If left unfed it can start to grow mold and bacteria. At that point, a starter should be thrown out and started over. Any pink, orange, or grey color should be discarded and a brand new starter should be made. A sourdough starter does have a tangy smell to it but it should never have a foul smell.
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).
It's possible to keep the sourdough discard fresher for up to 1 week by storing it in an airtight container in the fridge.
Sourdough starter CAN die if neglected for long enough in the refrigerator, because it doesn't completely stop being active in the fridge, it just slows down considerably. My starter died after 5 months of being left in the fridge unattended. So don't leave it too long!
You can either discard this liquid (or “hooch,” as it's commonly called) or stir it back into the culture. I typically stir it all in together. This can be a sign you're not feeding your starter often enough.
If you don't discard your sourdough starter, it will grow too big and be unmanageable. Not to mention you will go through an unmentionable amount of flour.
Once the sourdough starter is established on day 8, all you have to do is just give it flour and water. You no longer need to discard half of it.
The rule of any kitchen is “When in doubt, throw it out,” but I wouldn't panic and toss your starter if you only missed 1-3 days of feeding. If it's more than 3 days AND you have a warm kitchen, you'll have to make the call based on how well you know your starter.
The oldest known sourdough starter is said to have originated from clay pots unearthed in Egypt. Seamus Blackley baked a loaf of sourdough bread using yeast harvested from 4500 year old clay pots. What is this? If you want to read more about this 4500 year old sourdough starter, go here.
How do you know if sourdough starter has spoiled or gone bad? The main indicator if a sourdough starter is still good or not is if it will still rise and fall after feeding it fresh flour and water. If it does, it's still alive!
One approach is to save up all this discard in one container in the fridge in what I like to call a sourdough starter cache. Then, use all this at once in a starter discard recipe or my sourdough waffles, pancakes, or banana bread at the end of the week.
Can I Use Sourdough Discard Straight From The Fridge? Yes you can use sourdough discard straight from the fridge, you don't need to let it come to room temperature if you don't want to.
Yes, there are actually several health benefits to using sourdough discard in your cooking and baking. Sourdough discard is rich in probiotics, which can help promote a healthy gut microbiome and improve digestion.
Feed the starter 1/2 cup (4 ounces, 113g) water and a scant 1 cup (4 ounces, 113g) all-purpose flour twice a day, discarding all but 1/2 cup (4 ounces, 113g) of the starter before each feeding. It should soon become healthy, bubbly, and active.
Generally a starter can stay at room temperature without feeding for a maximum of 3 days. After that you will need to give the starter few feedings before you can use it again. This is because it will become less strong and it will need time and food to become strong again.
Because, yes, you can overfeed your sourdough. The explanation is quite simple: if you add too much water and flour, you're basically diluting the natural population of yeast and bacteria. This means that your sourdough starter will not rise much and will not be very bubbly.
A mature sourdough starter can last for several weeks to months if kept in a refrigerator without being fed.
8. A Mature Sourdough Starter is More Sour Than a Young One. If you have made a starter from scratch, it doesn't fully mature and develop its full depth of flavor until a good few months down the line. A more mature sourdough starter will give a more sour flavor.
The very short answer is, your sourdough starter generally will be at its peak anything between 4 and 12 hours after feeding. The optimum time to use it will be when there are lots of bubbles at its surface and it has has physically risen to its peak level, just before deflating back down again.
What if I miss feeding my sourdough starter? If you miss one of your starter feedings, it'll be just fine. Give it a feeding when you next remember it needs one, and continue with your daily feedings as usual.
The overall process typically takes 7 days, if the temperature is warm enough. However, it can take up to 2 weeks or more for a strong starter to become established.
One or Two Week Break
While we normally recommend feeding a sourdough starter weekly when stored in the refrigerator, leaving it a bit longer once or twice per year will not harm the starter.
Sourdough contains a variety of vitamins and nutrients, making it super beneficial to your day-to-day health. Sourdough bread has small to moderate amounts of: iron, manganese, calcium, B1-B6, B12, folate, zinc, potassium, thiamin, niacin, riboflavin, selenium, iron, manganese, magnesium, phosphorus, and vitamin E.
About 6-8 hours after you feed your starter, it should be at its peak activity level, nearly doubled in size, bubbly, and ready to use in lots of recipes. We refer to this stage as active but it's also referred to as mature or ripe starter in other recipes.