If you’ve tried recipes like my No-Knead Artisan-Style Sourdough Bread, then you may have stumbled across the float test.
Many sourdough recipes rely on the float test to determine whether a starter is ready to bake. If your starter doesn’t pass this test, you may need to wait a few hours (or several days) before you can try again.
But is the float test helpful? Is it a good way to ensure your bread will rise as it should? Let’s take a closer look at this common baking tip.
What Is the Float Test?
As sourdough starter matures, it releases small carbon dioxide bubbles. These bubbles often become trapped within the gluten network of the flour and water mixture. The longer your starter rises, the more gas becomes trapped in the mixture.
The float test is a technique to see whether the starter has trapped enough gas to adequately lift your bread dough.
To perform the float test, simply spoon some of your starter into a cup of water. If the blob sinks straight to the bottom, the starter has not developed enough to adequately trap carbon dioxide. If it floats on the surface of the water, your dough has enough carbon dioxide to lift your bread.
In theory, anyway.
Why Isn’t It Reliable?
The float test works well enough for some recipes, but it does have its drawbacks. The float test isn’t reliable in a few different situations, and if you rely too heavily on it to determine whether you should bake, you might end up with a flat loaf.
False Positives
A false positive happens when a starter traps enough carbon dioxide to float. However, it doesn’t necessarily mean you should put it in your bread just yet.
Some flours, such as whole meal and rye, hold onto gas better than others. A rye starter may be more likely to float than an all-purpose one.
Additionally, not all starters are fed to 100% hydration. A stiffer starter, for example, can hold more gas than a liquid one, resulting in a false positive.
False Negatives
A false negative occurs when a fully mature starter sinks to the bottom, giving the impression that it’s not ready to bake. However, if you were to put it in your bread, you may still see a beautiful rise and oven spring.
High hydration, or liquid, starters have more water than flour. When dropped in even more water, the starter immediately starts to break down, resulting in a sinking negative.
Additionally, sourdough starters are delicate. If you are rough when handling your starter and dropping it into the water, you may knock out the gas that would otherwise make your starter float.
What Should You Do Instead?
Knowing when your starter is ready to bake is an art, which is why many bakers recommend using the float test. It’s fast and easy to understand.
But because the float test is inconsistent, you may want to try the following methods instead:
- Look for Bubbles and Foam: When you first make a sourdough starter, the starter will look flat and smooth with the occasional bubble on its surface. But as your starter matures, it will have more bubbles on its surface. A few hours after a feeding, an active starter will foam noticeably.
- Measure the Rise and Fall: Active sourdough starters will rise and fall predictably, often doubling in size a few hours after a feeding. If you keep your starter in a jar, you can place a rubber band around the jar to mark the starter level. When the starter doubles above the rubber band mark, it’s almost ready to bake. Most recipes work best when your starter is just beginning to sag under its own weight.
- Keep Track of Its Age: How old is your sourdough starter? Most week-old sourdough starters aren’t strong enough for artisan-style loaves, though you can definitely use them to make sandwich loaves. If you want to use your starter for more complicated breads, make sure your starter is at least 2 weeks old, preferably 4 weeks or more.
You should note that all of these methods depend on you regularly feeding your sourdough starter. If your feeding times vary or if you feed your starter inconsistently, you may struggle to predict your starter’s peak baking times. If you recently took your starter out of the fridge, you’ll need to give it at least three days of regular feedings before it’s ready to use again.
Want to Know More?
I understand that sourdough starters can be fickle to work with. I’ve covered a lot of common sourdough starter questions in the past, but if you have additional questions, I’d be happy to answer them. Just post them in the comments section below and I’ll get back with you.
FAQs
The float test works well enough for some recipes, but it does have its drawbacks. The float test isn't reliable in a few different situations, and if you rely too heavily on it to determine whether you should bake, you might end up with a flat loaf.
Why is my dough not passing the float test? ›
When the Float Test May Fail. Several factors contribute to the float test not being the most dependable. A new starter: A young starter hasn't yet developed the strength needed to rise your bread dough. Keep track of its age, continue a consistent feeding schedule, and keep it in a warm spot to encourage activity.
