Bought a sourdough starter or bag of bread flour but not quite ready to bake? No stress.
One of the best parts of using dried sourdough starter flakes is their long shelf life. You don’t have to activate them straight away. In fact, you can store both your dried starter and bread flour for months or even years with no fuss, as long as you store them the right way.
This guide will walk you through how long your ingredients last, how to tell if they’re still good, and how to store them properly so they’re ready when you are.
Short Term: What to Expect in the First 12 Months
If you’ve purchased a starter kit or a pack of flakes recently, you’re in the best window to activate them.
Dried starter flakes
Your dried sourdough starter is best activated within the first 12 to 18 months. During this time, the wild yeast and friendly bacteria inside are still dormant but very much alive. When rehydrated and fed properly, they will spring back into action with ease.
Beginner tip: The sooner you activate it, the faster and easier it usually is to get it bubbly and baking-ready.
Bread flour
High-quality bread flour can last up to 12 months unopened if kept in a cool, dry place. You might be able to use it beyond that, but for best performance, especially for sourdough, we recommend using it within the first year.
How to store them short term
- Keep both starter flakes and flour sealed in their original packaging or transfer to airtight containers
- Store in a dark pantry or cupboard away from moisture and direct heat
- Avoid storing flour near spices or strong-smelling items, as flour can absorb odours over time
Medium Term: Can It Last Beyond a Year?
Yes, especially the dried starter.
Dried starter shelf life
Even after 18 months, your starter flakes can often still be revived successfully, provided they have been kept cool, dry and sealed.
Here’s what to look for:
- Dryness: The flakes should feel brittle, not soft or damp
- Smell: There should be no musty, sour or off smell. Neutral is fine
- Appearance: Light brown or beige is normal. If the flakes have gone very dark or have visible mould or clumping, it's best to replace them
If the flakes pass those checks, they are probably still good to go.
Bread flour after 12 months
Flour can last longer if stored in ideal conditions, but it may lose some of its strength or flavour over time. This matters more in sourdough baking where the flour feeds the starter.
To check if your flour is still usable:
- Look for signs of clumping or a stale smell
- If it smells fresh and isn’t discoloured, it’s likely fine
- Sift it before use if it’s been sitting for a while to break up any compacting
Beginner tip: Store flour in a sealed container in the fridge or freezer if you live in a hot or humid climate. Just let it come to room temperature before baking with it
Storage Tips for Dried Starter and Flour
How you store your ingredients has a huge impact on how long they last. Here are some simple best practices.
Keep it airtight
Once opened, transfer dried starter flakes and flour into sealed containers or ziplock bags with the air pressed out. This prevents moisture from getting in and keeps bugs out.
Store in a cool, dry place
Heat, light and humidity are the enemies of sourdough ingredients. Store them in a pantry or deep cupboard, away from stovetops or ovens, and in a container that blocks out light.
Label your bags or containers
It’s easy to forget when you bought something. A quick label with the date helps you keep track and rotate older ingredients first.
Final Thoughts
Whether you’re activating your starter tomorrow or saving it for a later date, dried starter flakes and bread flour are designed to be flexible.
Just store them well. Keep them cool, dry and airtight, and they’ll be ready when you are. And if you’re ever unsure, send us a photo or reach out. We’re here to help you revive your starter and get back into baking.
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