How long can I cold-retard a shaped sourdough?

12 to 18 hours is the sweet spot at 4°C. Below 12h the flavour boost is barely there; past 24h the dough loses spring as the gluten slowly degrades from lactic acid. Strong bread flour can take 36h cleanly; soft, lower-protein flour starts to slacken after 20h. Pull it out when the surface looks domed and a wet-finger poke fills back about halfway in 5 seconds.

Does my dough keep rising in the fridge?

Barely. Below 6°C, wild yeast activity drops by roughly 90% — your dough might gain 10-20% volume across the whole night, not the doubling you see at room temperature. What does keep working is the lactic acid bacteria and the enzymes in the flour, which is why the dough tastes deeper and the skin tightens overnight without ballooning.

Should I cold-retard before or after shaping?

After shaping, almost always. A shaped loaf in a banneton holds its form through the long cold and slices cleanly straight from the fridge — perfect for sharp scoring. Pre-shape retards (bulk in the fridge) work too, but you'll need to warm and shape the dough in the morning, and the bake window is tighter.

Why does cold-retarded bread taste more sour?

At fridge temperature, your wild yeast nearly stops but the LAB keeps producing acid, particularly acetic acid, which is the sharp vinegar note. Over a 16-hour retard the pH drops from around 4.5 to 3.8, and that drop is what you taste. Want less sour? Retard at 6-8°C instead of 4°C — the warmer cold still slows yeast but keeps the acid profile gentler.

Can I save an over-retarded dough?

If it's been more than 48 hours and the surface looks flat or wet, the gluten is too far gone for a tall boule. Don't panic — gently re-shape it as a low oblong, give it 30 minutes on the counter to come back to temperature, and bake hotter and shorter. You'll get a flatter, denser bread with intense flavour. Great for sandwiches; not great for Instagram.

Cold Retard: Why Your Best Loaves Sleep in the Fridge