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Other than Brewing => All Things Food => Topic started by: tygo on November 21, 2010, 04:40:45 AM

Title: Bread Pre-ferments
Post by: tygo on November 21, 2010, 04:40:45 AM
So I did a 2 hour pre-ferment earlier today and I've got an overnight one going right now but here's my question:

What is the yeast fermenting?  Standard pre-ferment recipes call for flour, water, and yeast.  Does bread yeast have the ability to convert flour starch?

The bread from the earlier batch turned out great.  Served it with some red wine Italian sausage soup.
Title: Re: Bread Pre-ferments
Post by: The Professor on November 21, 2010, 04:45:40 AM
The flour you buy in the supermarket, whether it's 'all purpose'  or 'bread' flour, has some malted barley flour blended into it.   
That's what the yeasties feast upon.
Title: Re: Bread Pre-ferments
Post by: tygo on November 21, 2010, 04:55:49 AM
Well, that makes a bit of sense I guess, but it's still starch right?  I can't imagine that the 110F water I'm adding is allowing for enzymatic conversion of that malt flour to sugars.   
Title: Re: Bread Pre-ferments
Post by: Tim McManus on November 21, 2010, 06:10:33 AM
Flour is technically a sugar per se.  Yeast can consume a carbohydrate chain of four sugars or less.  You're not trying to ferment the entire loaf, but there's enough residual sugars in the flour for the yeast to feed on.
Title: Re: Bread Pre-ferments
Post by: MrNate on November 21, 2010, 06:22:22 AM
Dumb question time - What's a pre-ferment?
Title: Re: Bread Pre-ferments
Post by: alemental on November 21, 2010, 11:03:13 AM
Well, that makes a bit of sense I guess, but it's still starch right?  I can't imagine that the 110F water I'm adding is allowing for enzymatic conversion of that malt flour to sugars.   


Unless you are keeping your dough at a high temperature, the enzymes will survive & continue to break down the complex carbohydrates into simpler ones, which leads eventually to sugars. The Professor is correct about the added malt in flour, but you can take wheat berries & grind them into flour, and it will still benefit from a preferment.
Title: Re: Bread Pre-ferments
Post by: alemental on November 21, 2010, 11:10:42 AM
Dumb question time - What's a pre-ferment?

Not a dumb question at all. A preferment is taking some of the flour from a batch of dough, usually a lot of the water, and just a little of the yeast or sourdough culture and letting it start fermenting well before the rest of the ingredients are added to finish fermenting the dough. This breaks down some of the complex carbohydrates into  simpler ones, including sugars, that make for better flavor. Just adding sugar to the dough without prefermentation will not give you the same results.
Title: Re: Bread Pre-ferments
Post by: tschmidlin on November 22, 2010, 10:58:14 AM
Well, that makes a bit of sense I guess, but it's still starch right?  I can't imagine that the 110F water I'm adding is allowing for enzymatic conversion of that malt flour to sugars.   
Sure it can be . . . the amylase in your saliva works at 98.6F . . . just because it's not the optimal temperature doesn't mean it's not doing anything. ;)
Title: Re: Bread Pre-ferments
Post by: beerocd on November 22, 2010, 12:56:09 PM
Just adding sugar to the dough without prefermentation will not give you the same results.

Depends, right? On what you're making. I like the No Knead Bread (http://www.nytimes.com/2006/11/08/dining/081mrex.html); that's just one giant pre-ferment based on what I'm reading here.

Title: Re: Bread Pre-ferments
Post by: alemental on November 22, 2010, 06:03:29 PM
Yep, you got it.
It is just like a big preferment. Note how little yeast is required for the no knead breads; that's why it can ferment for 18 hours without ruining the dough. All that time lets the enzymes take care of business and develop that refined flavor. The yeast or sourdough then has plenty of time to grow into what is essentially a large enough pitch, so to speak.
That it is also about the easiest way to make bread is a bonus.
Title: Re: Bread Pre-ferments
Post by: euge on November 22, 2010, 06:58:20 PM
I've always called it a poolish. And IMO the approach lends itself to making great bread.

Title: Re: Bread Pre-ferments
Post by: MrNate on November 22, 2010, 08:22:27 PM
That's what I was thinking too, but it sounds like maybe this is something different?

Eh, whatever. I hope never to become an expert baker like I hope never to become an expert brewer. Too much stuff to learn.
Title: Re: Bread Pre-ferments
Post by: alemental on November 22, 2010, 10:55:54 PM
I've always called it a poolish. And IMO the approach lends itself to making great bread.



If it's 100% hydration - that is, the water weight equals the flour weight - it is indeed a poolish. If it is significantly drier, it is called a biga. And you are exactly right; preferments ARE just what can make an ordinary bread into great bread. One with depth of flavor.
Title: Re: Bread Pre-ferments
Post by: tygo on November 23, 2010, 02:34:29 AM
I did a poolish for the one I made on Sunday.  The flavor ended up really nice.
Title: Re: Bread Pre-ferments
Post by: tygo on November 24, 2010, 03:51:25 AM
I baked up two loaves this last weekend, the first with a two hour pre-ferment at 200% hydration and the second the overnight poolish.  Last night I sampled what was left of both loaves and not only did the poolish loaf have more depth of flavor but the crumb was much more desirable.  The first loaf, although good, was somewhat dense compared to the second one which had a nice balance of "big holes" and "small holes".