November 26, 2009 - 6:34am
Too much pre-ferment?
I've been having great success using a 100% poolish fermented for 16-18 hours prior to final mixing. However my loaves leave a little to be desired in terms of final rise and volume. It occurred to me this morning (too late to do anything about it for today's batch) that perhaps too large a percentage of my flour was prefermented. A little quick math tells me that the prefermented portion represents 55-60% of the total flour. The yeast may just be running out of raw flour before they have a chance to lift the final rise. Am I on the right track?
Share
There are formulas that call for even higher percentages, but a more typical amount of pre-ferment would be in the 20-30% range.
A couple of possibilities come to mind. First, you could simply reduce the amount of pre-ferment and increase the amount of flour in the final dough to arrive at the desired dough weight. Or, you could treat the poolish as if it were the bulk ferment, mix in the final dough ingredients, do a rest to allow the flour to completely hydrate, then proceed to shaping and final fermentation. Note that I'm assuming you do a bulk ferment after mixing the final dough, prior to shaping and final ferment.
Maybe one of those will work, maybe you will come up with something better.
Paul
I'm currently making a bread that has 95% preferment, 4th time in 7 days. The bread comes out just fine. I agree with Paul it is way more common for me to make bread with preferments in the range of 20%-30%.
Are you sure you aren't making a too long preferment? I mean, are you sure you are mixing in the other ingredients only when the preferment is at the top of its height and not already collapsed?
I do an autolyse rest after mixing the final dough, bulk ferment through a couple folds (usually about 90 min total), preshape, final shape, bake. The dough rises just fine during the bulk ferment but just seems to run out of steam duing the final rise. The preferment is definitely going strong when I mix. By the final mix it will have been degassed and doubled twice, mixed at the top of the second doubling. I simply worried that I wasn't giving it enough raw flour to support strong fermentation through the final rise.
BTW, my final doughs are unenriched, 60-65%, 2% salt, 1.8% yeast. Flavor-wise this formula has been a big hit, I'm just looking for juse a little more volume.
EDIT: Just to be absolutely clear I'm not making naturally leavened bread yet. I make the poolish purely for flavor and texture. The final dough mix includes a normal complement of commercial yeast.
That's a really high percentage of preferment, and chances are good that the yeast is running out of food. I would think that you'd notice that the rise during bulk fermentation is too quick - that would certainly be a sign. And with that much preferment, if you're doing a fold, you may end up expending the yeast's power to rise the dough again.
Twenty to thirty percent preferment is much more common. Also, while I do an 18 hr. poolish at work, I realize that I'm really pushing the envelope as far as its development is concerned. I don't know what the temperature is where you're doing your preferment, but you might also consider either finding a cooler place or reducing the amount of yeast added so you're catching the preferment at its peak and not after. That will definitely affect the dough's rising power once mixed.
But bottom line: fifty percent preferment is probably way too high for that fermentation time.
Larry
I just added it above, but I'm not seeking leavening power from the poolish, so I don't sweat too much about catching it at the top of the rise. I give it a long ripening time simply to ensure full fermentation. I try to time it as close as I can but I err on the side of it being done earlier than needed.
The justly famous "no knead" bread recipe from Jim Lahey of Sullivan Street Bakery, originally published Nov 2006 in the New York Times, is 100% prefermented dough.
Therefore it would seem one can make an excellent loaf of bread with 100% prefermented dough.
========
For the original recipe for no-knead bread as published in the NYT, see ...
New York Times No-knead Bread
You are indeed pre-fermenting a very high percentage of the flour. I have seen a formula that pre-ferments 43% of the flour and the baker chose to add 0.25% of diastatic malt powder into the final mix to balance this out.
You may wish to try this if you want to continue to pre-ferment such a high percentage of your flour.
Hope this helps.