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Original poster

To not understand sourdough starters and how the world works?

63 replies

TeaSqueezingpos · 12/03/2026 08:59

I just can’t wrap my head around the fact you can mix together a mixture of flour and tepid water, and leave it out in a lukewarm environment for up to 2 weeks, adding more flour/water and giving it a mix.. and we call it edible.

but if I left out of a mixture of anything else for 2 weeks it absolutely wouldn’t be edible would it 🤣 what makes it so different? Why is that bacteria safe but the bacteria that grows on my already baked bread.. or any other food/sauce ect not safe?! Like pancake batter.. you wouldn’t eat pancake batter that’s been left in the worktop for over a week?!

I just don’t understand and I don’t think any amount of explaining will convince my brain that it’s normal.

I want to try it, but I’m scared of killing my family with a horrendous bacterial disease in the process.

OP posts:
ConstanzeMozart · 12/03/2026 09:24

User567573 · 12/03/2026 09:11

It works because the yeast you need for baking grows much faster than harmful bacteria and mould. You are obviously not leaving it to rot for 2 weeks. The whole point of discarding and feeding every day is to maintain the yeast colony and get rid of bacteria.

Each time you remove the discard, the remaining yeast gets fresh flour and water. They can multiply and strengthen their numbers. Then with each cycle, the yeast population becomes denser and more stable. Once the starter is fully matured, it becomes harder for harmful bacteria to multiply because of some specific chemistry. But only if it's still being discarded and fed regularly. If you just leave it on the countertop for a few days then it will go bad quickly.

I often wonder how many people have inadvertently poisoned themselves by refusing to discard starter because it feels wasteful, or by trying to bake too early with the "fake bloom" when you first make one. (This is the first few days when the harmful bacteria causes the mixture to rise but it smells utterly disgusting as you would expect).

I also wonder how many people don't even know the difference between yeast, bacteria, mould and lactic acid.

Edited

I don't think I understand any of this post!
I didn't know you had to discard and feed every day. Do you mean you do that as opposed to leaving it on the countertop for a few days ie leaving it without discarding and feeding?
I didn't know about the 'fake bloom'.
I definitely don't know the difference between yeast, bacteria, mould and lactic acid.

Tiptopflipflop · 12/03/2026 09:16

I cook my sourdough at 240 degrees for 40 mins, putting it into a preheated iron pot. I'd be very impressed if any murderous bacteria survived that.

drspouse · 12/03/2026 09:16

User567573 · 12/03/2026 09:11

It works because the yeast you need for baking grows much faster than harmful bacteria and mould. You are obviously not leaving it to rot for 2 weeks. The whole point of discarding and feeding every day is to maintain the yeast colony and get rid of bacteria.

Each time you remove the discard, the remaining yeast gets fresh flour and water. They can multiply and strengthen their numbers. Then with each cycle, the yeast population becomes denser and more stable. Once the starter is fully matured, it becomes harder for harmful bacteria to multiply because of some specific chemistry. But only if it's still being discarded and fed regularly. If you just leave it on the countertop for a few days then it will go bad quickly.

I often wonder how many people have inadvertently poisoned themselves by refusing to discard starter because it feels wasteful, or by trying to bake too early with the "fake bloom" when you first make one. (This is the first few days when the harmful bacteria causes the mixture to rise but it smells utterly disgusting as you would expect).

I also wonder how many people don't even know the difference between yeast, bacteria, mould and lactic acid.

Edited

Well, the OP doesn't know about the difference between bacteria and yeast, at least! So you are right.

SoScarletItWas · 12/03/2026 09:14

Wait til you hear about cheese 🤣

52andblue · 12/03/2026 09:13

I was reading about traditional Crowdie. Oats & cold water, fermented over 3 days & use some of the 'oat milk' to start the next batch.

User567573 · 12/03/2026 09:11

It works because the yeast you need for baking grows much faster than harmful bacteria and mould. You are obviously not leaving it to rot for 2 weeks. The whole point of discarding and feeding every day is to maintain the yeast colony and get rid of bacteria.

Each time you remove the discard, the remaining yeast gets fresh flour and water. They can multiply and strengthen their numbers. Then with each cycle, the yeast population becomes denser and more stable. Once the starter is fully matured, it becomes harder for harmful bacteria to multiply because of some specific chemistry. But only if it's still being discarded and fed regularly. If you just leave it on the countertop for a few days then it will go bad quickly.

I often wonder how many people have inadvertently poisoned themselves by refusing to discard starter because it feels wasteful, or by trying to bake too early with the "fake bloom" when you first make one. (This is the first few days when the harmful bacteria causes the mixture to rise but it smells utterly disgusting as you would expect).

I also wonder how many people don't even know the difference between yeast, bacteria, mould and lactic acid.

Mmmchocolatebuttons · 12/03/2026 09:08

You do cook the sourdough for like an hour at a very high temperature so that probably helps! I wouldn't recommend eating it raw.

ShakeNCake · 12/03/2026 09:08

This is a great thread title! 🤣

Bread is one of the foods I try not to think about too much, like mushrooms and anything fermented. I have apple cider vinegar that contains a bit of 'mother' and I can't bring myself to use it. Next time I'll have to buy cider vinegar that's gone no-contact 😂

stickydough · 12/03/2026 09:07

I think a lot of food left out would be fine (plenty wouldn’t too, of course!) But there are a lot of organisms that are good for us, good for our guts. You could always start by buying a sourdough starter from a company, they’d be invested in not giving you a horrendous disease, so you might feel more confident than if you make it yourself?!

shellyleppard · 12/03/2026 09:05

I'm really tempted but I'm worried its going to keep growing and growing.... like the blob movie from the 1970's!!!! 🤣🤣

Witchesbe · 12/03/2026 09:05

And think about sauerkraut 😁

Whenindoubthugitout · 12/03/2026 09:04

but wine is also fermented grapes……
so do you drink wine?

Blackisthecolour · 12/03/2026 09:02

Well I thought I understood sourdough starters until I read your post and now I feel like you. Who was the first person who forgot their