2.1°C
COLD BREW

Extracted at 2°C. For 22 Hours.

Init
22:00:00
Extraction Duration

Seventy-nine thousand two hundred seconds. The duration is not arbitrary — it is the precise window between under-extracted bitterness and over-extracted astringency at 2 degrees Celsius. Time is the single variable that changes everything.

Extraction Protocol

Process Timeline

Water source
TDS: 75 ppm pH: 7.2
Stage 01 / 06
Water Source

Alpine spring water filtered to 75 ppm TDS. pH adjusted to 7.2. Chilled to 3°C before contact with grounds.

Coffee filter
Filter: 20μm Temp: 3°C
Stage 02 / 06
Filtration

20-micron stainless mesh. No paper filtration — oils are the carrier of aromatic complexity.

Coffee grind
Grind: 900μm EK43 setting 9
Stage 03 / 06
Grind

900-micron median particle size. Coarser than espresso, finer than French press. Surface area calculated per batch weight.

Cold steep
Temp: 2.1°C 22:00:00
Stage 04 / 06
Steep

Full immersion at 2°C for precisely 22 hours. Temperature monitored every 15 minutes via IoT sensor array.

Press filter
Pressure: 2 bar Yield: 88%
Stage 05 / 06
Press Filter

2-bar gentle press through 20μm stainless steel. 88% yield retained. Final filtration at 5μm removes residual fines.

Package seal
Batch #: 00847 N₂ sealed
Stage 06 / 06
Package

Nitrogen-flushed glass bottles. Batch number laser-etched. Every unit traceable from bean to bottle.

Product Matrix

The Spectrum

Expression 01
Standard
Multi-origin blend · 22h · 2°C
TDS Concentration52%
1.28
TDS %
Expression 02
Reserve
Single-origin Ethiopia · 22h · 1.5°C
TDS Concentration72%
1.46
TDS %
Expression 03
Concentrate
Colombia Gesha · 26h · 2°C
TDS Concentration91%
2.12
TDS %
Single-Origin Programme

Origin Series

Ethiopia Yirgacheffe
ETH · 2024
Ethiopia Yirgacheffe
Elevation 2,100 m
Process Natural
TDS Target 1.46%

Jasmine, blueberry, citrus blossom. The floral complexity holds through 22 hours at 1.5°C in a way that would be destroyed by heat.

Colombia Gesha
COL · 2024
Colombia Gesha
Elevation 1,900 m
Process Washed
TDS Target 2.12%

Bergamot, stone fruit, clean acidity. Concentrated expression only. Used in 26-hour protocol for maximum extraction at density.

Kenya AA
KEN · 2024
Kenya AA Kirinyaga
Elevation 1,780 m
Process Washed AA
TDS Target 1.38%

Black currant, tomato, intense berry acidity. The cold process tames the aggressive acidity while preserving the fruit character.

Research Archive

Lab Notes

EXP-047
Rwanda Steep at 1°C: Beyond the Standard Protocol

At 1°C we observed a 34% reduction in caffeine extraction while retaining 91% of volatile aromatic compounds. The data suggests a viability window below standard cold brew temperatures.

Feb 14, 2024 8 min read
EXP-052
Particle Size vs. Extraction Rate at Sub-4°C Temperatures

An 18% reduction in grind particle size (from 900μm to 740μm) yielded a 23% increase in extraction yield at 2°C — but introduced significant astringency markers above 22 hours.

Mar 2, 2024 11 min read
EXP-061
Water Mineral Content and Cold Brew Mouthfeel: A Systematic Study

Comparing five water mineral profiles (50–200 ppm TDS) across identical Ethiopia Yirgacheffe batches. Magnesium concentration above 10 ppm consistently enhanced sweetness perception.

Apr 18, 2024 14 min read
Join The Extract