Bread Baking – What is a Mother Culture in Baking Bread?

The best approach is to use most of it to make a starter and feed the mother with flour and water for the next bread.

Once you have the mother, you can feed it with as much flour as you need.

Let's say you have 1 cup of mother at 100% hydration. You should use 3/4 cups of it to make a starter for the bread (add flour and water to form a starter your formula suggests). Then, feed the remaining 1/4 cup with 3/8 of both water and flour to make it 1 cup again.

Then, when your starter is active enough (it's better to rest overnight), you can make the bread the same way you do with commercial yeast. Just be sure to calculate the flour and water in the starter for baker percentages.

The numbers are symbolic, it's better to use weight and not volume for correct calculations of baker's percentages.

You can't bake bread to end up without crust, as it will always require high temperatures that will toast the outside (to varying degrees) without just dessicating the entire lump of dough.

For pure crustless bread, I would try to make something like a giant steamed dumpling. There are a few examples (courtesy Jefromi and Jay's comments, respectively) of this in Chinese cooking: baozi, a filled dumpling using yeast dough; or the larger mantou, similar but without filling.

When steaming dough it will retain much more (nearly all) water, so a drier dough would be in order. Generally in most bread-baking, the goal as Julio mentions is to get the inside to 200-210 °F, and by using steam at ~212 °F, you will get virtually no browning.

That said, crust can vary wildly, from very soft to very hard. The softer crust breads I bake are usually done in pans at lower temperatures (325-375 °F) and often contain milk, eggs and or fat. The more "crusty" breads are usually baked quickly at hot temperatures (>450 °F), but if done lower and slower it will change the crust significantly.