum roasters and airflow roasters, each employing different heating techniques.
• 🌀 In a drum roaster, beans are heated through both direct contact with a heated drum and heated air.
• ❄️ Proper cooling of the coffee after roasting is vital to stop the roasting process effectively.
• 📊 The roasting process follows a temperature curve, indicating the stages of heat absorption and energy release.
• 🔄 An endothermic reaction occurs as beans absorb heat until they reach critical mass, leading to an exothermic reaction.
• 🥖 The Maillard reaction, responsible for caramelization, is key to developing flavor during roasting.
• 🤔 Both high-quality green coffee and skillful roasting are essential for achieving excellent flavor.
• 🔍 New roasters often make mistakes due to a lack of understanding of how different coffee seeds react to heat.
• 📚 Learning to use your specific roaster and understanding its idiosyncrasies is crucial for successful roasting.

Q & A

What is the significance of roasting in coffee production?

Roasting is crucial as it can either enhance the unique flavors developed by the producer or diminish them to blandness.

What equipment is typically used for roasting coffee?

Coffee is usually roasted using either a drum style roaster or an airflow roaster.

How does a drum roaster operate?

In a drum roaster, coffee beans are placed in a spinning drum heated by gas burners, allowing the beans to roll and absorb heat from both the drum and heated air.

What happens when coffee is dropped into the cooling tray?

When coffee is dropped into the cooling tray, it isn't finished roasting; this process is vital to halt the roasting at the desired time and lock in flavors.

What is the turning point in the roasting process?

The turning point is where the temperature curve of the coffee seeds plateaus before it begins to rise again, indicating a shift from endothermic to exothermic reactions.

Can you explain the difference between endothermic and exothermic reactions in coffee roasting?

An endothermic reaction involves the coffee absorbing heat, while an exothermic reaction occurs when the coffee releases energy, marked by the first crack.

What is the Maillard reaction and why is it important?

The Maillard reaction is a series of chemical reactions that occur when sugars are caramelized during roasting, contributing to flavor development and complexity.

Is the quality of green coffee or the roasting process more important?

Both are important; a skilled roaster can improve average coffee, but starting with high-quality green coffee is essential for exceptional results.

What are some common mistakes made by novice roasters?

Common mistakes include not understanding that different coffee seeds react differently to heat and failing to learn the specifics of their roasting equipment.

What advice does Boris give to new roasters about learning their craft?

Boris advises new roasters to familiarize themselves with their specific roaster and not to simply copy others' methods without understanding their own equipment.