Dough Handling?
The photo's below are from a recent bake, but I've seen the same phenomena on multiple previous bakes. The first photo shows the bread's crumb at the very center of the boule. One can see it's relatively closed. The second photo shows the crumb nearer the edge of the same loaf. The crumb appears much more open, to me. I'm not certain the photos illustrate it as much as my eye perceives the difference.
I think the difference is attributible to the way I preshape, and shape the boules, but I'm not certain. I shape boules following the instructions I've learned from watching multiple videos, and recently at KA Baking Center. On every boule I recall shaping the center of the loaves have been more closed than the periphery. Any comments re alternative causes, and, more importantly, how I might achieve a more homogeneous crumb will be appreciated.
Thanks, in advance.
David G.
And I have a unproven notion about why. In the first few minutes of the bake, the crust hasn't yet dried and hardened. At the same time, heat is beginning to penetrate the outermost layer of dough, triggering a lot of activity by the yeast. That, in turn, leads to more gas production, which inflates the existing bubbles in the dough, contributing to the loaf's oven-spring.
As the bake proceeds, the crust dries and hardens, preventing any further outward expansion. The temperature in the outer section of the loaf rises past the temperature where the yeast in that zone are killed, stopping any further growth there. Meanwhile, the heat penetrates to the center portion of the loaf, which encourages accelerated growth of the yeast there. However, with the crust having hardened and the outer portion of the crumb growing ever firmer, there's no possibility of expansion. Hence, a tighter crumb at the center of the loaf.
Is that what really happens? I don't know for sure. Seems like a possibility, though.
Paul
Oddly, after I posted this query, I thought of your hypothesis, but didn't think about the suftace drying as well. Like you, I haven't the slightest idea how to prove this. Perfhaps a more efficient steam delivery, and maintenance would partially solve the problem. I don't like using a makeshift cloche (sp?). I've tried upside-down bowls, and foil pans. Burnt myself twice, even though I wear long oven mittens--always been a bit of a klutz.
I was especially careful handling the dough gently when I shaped these loaves, but still saw this effect. It does vary, loaf to loaf.
I'll keep experimenting.
Thanks,
David G
this intrigues me, as I also have noticed this happening in several of my bakes! i somewhat had tossed the idea of shaping being the issue, as I think i tend to shape my edges more firmly than the centers, so if shaping was the problem, it should have been denser on the edge? interesting hypothesis...
Good to know that I'm not the only one experiencing this.