Bread deep dive: Flour, fermentation and proofing

Hello fork musketeers!

This is part 2 of the Bread deep dive I promised earlier. If you want to skip around, here's the table of contents:

1. Basic anatomy of bread and bread making
2. Flour, fermentation and proofing
3. Fat vs. fat-free doughs
4. Designs on breads

Let's start off by looking at the flour.

It's all about dat wheat

Flour is entirely starch. While most people think flour is a non-perishable item, it originally wasn't... depending on who you ask. During the 1800s, most people would bring their wheat to the miller and grind small batches to use over the summer; they'd be able to make bigger batches just before the winter. What made flour so perishable? The answer is in the grain.

The flour richer people used was different from the flour the poorer people used. It was believed foods that were more white - "purer" in a way - was healthier. So when flour is made, the grain is ground as a mix of endosperm (the actual grain); the bran and the germ; aka whole wheat flour. The flour used by wealthier folks removed the germ and the bran; whereas the flour used by the poorer folks used more germ and bran. Germ and bran have more oils and nutrients in it, thus they would expire more quickly than their germ/bran-free cousin.

As it turns out, flour made exclusively with the endosperm didn't contain enough nutrients. In Canada, flour is mandated to always mix the endosperm and some germ in it; the bran is usually removed - to be used as livestock feed - or kept in. That being said, not all wheat is created equal. Without getting too technical, there are strains of wheat that have more proteins/gluten in it ("hard" wheat) and wheat that has less gluten("soft" wheat). This is partially why different brands of flour don't universally act the same way. Just because you're growing wheat doesn't mean it's going to have the same characteristics as another farmer's wheat. Yeesh!

You may be wondering: so Olivia, what about bleached flour? What's the difference between bleached and unbleached? Enriched?

Industrial-produced flour, like Five Roses and Robin hood, use cast iron grinders to grind the wheat. It's a lot faster and more efficient, however it makes a lot of heat. The heat produced by the milling process destroys some of the nutrients found in the germ and the bran; thus they have to put in additional nutrients ("enriched" flour) to make up for that.

Bleaching/unbleached is a bit more complicated. If you were to get flour from the miller today, you would probably think, "oh boy! Time to make the bestest bread ever with fresh flour!" However, that isn't the case. When flour is exposed to the air it oxidizes and makes the gluten stronger - and also makes the flour more white. This oxidizing process takes a few days or weeks to complete; which usually happens while it's being shipped to your grocery store.

Bleaching is the shortcut way to have white flour. Instead of letting the flour age to turn white and develop the gluten proteins at its own pace, the manufacturer uses bleaching agents and aging agents, such as peroxides and potassium bromate respectively. If you're more conscientious about being organic/reducing the amount of chemicals, you'd probably be more inclined to buy unbleached flour on your next trip to the grocery store. (Totally calling it, by the way)

Fermentation/Proofing

As I covered last time, bread rises because it uses yeast as a leavener; or, in French, levain. This means that yeast eats the sugar and, as a waste product, produces gas (CO2) and alcohol. If we look at the sourdough starter I made, you can see the bubbles of gas made by the yeast.

Now I've been asked this a few times: Olivia, what do you mean there's sugar? Where does it come from? Well, in flour there are two things that are going to help you; an enzyme called amalyse and, of course, yeast.

When you make bread, you put flour; water and yeast. When water is introduced, that's when things start to pick up. Amalyse is an enzyme present in flour and it breaks down starch into simple sugars. Bacteria likes to eat simple sugars, especially yeast. When it's baking in the oven, the enzyme continues to work until it gets too hot; which also allows the yeast to work faster with more sugar until it finally dies off from the heat.

If you're making a wild yeast starter, then the additional bacteria you're concerned about is lactobacillus. While yeast produces gas and alcohol, lactobacillus produces acid: lactic acid and acetic acid. Lactic acid will give the bread more flavour while acetic acid will make it more tangy.

What does it mean when a recipe says to let your dough proof? It's not super complicated; all it means is to let your dough sit while the yeast gets to work. In other words you're fermenting your dough. It might be a little weird to imagine, considering when most people think of fermentation they think of this:

This:

Or everyone's favourite science experiment you find in your fridge:

Totally delicious.

But that's exactly what you're doing when you're proofing your dough. It's fermenting. That being said, during this process you're a) allowing the yeast to do its thing and b) improving the overall flavour of the bread. Since bread making is an art and not a science, you can play around with the fermentation time.

Fast fermentation: Shorter proofing time in a warm place.
This doesn't take as long and you're obviously speeding up the fermentation process. However, the bread is more bland.

Slow fermentation: Long proofing time (usually 8-12hrs) in a cool place.
This allows the bread to develop more complex flavours since the fermentation process is going at a nice, slow pace. However, it obviously stinks to wait 12hours for your bread to do its thing.

Remember that your dough may rise a few times but yeast only rises once. Once it reaches its peak, it's only going to fall from there. In addition to your developed gluten, this will help determine whether your bread is fluffy and airy or dense and chewy.