Good to know. Thank you Deven
Did you think that was the end?
http://espressoitaliano.org/ (under construction)
The Craft and Science of Roasted Coffee, by Ted Lingle https://books.google.com/books?id=HURkCQAAQBAJ&pg=PA182&lpg=PA182&dq=Ted+Lingle’s+work+on+the+flavor+chemistry+of+coffee&source=bl&ots=E013qqJZgD&sig=6qv4W4TKg1rGBQ74Fuq1p2UMNWA&hl=en&sa=X&ved=0ahUKEwiDm7jks6DYAhVKRyYKHRlzAy8Q6AEIOzAD#v=onepage&q=Ted%20Lingle’s%20work%20on%20the%20flavor%20chemistry%20of%20coffee&f=false
Listening suggestions: Tiesto Majik 1, https://www.youtube.com/watch?v=Rw0iIsB0_SY
Effect of Fan Speed
Thank you Mr.Librarian (@Geoff_IKAWA - we neeeed a librarian badge lol )
It would take me really some time to go through those links …
Seriously awesome! It’s great to have all these resources, and all in one place!
“Green beans smell green-earthy, so they ust be heat treated in a process called roasting to bring about their truly delightful aroma. Roasting in the temperature range of 200-250C causes profound change The beans increase in volume (50-80%) and change their structure and color. The green is replaced by a brown color, a 13-20% loss in weight occurse, and there is build-up of the typical roasted flavor of the beans. Simultaneously, the specific gravity falls from 1.126-1.272 to 0.570-0.694, hence the roasted coffee floats on water and the green beans sink. The horny, tough and difficult-to-crak beans become brittle and mellow after roasting.
Four major Phasses are distinguished during the roasting process; drying, development, decomposition and full roasting. The initial changes occur at or above 50C when the protein in the tissue cells denatures and water evaporates. Browning ocurs above 100C due to pyrolisis of organic compounds, accompanied by swelling and an inital dry distillation: at about 150C there is a release of volatile prodicuts (water, CO2, CO) which results in an increase in bean volume. The decompositon phase, which begins at 180-200*C, is recognizable by the beans being forced to pop and burst (bursting by bracking along the grooe or furrow); formation of bluish smoke; and the release of coffee aroma. Lastly, under optimum caramelizaiton, the full roating phase is achieved, during which the moisture content of the bean drops to its final level of 1.5-3.5%. The roasting process is characterized b a decrease in old and formations of new ompunds…The running of a roasting process requires skill and experience to achieve uniform color and optimum aroma development and to minimize the damage through over-roasting, scourching or burning.”
(Food Chemisty by: Professor Dr.-Ing. H.-D. Belitz, Professor Dr.-Ing. W. Grosch)
Phases of roast, Colour changes, how do you interpret them?
How do you troubleshoot poor roasts?
nice! hadn’t noticed this thread yet, but the accumulation of knowledge is very much appreciated!
+1: give the man a badge!!
found this little nugget that shines a whole lota light. Maybe this gives some insight confirming my suspicions that the Pro is about 80*F cooler than the temp required from the Home.
Charge Temp, Rate of Rise, Drop temp
Addition: This is the link for Dr. Yeretzian et al, research paper
The magnanimous Rob Hoos writes about heat transfer in a roaster and I think alludes A LOT to the IKAWA
Another Very long paper but filled with answers some I was looking for, others I wasn’t.
Effects of Origin and Treatment of the Roasting Process on the Aromatic and Sensorial Composition of Coffee By Giovanni Mastronardi
Another very interesting article measuring porosity during the roast, I picked this up from a great thread on the Thermodynamics of first crack on Home-barista.com (https://www.home-barista.com/home-roasting/thermodynamics-of-first-crack-t52552.html)
An informative youtube channel looking into professional side of coffee business and production.
An interesting thing to think about: What coffees are, and what they might be like, when tasting…
Tom from Sweet Maria’s how to choose a coffee and in a way tasting coffee
George Horwell, talking about the variations and all things when it comes to drinking/tasting/being coffee. This 4 part series is certainly worth the time. enjoy!
“Lighten Up: Creating the Perfect Light Roast” by Willem Boot
Not exactly anything eye opening, but an interestingly short, informing, read.
Title: Fixing Underdeveloped Roasts: Millard vs Post FC Development
Although we are on a different machine, calibrating what is being discussed to the Ikawa is still very usefull and certainly good fruit for thought.