Notes on Coffee Roasting Presentation by Kat Malheim

Introduction

• Presenter: Kat Malheim (RoasterKat on Instagram and YouTube)
• Topic: Coffee Roasting
• Title of Talk: "Roasting Isn't That Hard"
• Objective: To demystify and simplify the coffee roasting process for roasters, baristas, and consumers.

Overview of Roasting

• Roasting Definition: Applying heat to raw coffee beans to create physical and chemical changes.
• Simplicity: Turning coffee brown by making it hot.
• Challenges:
  • Complicated concepts and contrasting opinions in the roasting community.
  • Importance of understanding green coffee, machines, and tasting.
  • Each coffee and machine is different, requiring tailored approaches.

Key Points of Roasting

Physical Changes During Roasting

1. Color Change: Coffee transitions from greenish to a range of browns.
2. Size Increase: Beans can increase in size by 20-50%.
3. Mass Decrease: Moisture loss from approximately 10-12% to about 2.5%.
4. Brittleness & Porosity: Beans become more brittle and porous, enabling grinding.
5. Oil Migration: Oils may migrate to the surface in darker roasts.

Chemical Changes During Roasting

• Maillard Reaction: Non-enzymatic browning; reacts carbohydrates with amino acids, creating new flavors.
• Strucker Degradation: Produces aroma and flavor compounds.
• Sugar Caramelization: Breakdown of complex carbohydrates into simpler sugars.
• Volatile vs Non-volatile Compounds:
  • Volatile compounds contribute to aroma.
  • Non-volatile compounds are stable, affecting flavor.

Core Focus Areas for Roasters

1. Green Coffee: Understanding attributes (variety, density, size, processing).
2. Roasting Machine: Knowing machine specifications and how various coffees respond to it.
3. Flavor & Results: Importance of tasting and understanding the end results of roasting.

Green Coffee Characteristics

• Attributes to consider:
  • Variety, density, size, processing method, intrinsic potential.
• Simplifying focus to key attributes helps in approaching new coffees with confidence.

Suggested Exercises

Exercise 1: Sample Roasting

• Roast a coffee in three ways:
  1. Standard roast.
  2. Shorten roast by 10-20 seconds.
  3. Extend roast by 10-20 seconds.
• Taste and compare results to learn about the coffee's development.

Exercise 2: Understanding Your Machine

• "Hot and Heavy" exercise:
  1. Load machine to full capacity and roast normally.
  2. Roast at 50% capacity with maximum heat.
  3. Taste results and observe differences based on load and heat application.

Exercise 3: Palate Development

• Triangulation Exercise:
  • Brew three cups (two from the same coffee, one different).
  • Identify the odd cup.
  • Helps develop ability to differentiate flavors.

Occupational Hazards in Roasting

• Importance of safety discussions.
• Acute Dangers: Cuts, bruises, accidents with equipment.
• Chronic Conditions: Green coffee allergies, muscle strains, tennis elbow.
• Mental Health: Addressing burnout and maintaining engagement in the work.

Conclusion

• Roasting is about more than just applying heat; it's about developing skills, understanding coffee, and tasting.
• Encouragement to experiment, taste, and question techniques in roasting.

Q&A Session

• Engaged audience with questions about roasting experience and competition.
• Encouraged participants to follow her on social media for more insights on coffee roasting.