Yes, you generally need to discard sourdough starter when feeding, but the frequency (every 12 or 24 hours) depends on if it's at room temperature (more often) or in the fridge (less often), and 12-hour feedings are common for active, room-temp starters to prevent it from getting too big and acidic, though you can use the discard in recipes. The key isn't a strict 12-hour rule but feeding it enough to keep the microbes healthy without letting it grow unmanageably large, which requires discarding excess.
Room-temperature starter should be fed every 12 hours (twice a day) using the standard maintenance feeding procedure: discard all but 113g, and feed that 113g starter with 113g each water and flour.
Don't worry. Sourdough starters are actually pretty robust. If you don't feed your starter the yeast and bacteria in the starter will run out of food, but they'll stay alive (dormant) for a while (how long specifically depends).
If you leave sourdough on the counter longer than 3--5 hours, it may overproof, the gluten can weaken and the bread may turn more sour. It's sometimes fine in cool weather (20-22 °C) or with whole-wheat flour, but in hot weather it's risky.
Control growth: If you don't discard, your starter will grow out control and you'll have too much- you'll never use it. Reduce waste: Avoids having too much starter that you can't use. Maintain health: Keeps your starter strong and active for better bread rise.
The biggest mistake with a sourdough starter is impatience, primarily by using it before it's strong enough (weak starter) or discarding too much/feeding inefficiently, which weakens it further, leading to flat bread; you must give a new starter weeks to mature and consistently feed it at its peak for proper leavening power. Other common errors include using chlorinated water, incorrect water temperature, or ignoring temperature for sluggish activity.
I learned one way and that's what I do. I have a discard jar in my fridge, and I continue to add to it. If it gets some hooche on top, I just pour it off and use.
Reviving a stored sourdough starter. Note the sluggish activity after just one feeding. It will take a few to get going again. Let everything sit until it looks like it needs another feeding, usually 12 to 24 hours, at warm room temperature.
The 12 hour proof is just a starting point. In reality anything from 12 hours to 48 hours in the fridge will make a great loaf of bread. This means you can bake when you're ready.
If you leave your bulk fermentation at room temperature overnight it will likely overproof. You can put your dough in the refrigerator to slow things down until morning.
An overfed starter can be too diluted and it will be very watery. Your workers are there, they are just overwhelmed with too much food and water.
The 1:1:1 method for sourdough starter is a feeding ratio using equal weights of starter, flour, and water, typically measured in grams (e.g., 50g starter + 50g flour + 50g water) to refresh it, promoting quick activity and preventing excessive sourness, ideal for regular maintenance or when needing a fast-rising starter. This low ratio means less food, so microbes consume it quickly, causing the starter to peak (double in size) faster, often within 3-4 hours at room temperature.
Sourdough discard is the portion of starter that gets removed as part of its routine maintenance. Sourdough discard is the portion of starter you don't feed during routine maintenance. You can choose to dispose of it or bake with it.
I always give mine a quick stir before taking out 80g and discarding the rest. You need to feed with flour and water preferably at a ratio of 1:1:1 where this is starter:flour:water although this ratio can be different. If you are just starting to build your starter then i would recomend this ratio.
As it gets hungry, the bubbles on top will become smaller and may look a bit frothy, while bubbles will also start appearing along the sides. Don't stir your starter, as that can be misleading; observe the bubbles forming over time to get familiar with what a healthy starter looks like.
Feed the starter every 12 hours until you see it double or triple in volume within 6 to 8 hours; this means it's ready to bake with.
I've done as long as 5 days in the fridge, but 3 days is about the practical maximum before the loaf starts deteriorating and the flavor turns from sour to bitter. Most of the sour flavor comes from the cold retarding in the fridge.
Proof on the counter at room temperature to rise your dough. It won't rise much in the fridge. The fridge time gives it the sour flavor and firms up the dough which makes it easier to score.
The biggest mistake beginners make with sourdough is impatience, specifically baking with a starter that isn't strong enough or rushing fermentation, leading to flat, dense bread; they often try to bake too soon, don't let dough proof long enough, and fail to develop dough strength or learn to "read the dough" (look/feel) rather than just the clock, plus starting with overly high hydration is a common pitfall.
Premature discarding and overfeeding will weaken your starter and elongate the process. Don't discard and re-feed a weak starter before it shows increasing bubble activity or height from the previous feeding. If you don't see more bubbles or a faster rise each day, skip a feeding, and give it more time.
Once your starter is alive and active it only needs to be fed when you want to use it. Store your starter in the fridge with a fitted lid on in between uses.
Boost Your Sourdough Starter With Oxygen
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.
Is sourdough discard gut healthy? Sourdough contains some lactic acid bacteria, which are considered probiotics and may promote a healthier gut biome.
So what is “discard?” Sourdough discard is the part of the starter you GET RID OF every time you go to feed it. If I kept my entire starter and fed it time and time again, I would end up with WAY too much starter that I would have to find a use for.