Mrs.E. E. Kellogg.

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heat, the result will be a brittle kind of bread termed unleavened
bread, which, although it requires a lengthy process of mastication, is
more wholesome and digestible than soft bread, which is likely to be
swallowed insufficiently insalivated.

The gluten of wheat flour, beside being adhesive, is likewise remarkably
elastic. This is the reason why wheat flour is much more easily made
into light bread than the product of other cereals which contain less or
a different quality of gluten. Now if while the atoms of flour are
supplied with moisture, they are likewise supplied with some form of
gaseous substance, the elastic walls of the gluten cells will become
distended, causing the dough to "rise," or grow in bulk, and at the same
time become light, or porous, in texture.

This making of bread light is usually accomplished by the introduction
of air into the dough, or by carbonic acid gas generated within the
mass, either before or during the baking, by a fermentative or chemical
process.

When air is the agency used, the gluten, by its glue-like properties,
catches and retains the air for a short period; and if heat is applied
before the air, which is lighter than the dough, rises and escapes, it
will expand, and in expanding distend the elastic glutinous mass,
causing it to puff up or rise. If the heat is sufficient to harden the
gluten quickly, so that the air cells throughout the whole mass become
firmly fixed before the air escapes, the result will be a light, porous
bread. If the heat is not sufficient, the air does not properly expand;
or if before a sufficient crust is formed to retain the air and form a
framework of support for the dough, the heat is lessened or withdrawn,
the air will escape, or contract to its former volume, allowing the
distended glutinous cell walls to collapse; in either case the bread
will be heavy.

If carbonic acid gas, generated within the dough by means of
fermentation or by the use of chemical substances, be the means used to
lighten the mass, the gluten by virtue of its tenacity holds the bubbles
of gas as they are generated, and prevents the large and small ones from
uniting, or from rising to the surface, as they seek to do, being
lighter than the dough. Being thus caught where they are generated, and
the proper conditions supplied to expand them, they swell or raise the
dough, which is then termed a loaf. (This word "loaf" is from the
Anglo-Saxon _hlifian_, to raise or lift up.) The structure is rendered
permanent by the application of heat in baking.


BREAD MADE LIGHT BY FERMENTATION.

For general use, the most convenient form of bread is usually considered
to be that made from wheat flour, raised or made light by some method of
fermentation, although in point of nutritive value and healthfulness, it
does not equal light, unfermented, or aërated bread made without the aid
of chemicals.

THE PROCESS OF FERMENTATION. - Fermentation is a process of
decomposition, and hence more or less destructive to the substances
subjected to its influence. When animal and vegetable substances
containing large amounts of nitrogenous elements are in a moist state
and exposed to air, they very soon undergo a change, the result of which
is decomposition or decay. This is occasioned by the action of germs,
which feed upon nitrogenous substances, as do the various species of
fungi. Meat, eggs, milk, and other foods rich in nitrogenous elements
can be preserved but a short time if exposed to the atmosphere. The
carbonaceous elements are different in this respect. When pure starch,
sugar, or fat is exposed to the air in a moistened state, they exhibit
the very little tendency to change or decay. Yet if placed in contact
with decomposing substances containing nitrogen, they soon begin to
change, and are themselves decomposed and destroyed. This communication
of the condition of change from one class of substances to another, is
termed fermentation. If a fermenting substance be added to a watery
solution containing sugar, the sugar will be changed or decomposed, and
two new substances, alcohol and carbonic acid gas, are produced.

The different stages of fermentation are noted scientifically as
alcoholic, acetous, and putrefactive. The first is the name given to the
change which takes place in the saccharine matter of the dough, which
results in the formation of alcohol and carbonic acid gas. This same
change takes place in the saccharine matter of fruits under the proper
with conditions of warmth, air, and moisture, and is utilized in the
production of wines and fermented liquors.

In bread-making, the alcohol and carbonic acid gas produced during the
fermentation, are formed from sugar, - that originally contained in the
flour and the additional quantity formed from starch during the
fermenting process. It is evident, therefore, that bread cannot be
fermented without some loss in natural sweetness and nutritive value,
and bread made after this method should be managed so as to deteriorate
the material as little as possible.

If this fermentation continues long enough, the acetous fermentation is
set up, and _acetic_ acid, the essential element of vinegar, is formed
and the dough becomes sour. If the process of fermentation is very much
prolonged, the putrefactive change is set up, and the gluten is more or
less decomposed.

