Most immersion brew methods require baristas to break a crust of coffee at some point during the brewing process. When cupping, the convention established by the Specialty Coffee Association is to break the crust 3–5 minutes after the pour. Our research into this process suggests that the highest extraction yields are achieved when the crust is broken after 5 minutes. Experiments by Barista Hustle into the effect of the crust of coffee on immersion brewing have revealed some unexpected results. You might expect that stirring the crust after 1 minute, which ensures all the grinds are fully submerged, would increase extraction — surprisingly, it doesn’t. Nor does leaving coffee sitting for as long as possible with the crust intact lead to maximal extraction. The fact is, there’s a sweet spot after 5 minutes, which the experiment demonstrates.
Immersion
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Immersion Prologue
- IM 0.01 Immersion Prologue
Variables in Immersion Brewing
- IM 1.01 Mixing
- IM 1.02 Layering — The Crust
- IM 1.03 Breaking the Crust
- IM 1.04 Layering — the Coffee Bed
- IM 1.05 Agitation
- IM 1.06 Filtration Media
- IM 1.07 Washing Reusable Filters
- IM 1.08 Decanting Coffee
- IM 1.09 Recap and Glossary
- IM 1.10 Comprehension Test
Extraction
- IM 2.0 What's in Chapter 2?
- IM 2.01 Diffusion
- IM 2.02 The No-Slip Boundary Condition
- IM 2.03 Erosion
- IM 2.04 Profiling Temperature and Time
- IM 2.05 Grind Size Distribution and Immersion
- IM 2.06 Overextraction and Underextraction
- IM 2.07 Recap and Glossary
- IM 2.08 Comprehension Test — Chapter 2
Static Immersion
- IM 3.0 What's in Chapter 3?
- IM 3.01 The History of French Press
- IM 3.02 Testing the Variables in French Press Brewing
- IM 3.03 Testing the Variables in French Press Brewing — Part 2
- IM 3.04 French Press Recipe
- IM 3.05 Jug Coffee
- IM 3.06 Jug Coffee Recipe
- IM 3.07 Recap
- IM 3.08 Comprehension Test Chapter 3
Pressurised Immersion
- IM 4.0 What's in Chapter 4?
- IM 4.01 AeroPress
- IM 4.02 Interview with Jeff Verellen, Two-Time World AeroPress Champion
- IM 4.03 The Impact of Plunging
- IM 4.03.1 How Much Pressure?
- IM 4.03.2 Turbidity
- IM 4.04 Upright, Inverted, or Both?
- IM 4.05 AeroPress Recipe with Jessica Sartiani
- IM 4.06 Syphon Coffee
- IM 4.07 The Science Behind Syphons
- IM 4.08 Experiments with Syphon Coffee — Part 1
- IM 4.09 Experiments with Syphon Coffee — Part 2
- IM 4.10 Recap
- IM 4.11 Comprehension Test — Chapter 4
Hybrids
- IM 5.0 What's in Chapter 5?
- IM 5.01 Steep-and-Release
- IM 5.02 Experiments with Steep-and-Release
- IM 5.03 Water First or Coffee First?
- IM 5.04 Playing with Drawdown Speeds
- IM 5.05 Recap
- IM 5.06 Comprehension Test — Chapter 5
Cezve / Ibrik
- IM 6.0 What's in Chapter 6?
- IM 6.01 The History of the Cezve
- IM 6.02 Interview with Sara Alali
- IM 6.03 Brass, Copper, Silver, Aluminium, Glass, or Steel?
- IM 6.04 Interview with Emir Ali Enç from Soy Türkiye
- IM 6.05 Raghweh and Serving Temperature
- IM 6.06 Experiments with Cezve Coffee
- IM 6.07 Grinding as Fine as Possible
- IM 6.08 Should I Preheat the Water Before Adding It to My Cezve?
- IM 6.09 When Should I Remove my Cezve from the Flame?
- IM 6.10 Recap and Glossary
- IM 6.11 Comprehension Test — Chapter Six
IM Baseline Testing
- IM 7.0 What's in Chapter 7?
- IM 7.01 Static Immersion Baseline
- IM 7.02 AeroPress Baseline Test
- IM 7.03 Cezve / Ibrik Baseline Test
- IM 7.04 Syphon Baseline Test
- IM 7.05 Steep-and-Release Baseline Test
- IM 7.06 Final Assessment
- IM 7.07 A Final Word