Subject: 19. How do I get that great crust?
It is difficult to reproduce the effects of a commercial hearth oven at home. The properties of a good oven include thick baking stones on the bottom preferably heated with gas fire for more even heat distribution than electric coils. The oven should have heating elements at the top of the oven and controls for setting the heat intensity in all areas of the oven.
The most important difference between baking bread in a commercial hearth oven and at home, is that the commercial oven has steam tubes which deliver large amounts of steam at a reasonable pressure. Steam gelatinizes the starch and protein on the exterior of the loaves without forming a hard shell. After the steam is removed, the gelatinized layer dries out forming a thick crunchy crust. With no steam, it is more difficult to keep the exterior of the bread from forming a paper thin shell.
Another important difference is that the commercial deck oven is not very tall from top to bottom which makes the heat more intense than in a home oven. The thickness of the baking stones also acts as a heat sink to deliver maximum heat to the bread before the crust begins to form resulting in better volume. In a home oven, a thin layer of steam surrounds the bread and prevents efficient transfer of heat to the bread. Convection ovens work better.
A few things can be done at home to better simulate a true deck oven. Get a good thick baking stone and of course put it in the oven long before you intend to put bread on it. Put the stone as close to the top of the oven as you can still leaving room for the bread to rise. That will give more intense heat. To simulate quality steam, spray the bread well with water just before baking. I use another strange gadget that works very well. I take aluminum muffin tins and poke tiny holes in the bottom of each well. I fill the tins with boiling water and place them on the bottom rung of the oven about a minute before putting the bread in to develop initial steam. The water will drip onto the bottom of the oven and create steam. Remove the tins after the first 5-10 minutes or the bread will develop an undesirable crust. Also, I heat my oven about 50 F higher than i need because the water evaporation cools the oven. Depending on the oven this method works pretty well.
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