If the dough be baked during the alcoholic and carbonic-acid stage of
fermentation, the gas will render the loaf light and porous. The alcohol
will be dissipated by the heat during the baking, or evaporated shortly
afterward, provided the baking be thorough. If the fermentation is
allowed to proceed until the acetous fermentation has begun, the loaf,
when baked, will be "sad" and heavy, since there is no longer any gas to
puff it up. If, however, during the first or alcoholic stage of
fermentation, new material be added, the same kind of fermentation will
continue for a certain period longer.

These facts serve to show that great care and attention are necessary to
produce good bread by a fermentative process. If the fermentation has
not been allowed to proceed far enough to generate a sufficient amount
of gas to permeate the whole mass, the result will be a heavy loaf; and
if allowed to proceed too far, acid fermentation begins, the gas
escapes, and we have sour as well as heavy bread. It is not enough,
however, to prevent bread from reaching the acetous or sour stage of
fermentation. Bread may be over-fermented when there is no appreciable
sourness developed. Fermentation may be carried so far as to destroy
much of the richness and sweetness of the loaf, and yet be arrested by
the baking process just before the acetous stage begins, so that it will
be light and porous, but decidedly lacking in flavor and substance.
Over-fermentation also develops in the bread various bitter substances
which obscure the natural sweetness of the bread and give to it an
unpleasant flavor. Many of these substances are more or less harmful in
character, and include many poisons known as ptomaines, a class of
chemical compounds produced by germs whenever fermentation or
decomposition of organic matter takes place. Much skill is required to
determine at what point to arrest the fermentation, in order to save the
sweetness and richness of the bread.

FERMENTATIVE AGENTS. - Fermentation in vegetable matter is always
accompanied by the growth of living organisms. The development of these
minute organisms is the exciting cause of fermentation and putrefaction.
The germs or spores of some of these fermenting agents are always
present in the air. It is well known to housekeepers that if a batter of
flour and water and a little salt be kept in a jar of water at a
temperature of from 100° to 110°, it will ferment in the course of five
or six hours. Scientists assure us that this fermentation is occasioned
by the introduction of the spores of certain species of fungi which are
continually floating in the atmosphere, and the proper conditions of
warmth and moisture being supplied, they at once begin to grow and
multiply. This method of securing fermentation is utilized by housewives
in making what is termed salt-rising bread. The raising of dough by this
process is lengthy and uncertain, and a far more convenient method is to
accelerate the fermentation by the addition of some active ferment. The
ancient method of accomplishing this was by adding to the dough a
leaven, a portion of old dough which had been kept until it had begun to
ferment; but since the investigations of modern chemistry have made
clear the properties of yeast, that has come to be considered the best
agent for setting up the process of alcoholic fermentation in bread. The
use of leaven is still practiced to somewhat in some European countries.
The bread produced with leaven, although light and spongy in texture,
has an unpleasant, sour taste, and is much less wholesome than that
produced with fresh yeast.

Yeast is a collection of living organisms or plants belonging to the
family of fungi, which, like all other plants, require warmth, moisture,
and food, in order to promote growth, and when properly supplied with
these, they begin to grow and multiply rapidly. Fermentation will not
take place at a temperature below 30°, it proceeds slowly at 45°, but
from 70° to 90° it goes on rapidly. Fermentation may be arrested by the
exhaustion of either the fermenting agent or the food supply, or by
exposure to heat at the temperature of boiling water. This latter fact
enables the housewife to arrest the process of fermentation, when the
loaf has become sufficiently light, by baking it in a hot oven. Heat
destroys most of the yeast cells; a few, however, remain in the loaf
unchanged, and it is for this reason that yeast bread is considered less
wholesome for dyspeptics than light unleavened bread. It is apparent,
then, that the more thoroughly fermented bread is baked, the more
wholesome it will be, from the more complete destruction of the yeast
germs which it contains.

YEAST. - Next to good flour, the most important requisite in the
manufacture of fermented bread is good yeast. The best of flour used in
conjunction with poor yeast will not produce good bread. The most
convenient and reliable kind of marketable yeast, when fresh, is the
compressed yeast. The dry though they are always ready for use, the
quality of the bread they produce is generally inferior to that made
with either compressed yeast or good liquid yeast. If this sort of yeast
must be depended upon, the cakes known as "Yeast Foam" are the best of
any with which we are acquainted.

