How long can I leave a sourdough starter unfed in the fridge before it dies or goes bad?

Question

How long can a sourdough starter be left unfed in the fridge? Find out the limits before your starter goes bad or becomes too weak to revive easily.

Answer 1

A sourdough starter can typically survive unfed in the refrigerator for 1-2 weeks without significant issues. After that, it will become increasingly acidic and weak, potentially requiring multiple feedings to revive.

Detailed Explanation:

When you refrigerate your sourdough starter, you're essentially slowing down the fermentation process. The cold temperature significantly reduces the activity of the yeast and bacteria. However, they don't stop completely. They continue to consume the available starches and produce acids, just at a much slower rate.

Here's a breakdown of what happens over time:

1. First Week: The starter remains relatively stable. You might see a layer of liquid (hooch) forming on top, which is a sign of fermentation. This is normal and can be poured off or stirred back in.
2. Second Week: The starter becomes more acidic. The hooch layer might be darker and more pronounced. The yeast activity will be further reduced.
3. Beyond Two Weeks: The starter becomes increasingly acidic and depleted of nutrients. The yeast and bacteria may start to die off. It will likely require several feedings to revive it to its former strength. If you see mold or a pink/orange discoloration, discard the starter.

To revive a neglected starter, discard all but a tablespoon or two, and then feed it regularly (every 12-24 hours) with equal parts flour and water until it doubles in size predictably after each feeding. This may take several days.

Pro Tip:

Before refrigerating your starter for an extended period, feed it well. A well-fed starter will have more resources to survive longer in the fridge. Also, consider freezing a portion of your starter as a backup. Frozen starter can be revived, although it may take a bit longer than refrigerated starter.