sourdough starter... freezing flour
Can freezing flour (which I do to prevent weevils) also kill good enzymes or bacteria or whatever it is needed for a natural sourdough starter? Here's my problem:
I'm trying to do a starter. Everything was working great until I fed it one day with a batch of flour that had been previously in the freezer. From there, the thing was just dead. Completely. No movement or anything. Prior to that (for about 2-3 days - its a new starter) everything was going great - was raising about 2+ times its size, was bubbling, etc. But I was using flour that wasn't ever frozen.
The new flour was recently purchased, and was King Arthur Bread Flour. Shouldn't have been a problem.
(oh, when I used the frozen flour, I made sure the temp had come back up to room temp before feeding)
What other explanation could there be for a sudden death of a starter? I made sure everything that touched it was clean... can't figure out what I'm doing wrong here...
Please help... I've been dying to try some of the breads in Nancy Silverton's La Brea Bakery book, as well as in Beranbaum's Bread Bible. I can't wait much longer!
Are you sure it's dead? I've had a starter for more than a year (given to me by a friend) - every time I use it and refresh it, it bubbles and expands. It then just subsides and stops doing anything at all. I put it in the fridge, until I need it next (although I will refresh it if it sits for more than a few weeks). I know that it's working, because a) the bread is most certainly sour, and b) it bubbles again at the next refresh. I am most certainly not an expert baker - but I have spoken to my friend who knows a lot more, and he says that I should just keep it going until it turns liquidy and purple. He's done this for several years at a shot.
I really, really enjoy bread made with this starter - I've experimented with rye and various whole wheats. It's too bad that bread is off my list (diabetic) and that my family doesn't enjoy it as much as I do - I'd never need to refresh the starter (other than using it). So I have a hot slice with butter once a month or so...
My understanding is that the yeast and bacteria metabolise the starch/sugars in the flour; the bacteria produce glucose to feed the yeast, and acid to help protect it; and dead yeast provide amino acids and fatty acids to the lactobacilli. Sometimes enhancers, such as oxidants (which facilitate gluten formation and bleach out the natural pigments) or proteins are added to flours, but these aren't for the sake of helping the starter. I don't think there is anything in the flour that the starter would need that could be destroyed by freezing.
I've had limited experience with this (have kept a starter for just 8 months), so can't diagnose, but here are a few other reasons I can think of that might kill one:
1. It was exposed to high temperatures (>100F)
2. It starved
3. It was weak and fed at a frequency faster than it could grow
4. It was taken over by unfriendly microoganisms
Also some people say prolonged exposure to metal can hurt the starter, but dunno if this could actually kill it.
As applehome pointed out, some dead looking starters are actually still barely alive. If that's the case it may take several rounds of 12 hour feedings to get it going again.
You might be able to get more info from the folks on the rec.food.sourdough newsgroup.
thank you for your thoughtful reply.
regarding your thoughts of possible reasons my starter quickly died (or went into extreme hibernation). I'm not sure. I know it wasn't exposed to extreme heat. I fed it with room-temperature water and flour, and it isn't near anything that has been outside around 75 degrees.
I know I didn't starve it... since it was only 4 days old to begin with (remember, I'm just getting started with this starter), and fed it just the other day.
The third possibility, that it was weak and I fed it too quickly, is a bit more of a possibility. Though, the day before the sucker raised from about one cup to three cups in volume. Seems that it has some gusto to it.
The last, that it was overtaken by evil starter-killing microorganisms is probably the most likely. Who knows.
Anyhow, after it decided to do nothing after I fed it, I let it sit another day as is, then stirred it up, poured out half and fed it like usual. I'm noticing a few bubbles going on... so I think I may have some life in it yet. Should I try and feed it daily? or give it 48 hours to try and build some strength?
Most importantly, thanks for the rec to the sourdough usenet group. Had no idea that existed. It's great. I've been reading along in it and it is great. Thank you.
Much appreciated - Adam
I'm glad to hear that you are seeing bubbles. I don't know how much you are feeding it vs. its volume. It sounds like you are diluting, which you should and which reminds me of another reason the activity may have quieted down:
The lactobacilli produce lactic acid (around room temperature and higher) and acetic acids (around room temperature). The acids (especially the acetic) inhibits the yeast.
By using a lot of fresh flour and water for a smaller amount of starter, you dilute the acid, which makes the yeast happy. This of course needs to be balanced with the effect I mentioned earlier, that you can overdilute a weak starter. It sounds though like overdilution wasn't your problem.
But whatever you are doing, it looks like it's helping and if it were me I'd continue with that.
When I make (non-sourdough) bread, I always add a teaspoon or so of sugar to the yeast as it's proofing -- just like in people, yeast digests sugar a lot faster than flour. Might give it a little kickstart.