What happens to the bread when you make it?

What's in bread?

Let's start with the basics, for classic bread, which is improperly called "white bread", baguette for example, it's extremely simple there can/should only be 4 things: flour, water, a bit of salt, and a dollop of yeast or leaven, or sometimes both. Full stop!

All the rest: additives, improvers, flavour enhancers, correctors, etc. are chemicals, "crutches" as the bakers say, additions that are only there for bad bakers or the food industry, or both, and that have no place in a good quality bread.

I'll detail a bit: Flour contains mainly starch (a sugar), a lot, and gluten (a protein), quite a bit.

What happens?

As soon as the baker mixes the water, flour, and yeast/leaven, it starts, a complex mechanism gets underway, which will result in the little daily miracle of crusty bread.

1) On the first hand, the yeast or sourdough, microscopic fungi, will attack the starch, and produce carbon dioxide, CO₂ and alcohol.
This is the so-called alcoholic fermentation, the same as in wine and beer, but don't worry about the alcohol, it will disappear when cooked (at 250°C).

2) On the other hand, kneading the future dough acts mechanically on its gluten, little by little this protein structures itself into a network, and thus forms a rather elastic dough, which is at the same time capable of retaining the CO₂ produced by the fermentation.

It is this CO₂, trapped by the network, which cannot escape and which forms bubbles in the dough, bubbles which will become cells in the bread once it is baked.
The dough is said to be structured or "networked" when the kneading is finished, a moment not so easy to determine.

You see it's a duo of action, one without the other, would not give good bread :

- No fermentation => no CO₂ => flat, hard dough => inedible bread.
- No gluten network => the CO₂ from the fermentation escapes because it is not retained => flat and hard dough => bread that is also inedible.

The dough, well kneaded and leavened, is put in the oven, at around 250°C, the alcohol is quickly eliminated, the cooking at the beginning accelerates a little the production of CO₂ from the yeast, the dough still rises, then the cooking really starts and freezes everything.
The bubbles are cooked, the crumb is aerated, and the crust turns golden under the action of the famous Maillard reactions.
And in the end, a crisp, golden bread with a delicious smell spreads all around the oven.

Is that all?

Well in broad strokes yes, overall it's all there, but it's the whole difficulty of the baking trade to manage these 2 aspects of fermentation and kneading, then baking, to make you, regularly, a good loaf.

Some points of detail

- The gluten network, this is what makes a gluten-free bread very difficult to make, it's not really bread some would say, it's impossible others would say, because you have to manage to imitate a network to trap the CO₂, either by adding a binder (bof!) or by moulding the dough, a bit like a cake, or both. This is why gluten-free breads look more like cakes than breads.

It should also be noted that the gluten of today is very different from that of just 50 years ago, the original sin coming from the 70's when we started to make bread, faster and faster, whiter and whiter and more and more bland, and therefore increased the gluten content of the flours, and also selected short-legged wheats, richer and richer in an increasingly strong gluten. This is undoubtedly the main cause of the many gluten-related problems of our time, a gluten that is much less digestible than before.

One last piece of information about gluten, sourdough breads, apart from their extraordinary taste and nutritional advantages, and partly thanks to their long, even very long, fermentation times, these sourdough breads therefore favour the digestibility of gluten.
In other words, if you have problems with gluten in your daily diet, try (quality) sourdough bread.

- The fermentation-kneading duo does not only apply to bread, but also to viennoiserie (brioche, croissants,...) to pizzas, and in fact to all the so-called "fermented" doughs precisely, it's the borderline between baking and pastry-making.

Respectus panis

If you don't knead the dough, no gluten network you will have understood, but there is another alternative which is time: If you only mix the ingredients, 1 or 2 minutes maximum, and leave the dough for a very long time (18 to 20 hours) at around 16°C with very little yeast/leaven and less salt, the network will still build up by itself, very slowly, but surely. "Time is on my side", if you have the Stones ref...

This method called "Respectus panis", a long acronym, is in the making among good bakers, this long rest is also the assurance of very developed tastes in the bread thus treated, which is just excellent, and which also seems to be better tolerated by those who have problems with gluten. But here's the thing, it takes time, a lot of time, and a certain amount of baking mastery to make this kind of bread work.


In summary: Bread is a duo of actions, kneading (1) to form the gluten network, which will trap the CO₂ from fermentation (2).