When you start to learn about making bread you will start to hear about ‘oven spring’ and you might be asking yourself “What is oven spring?”. Well, ask no more.
When a loaf is put in the oven when it is fully proofed it will expand further, up to 30% of its original size, in the first ten minutes of baking. This expansion is called oven spring.
When a loaf is fully proved the carbon dioxide, that is expelled by the yeast as it eats the sugars in the fermentation process, is trapped in the loaf by the web of gluten. The heat of the causes the carbon dioxide to expand and so the loaf expands too as the carbon dioxide pushes against the gluten walls.
How to achieve maximum oven spring
A loaf must be fully proofed to achieve maximum oven spring. Take a look at our article on how to tell when a loaf is fully proved.
If the loaf is under proofed it will still have oven spring but not to the extent that it could have achieved if left to prove for a little longer. You want the loaf to have fully fermented so that there is maximum flavour and maximum carbon dioxide trapped in the gluten to give the bread a light, airy structure. An under proofed loaf will always be a bit dense in the centre of the loaf.
If a loaf is over proofed it is unlikely to achieve much, if any, oven spring. Instead, it is likely to collapse and deflate. An overproved loaf has a weakened gluten structure which can’t contain the carbon dioxide as it expands in the heat and so the loaf just deflates. Imagine a balloon that is blown up so much that it bursts. This is what happens to an over proofed loaf.
Scoring/slashing your loaf to achieve maximum oven spring
Scoring (aka slashing) your loaf is really important if you want to achieve good oven spring. Scoring your loaf allows the loaf to expand at the slash rather than at its weakest point. A scored loaf will expand uniformly and take advantage of the slash to expand. An unscored loaf will have to find room to expand elsewhere and will push through the wall of the loaf at its weakest point creating an unsightly bulge. Take a look at this article to learn how to score your loaf.
Using steam to achieve maximum oven spring
Steaming your oven properly is really important to achieving good oven spring. Steam makes sure that the crust stays moist so that the loaf can rise in the oven. Without steam the crust will harden in the dry heat and expansion won’t be possible.
Take look at my top tips for how to steam your oven. I use a pressurised plant mister for the best control and to fill the oven with steam as I close the oven door after loading the loaf. The best way though is to use a Dutch oven as this creates an enclosed chamber that steam is trapped in creating the perfect environment for achieving great oven spring.
Steam is only needed for the first 10-15 minutes. If you are using a tray of hot water in the bottom of the oven this will need to be removed. If you have chosen a dutch oven you will need to remove the lid to allow for proper browning of the crust.
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Is misting and oven spring specific to sourdough bread or all yeast breads?
I steam all of my loaves, yeasted and sourdough, unless I am baking in a Dutch Oven.
You can read about Dutch ovens here https://vegpatchkitchen.co.uk/using-a-dutch-oven/
Can steam be produced right away when you spray hot water in the oven while closing the cover?