Of homemade yeasts there are almost as many varieties as there are
cooks. Their comparative value depends mainly upon the length of time
they will keep good, or the facility with which they can be prepared.
Essentially the same principles are involved in the making of them all;
viz., the introduction of a small quantity of fresh, lively yeast into a
mixture of some form of starch (obtained from flour, potato, or a
combination of both) and water, with or without the addition of such
other substances as will promote fermentation, or aid in preventing the
yeast from souring. Under proper conditions of warmth, the small amount
of original yeast begins to supply itself with food at once by
converting the starch into dextrine, and then into grape sugar, and
multiplies itself with great rapidity, and will continue to do so as
long as there is material to supply it with the means of growth. While
its growth is rapid, its decay is equally so; and unless some means of
preservation be employed, the yeast will die, and the mixture become
sour and foul. Ordinarily it can be kept good for several days, and
under the best conditions, even three or four weeks. After it has been
kept from four to six hours, it should be placed in some receptacle as
nearly air-tight as possible and set in the cellar or refrigerator,
where it can be kept at a temperature not conducive to fermentation.
Thus the little yeast organisms will remain in a quiescent state, but
yet alive and capable of multiplying themselves when again surrounded
with favorable conditions.

The yeast should be kept in glass or glazed earthen ware. The vessel
containing it should be washed and scalded with scrupulous care before
new yeast is put in, since the smallest particle of sour or spoiled
yeast will ruin the fresh supply in a very short time. It is generally
conceded that yeast will keep longer if the material of which it is made
be mixed with liquid of a boiling temperature, or cooked for a few
minutes at boiling heat before adding the yeast. The reason for this
undoubtedly lies in the fact that the boiling kills foreign germs, and
thus prevents early souring or putrefaction. The yeast must not be
added, however, until the liquid has cooled to a little more than blood
heat, as too great heat will kill the yeast cells.

The starch of the potato is thought to furnish better material for the
promotion of yeast growth than that of wheat flour; but whether the
potato be first cooked, mashed, and then combined with the other
ingredients, or grated raw and then cooked in boiling water, makes
little difference so far as results are concerned, though the latter
method may have the advantage of taking less time. If potatoes are used
for this purpose, they should be perfectly mature. New ones will not
answer.

Sugar assists in promoting the growth of the yeast plant, and a small
amount is usually employed in making yeast. Hops serve to prevent the
yeast from souring, and an infusion of them is frequently used for this
purpose.

While it is essential that the water used should be boiling, it is also
necessary that the mixture should cooled to a lukewarm temperature
before the introduction of the original yeast, as intense heat will kill
the yeast plant. Freezing cold will likewise produced the same result.
While a cool temperature is one of the requisites for keeping yeast
fresh, care must be taken, especially in winter, that it does not get
chilled.

When yeast is needed for bread, it is always the best plan to take a cup
to the cellar or refrigerator for the desired quantity, and re-cover the
jar as quickly as possible. A half hour in a hot kitchen would be quite
likely to spoiled it. Always shake or stir the whole well before
measuring out the yeast. In making yeast, used earthen bowls for mixing,
porcelain-lined or granite-ware utensils for boiling, and silver or
wooden spoons for stirring.

BITTER YEAST. - It sometimes happens that an excessive use of hops
in the making of yeast gives to it so bitter a flavor as to communicate
a disagreeable taste to the bread. To correct this bitterness, mix with
the yeast a considerable quantity of water, and let it stand for some
hours, when the thickest portion will have settled at the bottom. The
water, which will have extracted much of the bitterness, can then be
turned off and thrown away. Yeast also sometimes becomes a bitter from
long keeping. Freshly burnt charcoal thrown into the yeast is said to
absorb the odors and offensive matter and render the yeast more sweet;
however, we do not recommend the use of any yeast so stale as to need
sweetening or purifying. Yeast that is new and fresh is always best; old
and stale yeast, even though it may still possess the property of
raising the dough, will give an unpleasant taste to the bread, and is
much less wholesome.

TESTS FOR YEAST. - Liquid yeast, when good, is light in color and
looks foamy and effervescent; it has a pungent odor somewhat similar to
weak ammonia, and if tasted will have a sharp, biting flavor. Yeast is
poor when it looks dull and watery, and has a sour odor. Compressed
yeast, if good, breaks off dry and looks white; if poor, it appears
moist and stringy.

If there is any question as to the quality of yeast, it is always best
to test it before use by adding a little flour to a small quantity and
setting it in a warm place. If it begins to ferment in the course of
fifteen or twenty minutes, it is good.

