Coffee consultant and author Scott Rao joins Decent Espresso to explore how flow rate and roast level shape the taste of espresso. Using the DE1 machine, Scott compares a standard 2:1 espresso with an Allongé—both brewed from the same light-roast washed Typica—and explains why lighter roasts often shine with higher flow rates, while darker roasts benefit from shorter, gentler extractions.
Along the way, Scott covers:
Why lighter roasts can handle (and benefit from) more water through the puck
How roast degree affects extraction yield and solubles
The differences between Allongé, Blooming Espresso, Turbo shots, and traditional 2:1 ratios
Tips for reducing channeling, including paper filters and upgraded shower screens
How flow profiling on the DE1 makes high-flow extractions more forgiving
Learn more about Scott Rao
Chapters
00:00 – Introduction & session overview
00:21 – Serving the first espresso (2:1 ratio)
00:39 – Roast color, weight loss & development levels
01:25 – How flow rate affects light vs. dark roasts
02:10 – Shot length and managing bitterness in dark roasts
02:38 – Myth: Dark roasts are easier to extract
03:45 – How roast degree changes solubles & extraction potential
04:22 – Roast styles in Northern vs. Southern Italy
04:50 – Allongé & Blooming profiles on the Decent Espresso machine
05:35 – Why Allongé highlights acidity and fruity flavors
05:58 – Blooming Espresso: extraction yields & profile behavior
07:00 – Roast weight loss ranges: light to very dark
07:35 – Risks & benefits of high-ratio shots like Allongé
08:23 – Demo setup: serving the Allongé
08:42 – Paper filter tips for reducing channeling
09:43 – How grind size & flow rate change extraction dynamics
10:50 – Transport vs. diffusion in coffee extraction
11:33 – Defining “easy to extract” & bean origin differences
12:28 – Why Scott keeps recipes consistent across coffees
13:38 – Scott’s Montreal café experience with Allongé
15:00 – How the Decent makes Allongé easier & more consistent
15:38 – Timing-based flow profiling & adaptive shot control
16:12 – Allongé tasting notes & final thoughts
tag:scottrao tag:rao tag:allonge tag:blooming tag:decon tag:decon2025 tag:italy tag:roastcolor
