What You Need to Know
Malted barley provides amylases that hydrolyze starches into fermentable sugars during a 2‑3 h saccharification step at 30‑35 °C. Wild Saccharomyces yeasts then convert these sugars into ethanol and CO₂, while lactic‑acid bacteria produce lactic acid, giving the beer a mild sour note. Oxidation of the finished beer can occur if the sealed clay jars are exposed to air or high temperatures.
The Science
Primary Reaction
Starch → fermentable sugars (via amylase) → ethanol + CO₂ (yeast) + lactic acid (bacteria)