---
type: Organization
title: Cordwell Roastworks
description: A coffee roastery whose bar and R&D bench trains new brewers on extraction
  science and keeps a separate bench log for cold-brew experiments.
tags:
- coffee
- roastery
- brewing
resource: raw/brewing-science-notes.md
timestamp: '2026-07-16T15:03:02Z'
citadel_version: 0.3.0
---

Cordwell Roastworks runs a bar and an R&D bench where new brewers are trained.[^s1] It hands every new brewer an internal primer on extraction science — what extraction is, the numbers the [Specialty Coffee Association](specialty-coffee-association.md) publishes, and how grind, time, temperature, and water push a cup — as the "why" behind its recipes, and keeps a copy of it by the scale.[^s1]

Cordwell Roastworks keeps its cold-brew specifics in a separate immersion bench log rather than in the extraction primer.[^s2] That log is a dated R&D notebook run off "Bench 3" on an immersion rig, with readings taken on a calibrated refractometer, and its bench work defaults to Cordwell's own medium-roast "Slow Tide" bean unless a specific run says otherwise.[^s3] By the end of the first quarter of 2026 it had locked a house cold-brew spec — coarse grind, a 1:8 concentrate ratio, a 14-18 hour steep depending on temperature, and a stainless screen plus paper filtration step — detailed on [Coffee Brewing](../concepts/coffee-brewing.md).[^s4]

## Open Points

### Stir at 8 Hours and Extraction Yield
id: op-stir-at-8-hours-and-extraction-yield
- 2026-03-12: raised — does a gentle stir at t=8 h lift extraction yield without pulling silt into the cup? testing planned for the following week.[^s5]
- 2026-03-14: resolved — a single gentle stir at t=8 h raised concentrate TDS slightly (4.3% vs. 4.0% for an unstirred control) with no added astringency; adopted for batch-scale brews only.[^s6]

### Concentrate TDS vs. Steep Hours Curve
id: op-concentrate-tds-vs-steep-hours-curve
- 2026-03-12: raised — map concentrate TDS against steep time at 10, 12, 14, 16, and 18 hours into a single curve.[^s5]
- 2026-03-17: resolved — a room-temperature, 1:8 concentrate measured 3.1% TDS at 10 h, 3.5% at 12 h, 4.0% at 14 h, 4.1% at 16 h, and 4.2% at 18 h, plateauing past about 16 hours.[^s7]

### Decaf Cold Brew Residual Caffeine
id: op-decaf-cold-brew-residual-caffeine
- 2026-03-12: raised — whether the same cold-brew method, run on decaf beans, confirms a low residual caffeine level.[^s5]

## See also
- [Coffee Brewing](../concepts/coffee-brewing.md)
- [Specialty Coffee Association](specialty-coffee-association.md)

## Sources
[^s1]: [raw/brewing-science-notes.md](../../raw/brewing-science-notes.md), lines 3-6 — internal brew-lab primer, bar and R&D bench (ingested 2026-07-16)
[^s2]: [raw/brewing-science-notes.md](../../raw/brewing-science-notes.md), lines 6-7 — cold-brew specifics kept in a separate immersion bench log (ingested 2026-07-16)
[^s3]: [raw/cold-brew-notes.md](../../raw/cold-brew-notes.md), lines 3-4 — bench log identity (Bench 3, immersion rig, refractometer) and default "Slow Tide" bean (ingested 2026-07-16)
[^s4]: [raw/cold-brew-notes.md](../../raw/cold-brew-notes.md), lines 108-113 — locked house cold-brew spec (ingested 2026-07-16)
[^s5]: [raw/cold-brew-notes.md](../../raw/cold-brew-notes.md), lines 91-94 — open questions raised for the following week (ingested 2026-07-16)
[^s6]: [raw/cold-brew-notes.md](../../raw/cold-brew-notes.md), lines 96-98 — t=8h stir test result (ingested 2026-07-16)
[^s7]: [raw/cold-brew-notes.md](../../raw/cold-brew-notes.md), lines 100-106 — concentrate TDS steep curve, room temp 1:8 (ingested 2026-07-16)
