class: title, center, middle # Roasting: Foundation \#CaffeinatedTraining \#OilSlickCoffee
@michael.c.wright
youtube.com/c/MichaelCWright
OilSlickCoffee
Presented: February 26th, 2019 Host:
5758 Coffee Lab
Location: Bandung, Indonesia .footnote[ Press "h" for keyboard shortcuts for this presentation] --- #Housekeeping * Silence your phones * Bathrooms located... * Exits located... --- class: pic ![drum roaster diagram](https://oilslick.github.io/caffeinated.training/images/roaster-diagram.jpg) --- # Three Burner Types Atmospheric burner (gas burner) Electric burner (like toaster oven) Infrared burner (ceramic plates in BBQ grill) ??? Electrical burners possible on small (batch size 12 and less) roasters. Electrical heating elements are slow but are fine for roasting. Electricity always drives motors and general control circuits. --- # Heat Transfer Methods Convective Conductive Radiative Related: Endothermic Exothermic ??? Two most common: convective and conductive. Convective involves moving air. Conductive requires physical contact and a temperature gradient. Drum rotation important here Radiated heat example: the light emitted from a red-hot heating element in a toaster Keywords: Convection Conduction Endothermic Exothermic --- # Roasting Plant Safety **Three areas of concern:** Fire Ventilation Personal safety * Create an emergency plan ahead of time * Discuss the plan with everyone * Create a cleaning + maintenance plan * Regularly review procedures and plans ??? Given a long enough timeline, everyone will experience a fire. Personal safety examples: loading coffee (heavy weight over head, maybe on stool, etc) Smoke in roasting (ventilation, as smoke does escape the roaster into the room) Personal hazard areas: Green coffee storage Roasting Packaging, production shipping Keywords: Airflow, chimney Chaff. Chaff collector Fire extinguisher (water vs. CO2) Fire in the chimney Fire in the drum Stirring device/agitator/cooling bin (long, draping clothes) --- # Roaster fires 1. Shut off gas (or element if electric) 2. Keep drum rotating 3. Don’t open roaster doors 4. Don’t eject beans --- # Personal Safety Concerns **Four areas of concern:** * Green coffee storage * Roasting * Packaging, production * Shipping What are some concerns in these areas? --- # Fire Classifications * Class A Ordinary items (wood, paper, plastic, rags) * Class B Flammable Liquids * Class C Electrical equipment --- # Roaster Cleaning & Maintenance * Remove chaff often (fuel source for fire) * Know where chaff collects in your roaster * At least daily, more for “chaffy” beans * Keep ducts clear/clean (creosote & chaff) * Keep moving parts lubricated (food grade grease) * Follow manufacturer’s manual and recommendations --- # Physical changes in the bean * Dries out * Progressively darkens * Becomes increasingly brittle * First Crack * Size can increase 30 - 100% * Second crack * Eventually oil seeps out (especially beyond second crack) * Sometimes get divots (can be a roast defect) * Rapid cooling (≤ 4min) to halt chemical reactions (changes) --- # First Crack and Second Crack * Every *successful* roast has a first crack * First crack is the result of rapid release of pent-up vapor/steam pressure and CO2 * Not all roasts reach second crack (operator’s preference) * Exothermic flashes as escaping heat affects environment --- # Roast Data Measurements that can be collected from green and roasted coffee: 1. Green: batch weight 2. Green: bulk density 3. Green: volume 4. Green: screen size 5. Green: moisture content (acceptable range for Specialty?) 6. Roasted: color 7. Roasted: weight\* 8. Roasted: bulk density\* 9. Roasted: volume\* Cupping data should be associated with roast profile for post-roast analysis. .footnote[ \*Calculate percent changes for these attributes] --- # Label the following on a typical roast profile Charge Turning Point Color change: green to yellow First crack Second crack Roast End ![example roast profile](https://oilslick.github.io/caffeinated.training/images/example-roast-profile.jpg) --- # Roast Progression * Lighter roasts highlight (preserve) acidity, enzymatic flavors/aromas * Darker roasts emphasize chocolatey, nutty, bitter flavors/aromas --- # Temperature Midway Point ≈ 75 Agtron * New concept * Generates easy color to work/train with * Not meant to be a standard or a sweet spot regarding end product ![tmp equation](https://oilslick.github.io/caffeinated.training/images/tmp-equation.jpg) --- class: center, middle ## Value 4 Value If you found this content useful, please consider [supporting my work](https://oilslickcoffee.com/support/?utm_source=caffeinated-training&utm_medium=blog&utm_campaign=support). I charge no set fee or price for providing this. You can help keep information like this openly accessible by matching the value you received in the content; value 4 value. [Ko-fi](https://ko-fi.com/Z8Z8LX14) **/** Bitcoin Wallet: 32SW9kcAsJdZvQKBazhLUZBSD9YS8DDqe8
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