bk-ovn.txt

bk-ovn.txt - - - - wood fired brick ovens 2001

BodyArticle for The Bakers Guild Newsletter, Alan Scott, 3/29/01, 1663 words
WOOD FIRED BRICK OVENS
There are two bakers in the USA whose bread is just exponentially outstanding;
immediately I bite into a slice my awe is akin to what I feel in the presence of
great art. More than twenty odd years ago, however, it was more astonishment for
me than awe when I experienced Laurel Robertson's loaves of sourdough whole
wheat Flemish "Desem" bread baked for the first time in a brick oven. Any
puritanical notions that healthy whole grain bread had to be stodgy left me for
good, for here were those same previously bland gas oven baked "healthy"
sourdough loaves now miraculously colorful, radiant, fragrant, with a delectable
soft moist crumb, irresistible, yet still just as nourishing and good for you.
This experience was certainly the turning point for me as an artisan, leaving
off ornamental blacksmithing and other traditional crafts I began researching
and building wood fired brick bread ovens and baking the "Desem" bread in them.
Today these ovens have a very specific part to play in the process of creating
exceptional bread and have become the tool of choice of individual artisan
bakers like the two mentioned above who have mastered their art like few others.

WHAT IS A BRICK OVEN
A brick oven has a baking chamber that is primarily made of dense clay fire
bricks which are heated first and whose heat then bakes the loaves placed in
them.
Over the years there have been a variety of designs but those of most interest
to the artisan hearth bread baker will have low ceilings and be heated in the
chamber itself. The simplest and oldest of this type has a single door and flue
at the front and is fired in the same chamber as the bread is baked in. These
ovens can be fired very hot and the baking chamber can be tightly sealed during
baking. With modern materials and thoughtful design these ovens are very fuel
efficient and one firing will heat them enough for multiple batches of bread,
over 16 has been achieved at one bakery. Doughs are tailored to make the most of
the incredible high heat at the beginning and the descending heat throughout the
day. In a community oriented micro bakery this fits nicely with baking the
variety of goodies that is expected of them. They are inexpensive to construct
but are limited in size and relatively short lived, 20 years perhaps, because
the bake chamber is also the fire box. These ovens are however a good way to get
inspired and get going on a small scale especially as it is possible to build
ones own at a very low cost.
More complex, larger and much more expensive are the French style ovens that are
also low domed but fired instead from a firebox underneath. From the firebox
shoots a flame into the chamber which then exits through an elaborate duct
system. Ovens of this type up to 18' deep are still in use here in the USA. They
require firing after every batch or two of bread, and using gas rather than wood
is now common
There are many other more elaborate brick ovens from the last century still in
use and still being constructed but most of these were not specifically designed
for hearth baking but more for production, for consistency, for yeasted pan
loaves, and certainly with little consideration for individual artistic
expression. Similar but not included here are the rotating "brick" ovens that
actually have a concrete hearth turning within a steel chamber. These are
popular today with small production bakeries but are limited, as are most all
modern ovens, by their inability to be heated to very high temperatures and by
the low intensity of their heat.
THE HEAT
It is the intensity of the heat that makes a brick oven bake bread differently
from most other ovens, and the masonry that holds the heat can be heated very
much hotter than other ovens. The heat is very intense because it is radiated,
conducted and convected all at one and the same time. It is perhaps the radiated
heat that is outstanding in a brick oven, with the conducted heat directly from
the hearth also a major contributing factor as both penetrate even the moistest
doughs instantaneously and bake them through rapidly without unduly drying or
scorching the crusts.
At the other end of the temperature scale this same heat bakes through a dough
at much lower than usual temperatures without excessive drying and crusting.
This is unlike most modern ovens, excepting expensive hearth type ovens, whose
heat is exchanged mostly through the convection of hot gasses, a relatively slow
process. In a brick oven it is the radiated and conducted "macrowave" heat that
allows baking at such an extended range of temperatures without the scorching
and drying and the astute artisan can make use of this extended heat range to
great effect.
THE CRUST
There are great expectations about the crust coming from a brick oven but
initially there can be disappointment when one expects the usual shiny, reddish,
thick crispy crusts of the modern loaf to be now even glossier, a richer red,
thicker and crisper than ever. Not so. The brick oven crust is formed by the
effect of the steamy environment of its sealed chamber. During hand loading a
little extra mist is advisable introduced into the chamber at the start, but not
so excessive as to create blistering, for after a short time the loaves begin to
gently steam themselves. This steam helps keep the dough pliable during its
final spring, just as pure steam does in any oven, but since this steam rises
out of the dough itself and does not escape from the chamber, it eventually
