“Punching down” dough doesn’t literally mean that you do a Muhammad Ali impression. It is more accurately described as “degassing”. The goal is to let out some of the carbon dioxide that the yeast have been producing, allowing them to continue the fermentation process without turning your dough into a big stretchy mass that is too floppy to hold its shape. The other goal of degassing is to move the dough around a little bit so as to bring the yeast into contact with parts of the dough they haven’t already chewed their way through.
The simplest “punch down” is to gently press your fist into the center of the dough a few times until it has substantially deflated. Another method, which moves the dough around a bit more, involves folding the “corners” of the dough back in to the center. I say “corners” because a round dough ball doesn’t have corners per se, but you can probably picture what I mean. Imagine that it did have four corners and, one by one, grab them and fold them back over the center of the dough. The most aggressive form of degassing is to turn the dough out of whatever container it’s fermenting in and literally knead it a few times until it is totally degassed.
How aggressive a form of degassing you use depends a lot on the final structure of the bread that you’re going for. If you want a tight, even-crumbed sandwich loaf, a full degassing is probably appropriate. If you want an artisan loaf with lots of big pockets, a gentle punch-down is more appropriate. Of course, there are other factors that will influence the final structure of your bread, but you’ll never get nice, holey artisan bread if you fully degas your dough.
As I said in my previous post on this topic, and I will continue to reiterate, you don’t need to stress too much about this, because at the end of the day, what comes out of your oven will probably be delicious bread. It might not be the exact type of delicious bread you were hoping for, but people’s eyes will still roll back in their head when they taste it, and only you will know it’s any different than you planned. If you are entering your bread into a competition, then perhaps the exact nature of the crumb will matter, but by that point, you’ll be well past worrying about my little tips.
One thing you must keep in mind, however, is that the dough must be allowed to rise between the final degassing and the baking. The exact number of rises varies, but typically the dough will be allowed to rise in a big mass, punched down, allowed to rise again, and that process may occur for a total of one to three degassings. After the final degassing, the dough is typically divided into smaller pieces and shaped into whatever form it will have for baking. Then it is given a final rise and it is baked. this final rise is critically important because the handling that occurs during shaping will degas the dough some, and if you bake a degassed dough, you get something dense like a pretzel. Not delicious, unless you’re working with a pretzel recipe!
