Bread – Is bread that can go mouldy better than that which does not

Gluten is a protein that gives bread elasticity. Water makes gluten spirals relax, and kneading helps stretch the gluten and connect with other gluten strands. Bread that lacks stretchiness:

• may not have enough gluten to start with. If you are using a low gluten flour then you won't get and elasticity. In general any plain white flour will have enough, but for best results use bread flour, also known as strong flour
• may be too dry. Gluten needs water to relax and stretch, if your dough is too dry, or "tight", then you won't get good elasticity
• may have not been worked enough or worked in the wrong way. Kneading mechanically stretches gluten, if it isn't kneaded enough, or the technique isn't right, then no elasticity
• may not have been risen enough. Yeast actually improves the dough, it really works on the gluten. Rise isn't just about leavening, it makes a big difference in elasticity. You should notice a big difference if it's been risen enough

If I had to put money on it I'd say it's probably your dough being too dry. This is an easy mistake to make, you turn your dough out on the counter and it's really gooey, must not have enough flour right? But as gluten get worked it uses up some of the extra moisture, so adding too much flour at the beginning will rob the gluten of the water it needs to relax. Kneading with oil instead of flour may help there.

As an aside, I generally add a couple of tablespoons of olive oil to my pizza dough to improve flavor and texture although that's totally optional. Also, you didn't list salt as an ingredient, bread needs some salt, many bakers recommend 10g per 500g of flour, although I usually cut that down some.

There are three major properties of the liquids:

• Fat based (oil, melted butter, bacon drippings, and on) versus water based (milk, juice, water, and so on).
• Flavor - some liquids, juices and to a lesser extent, milk have a distinct flavor that will effect the bread
• Acid - Some liquids, like orange juice, are more acid and affect the pH of the dough

Not every liquid falls neatly into these exact categories. Milk, for example, is about 87% water, 4% fat, and the rest is sugars and proteins. These differences are often insignificant compared to the overall bread recipe.

In general, you can substitute fat-based liquids for other fat based ingredients, and water based liquids for other water based liquids.

Most breads also have the capacity to carry additional fats and sugars (called enrichment), which at its extreme leads to breads like brioche which are very sweet and fatty.

Eggs are a complex ingredient in that the whites are mostly water, with some protein (albumin), and the yolks are about 50% water and 50% fat.

See related:

Are there any general principles of ingredient substitutions? Note that in a bread recipe, with so few ingredients and a deceptively complex chemistry, all of the ingredients have a role to play in the chemistry, so the major factors you are looking at are the overall total ratios of fat, sugar, and water to the flour. Accent ingredients would be add ins like carway seeds in rye bread which don't incorporate into the dough.

In regards to your desire for more olive oil flavor, you almost certainly can substitute olive oil for any fats already in the recipe with comparable results. Most dought can even carry a little more fat, although this will inhibit yeast growth and gluten development, so that you will need more kneading and more proofing time.

You can also brush the crust with olive oil before or after baking.

The very best way to get olive oil flavor into your bread is to dip it in oil when you eat it. This also allows you to get the full flavor of a quality oil, as many nuances would be lost if it was baked into the bread.