Why won't my sourdough starter pass the float test? ›
It probably just needs feeding again. The starter is usually baking ready a few hours after being fed. So you could simply try discarding a tiny bit of the starter, add another 60g of lukewarm water and 60g of flour, and try again in a couple of hours (or tomorrow).
What if my leaven doesn't float? ›
This doesn't mean that it will not allow your bread dough to rise once it's ready to bake with. If your sourdough starter won't float, it may well be due to the type of flour you are using. You can read more about the best flour for sourdough bread here.
What if my starter isn't doubling? ›
“My starter was doubling consistently and now it's not, what do I do?” This happens to us all at some point, your starter just seems less active than it was before or isn't rising anymore. Try giving your starter a feeding of whole wheat flour, the extra protein content in the flour will give your starter a boost.
What to do if dough doesn t pass window test? ›
It's called the windowpane test because you should be able to see light through it, just like you can see sunlight through a windowpane! If the pizza dough tears easily, it is not ready for proofing and needs more kneading. Continue to knead pizza dough for a few more minutes, then do the window test again.
Why is my dough so dense and not rising? ›
Your rise is too short or too long. If too short, the yeast won't have a chance to create bubbles and CO2 to make the bubbles expand. If too long, the dough will collapse onto itself. The temperature during rise is too hot or too cold.
What happens if sourdough starter isn't bubbling? ›
Some sourdough starters double within 24 hours, others take a few weeks of feeding and coaxing. The truth is, if your starter is bubbling, then it's showing that there is signs of fermentation. If it's not doubling (or even tripling) then it's not ready to bake sourdough with. Give it more time to develop and mature.
Why is my sourdough starter hooch but not rising? ›
My sourdough starter has hooch but not rising? If your sourdough starter has hooch, this indicates that it is hungry so it will not rise. A sourdough starter rises as it consumes food and the yeast produce CO2 gas, causing the mixture to rise in the jar. You'll be able to see bubbles forming on the surface of the jar.
What if my sourdough starter is ready but I am not overnight? ›
If things get delayed, I would pop the starter in the fridge and use it later in the day, without an additional feed. If I want to prep the dough in the afternoon/evening and proof overnight in the fridge, then I would feed the starter in the morning.
stir your starter in between feedings - try stirring it twice in between feedings and really give it a chance to get oxygen into the mix. This will help to activate your starter without too much effort.
Does levain need to pass the float test? ›
The float test: Take a small spoonful of levain. Place it in a glass of room temperature water. If it floats, it's ready. If it doesn't float, it may need more time OR you missed the peak.
How long after feeding starter can I use it? ›
*Do not try baking with your starter right after feeding it. Allow time for it to grow and feast on the flour before using it. Starters are usually ready to bake with around 4-12 hours after a feeding depending on the amount you feed your starter. The larger the feeding, the more time it needs to ferment.
Can I use my starter if it doesn't float? ›
Many sourdough recipes rely on the float test to determine whether a starter is ready to bake. If your starter doesn't pass this test, you may need to wait a few hours (or several days) before you can try again.
Why is my sourdough starter taking 12 hours to rise? ›
Most commonly, the issue here has to do with temperature (which is very important). If your sourdough starter is kept at a low temp, even 70°F (21°C), it will slow fermentation activity and appear to be sluggish, taking longer to rise and progress through the typical signs of fermentation. The solution: keep it warm.
Can I feed my starter without discarding? ›
How to increase a starter. If your recipe calls for more than 227g (about 1 cup) of starter, feed it without discarding until you've reached the amount you need (plus 113g to keep and feed again).
Why is my dough not proving? ›
Yeast is too hot Yeast may have been dissolved in water that was too hot, or the liquid ingredients in the recipe may be too hot, causing the yeast to die. Yeast needs to be warm - not too hot, not too cold. Yeast is too cold If the other ingredients are too cold, it could cause some of the yeast to die.
Why can't i score my dough? ›
It is difficult to score very soft dough or dough at room temperature. Make sure your blade is as sharp as possible and try one very quick stroke. Sometimes this is just not possible.
What causes a weak dough? ›
Your dough can become sticky when you add too much water or the flour isn't suitable for the type of dough you are making. Over proofing or fermenting the dough can also result in the gluten structure weakening causing sticky dough.
