Step 2 — Fermentation

02 Process Step 2 — Fermentation: Ancestral — Método Alquímico

Process Summary

Single continuous fermentation in deposit, transferred mid-fermentation to bottle. Indigenous yeast only. No SO₂. No temperature intervention beyond natural cellar ambient (14–16°C). The fermentation that begins in the 100L stainless deposit is the same fermentation that creates the perlage in the bottle.

Process Stages

1. Day 0: Clean must at 8–10°C after débourbage
2. Day 1: Natural ramp to 14–16°C; indigenous fermentation initiates
3. Day 1–3: Non-Saccharomyces lead (Hanseniaspora, Lachancea, Candida)
4. Day 3–7: Indigenous *Saccharomyces cerevisiae* establishes dominance
5. Day 7–14: Active fermentation; density drops from ~1089 g/L
6. Day 14–21: Critical monitoring window — density check 2–3×/day as bottling target approaches
7. Bottling point (target density 1008–1010 g/L): still-fermenting cloudy wine transferred immediately to sparkling bottles, crown-capped
8. In-bottle fermentation completes over subsequent weeks; CO₂ trapped; pressure develops to 6.0 bar

Five Levers of Control (this step)

• Time: Bottled at exactly 24 g/L residual sugar — the critical control
• Temperature: 14–16°C deposit; cool start preserves esters and selects indigenous succession
• Oxygen: Strictly anaerobic deposit; master lever for high-pH AAB control
• Extraction: Zero (whole-cluster press already done)
• Vessel: 100L stainless "siempre lleno" deposit, then sealed bottle

Assets