Rise, Sir Yeast of Amateurhackbread

February 10, 2010 9:59 AM

Can I keep a batch of poolish in the fridge for a few days, or do I start over?

I put together a batch of poolish yesterday and then put it in the fridge before I left for work. Now my work schedule has changed, and I won't be able to get back to work on the bread until Saturday. Will the poolish still be useful if it stays in the fridge, or should I ditch it and start a new batch on Friday?

(Any other bread baking tips appreciated. Thanks!)

posted by azpenguin to food & drink (9 answers total)

It'll be fine. You're going for a sour taste, right? Today being Wednesday, it should be okay by Saturday. Watch the bubbles. If tomorrow evening it looks like fewer bubbles are forming, it might be starting to die. If so, remove half of the starter, and then replace with an equal amount of flour/water. Mix well. I'd let it sit overnight at room temp, and then put back into the fridge on Friday.

You can also just leave it at room temp the whole time and feed it every day (by removing half and replacing with flour/water as above). As long as the yeasties have fresh food, they'll keep themselves alive.
posted by mudpuppie at 10:10 AM on February 10, 2010

Flour and water are cheap, so if your unsure and need the bread, it might be prudent to start over.

That said, it depends on if it's been active or dormant in the fridge. Has it risen, are there lots of bubbles? If so, it may not make it until then.

If not, I'd pull it out on Friday, give it a stir, and run with it. IMO, it should be good.
posted by -t at 10:14 AM on February 10, 2010

Poolish? Ahh, you mean starter, as in sourdough. Never heard that other term, until now.
posted by Rash at 10:23 AM on February 10, 2010

Not so much a starter in the sense of a sourdough starter. It's a pre-ferment for rustic-type bread; it's usually done a day before and that's it.
posted by azpenguin at 10:29 AM on February 10, 2010 [1 favorite]

-t is the bread baker in our house, but I tend to think of poolish as being more for flavor than for leavening; if it still tastes good on Friday I'd go with it, maybe upping the yeast in the dough mix if it's gone a bit flat?

You could always start another batch on Friday and make a double batch of bread on Saturday to compare the taste.
posted by peachfuzz at 10:32 AM on February 10, 2010

The man I view as the final authority on these things, Peter Reinhart, says it's fine in the fridge for 3 days and it can be frozen for up to 3 months in an airtight plastic bag. I myself have done extensive, completely accidental research on the delayed use of pre-ferments. I've found that it won't kill you if you keep it longer than 3 days, but it might start to develop some sour, fermenty off-flavors.
posted by ourobouros at 1:22 PM on February 10, 2010

Rash, you can find a full explanation of poolish, biga, and other pre-ferments here. And in case it isn't clear to everyone by now, I absolutely love The Bread-Baker's Apprentice and highly recommend it for anyone who wants to up their bread-baking game.
posted by ourobouros at 1:29 PM on February 10, 2010 [2 favorites]

I would refrigerate it a few hours before you would have used it, since it will to continue to ferment in the refrigerator (albeit at a much slower rate). The poolish will contribute some structure to the finished loaf, so if it's overfermented your loaf might come out flatter as well as more sour.

You also don't need to wait for the poolish to come back up to room temperature before mixing your final dough. If you do, it will most definitely overferment. But you do need to compensate with warmer water to get your desired dough temperature.

The formula I use for desired dough temperature comes from Peter Hamelman's book Bread. It isn't perfect , but it gives you at least a framework for approaching the problem.

Take your desired dough temperature and multiply it times 4. If you're not using a preferment multiply it times 3. Subtract from this the temperatures of the room, the flour, and the preferment. Then subtract the "friction factor" which acconuts for the heat added by the friction of the mixing process. If your mixing by hand this number is usually very low. I use 10 or 20 (F). The desired water temperature is whatever's left. (After a few iterations you can refine the friction factor number to account for the particular dough you're making and the particular mixer you're using.)

An example:
You desire a dough temperature of 75 (F). Your kitchen is 77, your flour is 78, your preferment is 40. You are mixing by hand, so your friction factor, we will guess, is 10.
75 (desired dough temp) x 4 = 300
300 - 77 (the room) = 223
223 - 78 (the flour) = 145
145 - 40 (the preferment) = 105
105 - 10 (friction factor) = 95
For a final dough temperature of 75 degrees you should use 95 degree water.

Or, you could just use "warm" water. Bread is kind of like that, mostly
posted by clockwork at 10:40 AM on February 11, 2010

Update - I went ahead and ran with what I had. The bread came out pretty nicely; I could have done better but I missed a temperature change (I mixed up the 5 minute and 10 minutes that I was reading so the bread was at 500 degrees for five minutes too long. However, it's tasty, and my wife, who isn't a homemade bread fan, liked it. I'm going to get a copy of the book above; it looks like a great resource. Thanks, all!
posted by azpenguin at 9:51 AM on February 15, 2010