Stalled Fermentation Trouble Shooting Guide

[Bushman]

Written by Lampshade:
Stalled fermentation trouble shooting guide

Cause: Wrong temperature The optimum temperature for Baker's yeast is 75 to 95 degrees,
Fahrenheit or 24 to 35 Celsius. The optimum temperature for yeast strains (e.g. EC 1118) vary. Yeast go
dormant when the wash temperature is low and die when the wash temperature is too high.
Test: Measure the wash temperature.
Remedy: Adjust the wash temperature. If the wash is hot, allow it to cool or add cool water.
If the wash is cool move it to a warmer location, wrap it in a blanket, or provide heat.

Cause: Too acidic The wash pH should be between 3.6 and 6. The ideal pH is 5. Yeast go
dormant or die when the pH drops below 3.
Test: Measure the pH using ph strips (available from pool supply stores) or a ph meter
(available from the Internet).
Remedy: Raise the pH by adding calcium carbonate, potassium carbonate, sodium carbonate, or
5.2 pH stabilizer.

Cause: Too basic See "Too acidic."
Test: Measure the pH using ph strips (available from pool supply stores) or a ph meter
(available from the Internet).
Remedy: Lower the pH by adding lemon juice or citric acid.

Cause: Too much sugar The starting S.G.(specific gravity) should be below 1.09. Otherwise,
sugar content is too high, which weakens the yeast cell membranes. This also causes
the yeast to produce too much ethanol, which kills the yeast. At the very least, high
sugar washes produce off flavors.
Test: Measure the specific gravity with hydrometer (available from a brewing supply store).
Remedy: Lower the S.G by adding water or make a new wash with less sugar.

Cause: Soft water Soft water lacks vital minerals, like zinc and magnesium.
Test: Are you using a water softener. If not, ask for a water analysis from the water
provider.
Remedy: Bypass the water softener. Or, add minerals such as gypsum.