When a loaf of fully risen bread is inserted into a steamy baking environment, the loaf is able to billow or increase its volume largely because a crust hasn’t formed which would harden the exterior and prevent expansion. This principle is instrumental in baking modern bread, particularly the fashionable high-hydration loaves of todays artisan bakers, but also in the initial development of what became known as “French” bread throughout the world. This “French” bread may correctly be referred to as “Vienna” bread, as the process of injecting steam into an oven, or maximising its use in baking was famously pioneered in Vienna along with the use of high protein “hard” bread wheats from Hungary and the Ukraine. Because the formation of a crust is delayed, not only can the loaves billow, but the crust itself has a unique structure. The delay in crust formation is just that, a delay, the crust forms fully when the steam in reduced, but never has the thickness of a crust formed in a “dry” oven. The crust is far thinner and of course crisper. This was seen as elegant and refined in comparison to the thicker and coarser crust formed when bread is baked in a dry environment, or even in the steaminess of a wood-fired brick or stone oven.
This was old knowledge put into play by the Viennese technicians. As excavations in Athens have shown, the use of clay domes (cloche) to cover baking bread was in use in classical times. The principle involved was to make a strong fire, brush aside the coals to reveal a hot earth(hearth) or clay surface , place the loaf on there and quickly cover with a clay dome which had the coals and ashes piled on it. Ive done this when camping and it bakes a fabulous loaf. The initial steam forced from the loaf by heat is eventually dried up and/or escapes through the joints. Which means the ancient Athenians were enjoying well risen loaves with a nice thin but crisp crust…ancient “French” bread. Ive also repeated the process in a modern oven with an earthenware bowl and the result is far superior to simply baking in the dry heat of an oven. The use of a cover or cloche to make good bread was widely in use until the industrial era still, and was also a part of the success of the particular clay ovens which were made in Devon England, and Cornwall. These ovens are of ancient design and were exported widely in colonial times, particularly to the Americas, and widely used in the west country. The ovens could be circular or rectangular and were usually installed in a chimney with the door opening into the kitchen, and were wood-fired. If left free-standing, the coals were raked out and piled on the ovens to ensure plenty of heat. This is essentially the same process which is used with a cloche or the Athenian bread dome.
The advantage of the clay oven is that it is completely sealed. All the initial steam which is instantly generated when the loaves are inserted, stays within the oven ensuring the steamy environment which promises lighter bread. This is different to a metal construction oven wherein the steam instantly escapes, and so has to be regenerated with all manner of artifice. Similarly a well-made commercial size brick oven will retain all of its steam as they were completely sealed. Ive had to open a big brick wood-fired oven just after the loaves were inserted, and narrowly escaped steam burns as the collected steam rushed out. These ovens usually have a small door above the main door, connected to the main chimney which catches this excess steam. But as ive said, this cant be achieved in a metal construction (particularly domestic) oven as the steam readily escapes. Doors on wood-fired ovens are very small to maintain the steam as the oven is being loaded, whereas a modern metal oven usually has very large doors which allow all the steam to escape easily. Ive written about the classic wood-fired Vienna bread oven which was specifically designed to hold steam, and was the technological forerunner of steam injection, a masterful device with an upward sloping sole (hearth/floor) which naturally traps steam.
To replicate and improve upon the steaminess of a good wood-fired oven, modern bakery tech has developed steam injection which allows the loaves to be loaded directly into a steam saturated environment.
With modern breads baked in a steamy oven, the billowing or increase in volume is readily attained, and the thin crisp crust as well, but there is a disturbing aesthetic and that is the shiny crust. As with many modern developments, this is seen fashionably as a virtue with no critical assessment, but to a baker steeped in a traditional or actual “rustic” aesthetic, the shiny crust is gimcrack and “showy” and not actually “rustic” no matter how craft and artisan the manufacture of the bread is. Direct steam injection produces a different crust in another way. As Melbourne baker Iain Banfield pointed out, the steam internally generated in a wood-fired oven is intrinsic to the bread…it has come directly from within the bread and as such is loaded with volatilised aromas, particularly in long ferment and sourdough breads, as the alcohol generated in the fermentation dissolves and carries these aromatic compounds which escape the oven in part eventually, but are largely deposited in the crust, as the alcohol-laden steam further vapourises. Ive always noticed this in the flavour of crust from a good wood-fired oven. These flavour compounds will travel up to a mile from the bakery as is well known in the village situation. When I revived a very old bakery in a village in Australia, and started baking sourdough bread, an older resident noted that he could smell the bread as the oven was unloaded from a mile away!, and hadn’t smelt that for a very long time. In contrast, the steam injected oven develops no such crust flavour, as the aromatic compounds are actually diluted by the flood of steam….and the shiny crust develops. The shiny crust is a result of too much initial steam, but also of prolonged steam. Good bakers use a burst of steam only. The wood-fired oven crust certainly has some shininess, but it is discrete and not overt, which is a much nicer aesthetic.
To push the steam envelope, ive made steamed breads, as chinese bao, but also as larger loaves, and the crust is exceptionally thin and shiny. The interior is nice and cakey from the steam effect, but the crust is a real disappointment, and as the loaf ages, becomes plastic-like and actually unpleasant to chew.
Many of us attempt to create steam in our household ovens, by all sorts of devices including throwing water onto a heated plate, which is almost humorous (not to mention eccentric even barmy!), but can result in steam burns, the nastiest of burns, and is not really “crafty”. The cleverest way to do this came from a customer of Shipton mill on the facebook page. He uses his steam cleaner which generates a lot of steam, to flood his oven when he is loading, producing an admirable loaf.
The ultimate way to achieve a thin crisp crust for the home baker has to be baking in a sealed pot such as a Le Creuset or a cast iron pot. The advantage here is that the loaf can be risen in the pot as well, making the whole process very simple. More on this method later.
Added by: johndownes
Due to unprecedented demand, we have had to close our shop temporarily due to a backlog of orders.
Community bakeries and micro-bakeries can call us directly on 01666 505050 to place orders.
Keep safe and well
The Shipton Millers