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How Long Does Sourdough Last? Does it Go Bad?

Sourdough is one of the oldest bread-making techniques still in use today, with history dating back to ancient Egypt.

The bread consists primarily of flour, water, and a sourdough starter.

But how long does sourdough last, and can it go bad?

Like many food products, sourdough does have a shelf life and can go bad, but it is more resilient than other bread because of its natural acidity and lower pH level.

The length of time that sourdough can remain good varies, depending on multiple factors.

What is Sourdough?

Sourdough is a type of bread that uses natural fermentation to leaven the dough, rather than using commercial yeast. It is made using a combination of flour and water and a live culture of wild yeasts and bacteria.

The sourdough bacteria produce lactic acid, which gives the bread its distinct tangy flavor and helps keep it fresh for longer periods. The lactic acid bacteria and yeast work together in symbiosis, feeding on the flour and producing carbon dioxide gas, which leavens the dough.

Sourdough loaves are dense, with a thick, chewy crust, and an airy, moist crumb with irregular holes. Because sourdough bread is created through the process of natural fermentation, it is also easier to digest than bread made with commercial yeast.

How Long Does Sourdough Last?

The shelf life of sourdough bread depends on many factors, including the method of preparation, storage, and the percentage of sourdough used. Sourdough bread with higher acidity content tends to be more resistant to mold growth and bacteria due to the acidity, and thus, it stays fresher for longer.

How to Store Sourdough?

Proper storage plays a crucial role in determining the shelf life of sourdough bread. Once it’s baked, it must be stored correctly to maintain the bread’s quality and freshness. Improper storage can cause the bread to spoil or stale before its time.

Here are some ways to store sourdough bread:

  • Bread Box: A bread box can be useful if you are storing sourdough bread for a day or two. The bread box should have ventilation to prevent the bread from getting damp, which can increase the risk of mold growth.
  • Paper Bag: Sourdough bread retains better in a paper bag than a plastic bag because it allows excess moisture to escape and prevents the bread from becoming soggy, which can encourage mold growth.
  • Freezing: Sourdough bread can be kept in the freezer for up to three months. The bread should be wrapped in plastic wrap or aluminum foil, then stashed in a freezer bag or container to preserve its texture.

How to Tell if Sourdough Has Gone Bad?

Sourdough bread can remain edible beyond its best-before date, but it can still go bad if not correctly stored or exposed to a conducive environment.

Below are some signs that your sourdough bread is bad:

Mold or Bacteria Growth

Mold or bacteria growth is the most apparent indication that sourdough bread has gone bad. Tiny spots or patches of green, black, or white growing on the surface of the bread are a sure indication that the bread is not worth eating.

Stale Smell and Taste

When bread goes bad, it tends to develop a stale or moldy smell. You might also detect signs of bitterness, making it less palatable to consume.

Stale Appearance

If your bread has moisture content, the mold growth rate is higher, which causes the bread to have a spongy, uneven texture, and a pale appearance.


The presence of cracks on the surface of the bread, especially if it’s a single, large crack, is a strong indication of staleness and a possible end to its shelf life.

How Long Does Sourdough Last Unopened?

Sourdough bread will last around four to five days unopened on the counter, depending on the humidity levels in the air. After that, the bread will begin to lose freshness and texture and become stale, but it is still safe to consume for a few more days.

Refrigerating an unopened sourdough bread may extend the shelf life to around seven to ten days as a valuable contributor to keeping the bread fresh. Refrigerating sourdough will slow the rate of mold and bacterial growth, but it will also stale the bread quickly as it will speed up the starch’s recrystallization process if it’s not appropriately stored.

How Long Does Sourdough Last Opened?

Sourdough bread lasts longer if stored correctly at room temperature, which can be up to ten days. The crust can become stale and hard, but it still can be eaten.

Once you cut into the bread, it will start to stale within two to three days, but it can last longer if you store it optimally in the fridge or freezer.

You must store the bread in a sealed container or bag to prevent excess moisture buildup, which can increase the rate of mold growth and cause the bread to become sticky or develop a sour odor.


Sourdough bread is a unique, natural, and healthier bread variation that possible through the activity of beneficial bacteria and yeasts.

Sourdough, with its natural acidity and lower pH level, resists mold and bacterial growth, making it more resilient than traditional bread. Properly stored sourdough can last up to ten days at room temperature and several months in the freezer.

Always keep sourdough in a paper bag, bread bin, or refrigerator in a tightly sealed container or bag to preserve its freshness and texture. Check for signs of staleness, mold, or bacteria growth before consuming sourdough bread. If in doubt, it’s better to be safe than sorry and dispose of the bread.

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Jenny has always been passionate about cooking, and she uses her platform to share her joy of food with others. Her recipes are easy to follow, and she loves giving tips and tricks to help others create their own unique culinary creations.