settles back on the bread condensing out all the flavors of the complex
fermentation processes onto the crust. Since taste is 80% smell detected in the
nasal passages, these crusts have an immediate piquant appeal. Add to this the
possibility of controlled charring and caramelizing in the intense heat and yet
another dimension can be added as well to the look and taste of a loaf and to
each slice.
Surprisingly, brick oven crusts often end up as thin and pliable as the best
suede leather, a tough skin excellent for protecting the precious crumb within
and preventing dehydration for days.
THE ECONOMICS
A well insulated internally fired oven will hold heat for bread baking for a
twelve or more hour period which begins with an extra hot oven and ends with
more gentle heats at the end of the bake day. These contemporary ovens are
dramatically different than their traditional counterparts in their fuel
efficiency and in their ease of use. Design improvements and particularly
insulation technology has allowed these oven chambers to be saturated to
temperatures twice that required for baking so that this heat is there in
reserve deep in the masonry for a full day of bread baking from just the one
evening fire. It has been recorded recently that a small brick oven with a
single hearth of 22 square feet baked 630 lbs. of dough using 120 lbs. of mixed
hard and soft woods, that is about 5 lbs. of bread for every 1 lb. of wood. This
is close to getting the maximum btu's out of wood fuel according to science, and
particularly interesting just as gas prices are skyrocketing.
In contrast the large French type ovens maintain less than baking temperatures
in their great mass so must be re-heated between each batch of bread with a
flash fire. This can give the baker the exact heat he needs and allows for
continuous round the clock baking if necessary. This heat is also initially high
and then descending through each batch which some believe to be the ideal for
bread baking and perhaps explains the universal acclaim that classic French
breads receive.
TIME AND MATERIALS
A small outdoor oven built on weekends can cost as little as a few hundred
dollars but as one gets into commercial sizes the costs grow. An outdoor home
oven need only have its flue a safe distance from other buildings, 10 feet,
perhaps meet local ordinances, 6 feet in height for example in our particular
area, and have a sound enough footing to carry considerable weight. Built
indoors there are more fire and building codes to meet and real concerns with
footings and flues both of which can add considerably to the costs. These ovens
unlike pizza ovens are thick and very well insulated so they need much more room
than usually expected and built indoors usually require the services of an
architect and a professional mason. Costs can exceed $5000 when built
professionally.
In a commercial setting add health codes to the building and fire codes that
must be met by each oven on site during the construction process. These ovens
are not appliances with NSF or UL numbers. The environmental concerns from wood
burning are minimal since these ovens are clean burning and well within industry
standards for emissions, but be prepared for potential costly alternative
venting arrangements if hoods, Ansel systems or scrubbers are demanded by an
overly cautious department. Allow $15000 for the basic cost of a commercially
oven with a 48"x 72" hearth mentioned above for example, and more as size
increases and decorative finish becomes more elaborate or as foundation and flue
demands. These ovens can weigh 7-10 tons but even so many of them have been
partly dismantled and moved in the past as they were originally designed to do.
At worst just a day or two could see the largest oven totally demolished.
ON THE SLICING EDGE
Besides the phenomenal crusts, perhaps the most significant advantage to using a
brick oven in recent times has been that bakers are again able to bake slacker
naturally leavened doughs, and this has precipitated a radical chain reaction.
First it has encouraged a return to low gluten flours that perform so well when
developed using the autolyse process as wet doughs. Secondly these softer flours
as wetter doughs result in a softer, moister crumb. Third, this crumb (which can
be as soft as any), is likely to be very much more fragrant since these softer
wheats, unlike the modern high gluten hybrids, are often distinctly perfumed.
Fourth, low gluten soft flours often come from older varieties of wheat which
are adapted to more temperate climates so these can again be grown closer to
major population centers for example, closer then to home and to small community
oriented bakeries. Finally, any local grain growing will stimulate a return to
local "artisan" milling, all of which in fact is already happening.
Have you wondered all these years why one persistent voice from the past states
that stone ground flour is the best? Well it is, if: the wheat is a little soft,
the mill is a large one with natural stones, the mill stones turn slowly, the
flour stays between the stones long enough for the germ oils to be thoroughly
rubbed into the fabric of the flour, the flour is not overheated, some of the
larger bran particles are sifted off at the end of the milling, you use the
flour within a few hours (preferably a few minutes) of its milling, your doughs
are naturally leavened and very wet, and you bake your bread in the tightly
sealed chamber of a hot brick oven. This then makes bread that will be
remembered for a long, long time.

-no end-