STARTING THE BREAD. - Having secured good yeast, it is necessary in
some way to diffuse it through the bread material so that it will set up
an active fermentation, which, by the evolution of gas, will render the
whole mass light and porous. As fermentation is more sure, more rapid,
and requires less yeast to start it when set in action in a thin mixture
than when introduced into stiff dough, the more common method of
starting fermented bread is by "setting a sponge;" viz., preparing a
batter of flour and liquid, to which potato is sometimes added, and into
which the yeast is introduced. Some cooks, in making the batter, use
the whole amount of liquid needed for the bread, and as the sponge
rises, add flour in small quantities, beating it back, and allowing it
to rise a second, third, or even fourth time, until sufficient flour has
been added to knead; others use only half the liquid in preparing the
sponge, and when it has well risen, prepare a second one by adding the
remainder of the liquid and fresh flour, in which case the fermented
batter acts as a double portion of yeast and raises the second sponge
very quickly. The requisite amount of flour is then added, the dough
kneaded, and the whole allowed to rise a third time in the loaf. Other
cooks dispense altogether with the sponge, adding to the liquid at first
the requisite amount of flour, kneading it thoroughly and allowing it to
rise once in mass and again after molding into loaves. As to the
superiority of one method over another, much depends upon their
adaptability to the time and convenience of the user; light bread can be
produced by either method. Less yeast but more time will be required
when the bread is started with a sponge. The end to be attained by all
is a complete and equal diffusion of gas bubbles generated during
fermentation throughout the whole mass of dough.

The preferable method of combining the materials needed for the batter
is by first mingling the yeast with the water or milk. If condensed or
dry yeast is used, previously dissolve it well in a half cupful or less
of lukewarm water. Stir the flour slowly into the liquid mixture and
beat it _very thoroughly_ so that the yeast shall be evenly distributed
throughout the whole.

PROPORTION OF MATERIALS NEEDED. - The material needed for making:
the bread should all be carefully measured out beforehand and the flour
well sifted. Many housekeepers fail in producing good bread, because
they guess at the quantity of material to be used, particularly the
flour, and with the same quantity of liquid will one time use much more
flour that at another, thus making the results exceedingly variable.
With this same brand of flour, this same quantity should always be used
to produce a given amount of bread. This amount will depend upon the
quality of the material used. Good flour will absorb a larger quantity
of liquids than that of an inferior quality, and the amount of liquid a
given quantity of flour will take up determines the quantity of bread
that can be produced from it. This amount is chiefly dependent upon the
proportion of gluten contained in the flour. One hundred pounds of good
flour will absorb sufficient water to produce one hundred and fifty
pounds of bread. One reason why bread retains so much water is that
during the baking a portion of starch is converted into gum, which holds
water more strongly than starch. Again: the gluten, when wet, is not
easily dried, while the dry crust which forms around the bread in baking
is merely impervious to water, and, like the skin of a baking potato,
prevents the moisture from escaping.

Kinds of flour vary so considerably in respect to their absorbent
properties that it is not possible to state the exact proportions of
flour and liquid required; approximately, three heaping measures of
flour for one scant measure of liquid, including the yeast, will in
general be found a good proportion. Bread made from the entire wheat
will require from one half to one cupful less flour than that made of
white flour. A quart of liquid, including the yeast, is sufficient for
three ordinary-sized loaves. One half or two thirds of a cup of homemade
yeast, according to its strength, or one half a cake of compressed yeast
dissolved in a half cup of lukewarm water, will be sufficient for one
quart of liquid. It is a common mistake to use too much yeast. It
lessens the time required, but the result is less satisfactory. Bread to
be set over night requires less yeast.

Whether water or milk should be used for bread-making, depends upon
taste and convenience. Bread retains more nearly the natural flavor of
the grain if made with water, and is less apt to sour; at the same time,
bread made with milk is more tender than that made with water. Bread
made with milk requires from one half to one cupful less of flour.

Potatoes are sometimes used in conjunction with flour for bread-making.
They are by no means necessary when good flour is used, but bread made
from inferior flour is improved by their use. Only potatoes that are
fully matured should be used for this purpose, and they should be well
cooked and smoothly mashed. Neither sugar nor salt is essential for the
production of good bread, though most cook books recommend the use of
one or both. The proportion of the former should not exceed one even
tablespoonful to three pints of flour, and the very smallest amount of
salt, never more than a half teaspoonful, and better less. No butter or
other free fat is required; the tenderness of texture produced by its
use can be secured as well by the use of unskimmed milk and thorough
kneading.

UTENSILS. - For bread-making purposes, earthen or china ware is
preferable to either tin or wooden utensils: being a poor conductor, it
protects the sponge from the cold air much more effectually than tin,
and is much more easily kept clean and sweet than wood. The utensil
should be kept exclusively for the purpose of bread-making, and should
never be allowed to contain any sour substance. The bowl should be
thoroughly scalded before and after each using. Use silver or
granite-ware spoons for stirring the bread. Iron and tin discolor the
sponge. For measuring the material, particularly the liquid and the
yeast, half-pint cups, divided by marks into thirds and fourths, as
shown in the cut, are especially serviceable.

[Illustration: Measuring Cup] [Illustration: Measuring Cup]

WHEN TO SET THE SPONGE. - The time to set the sponge for
bread-making is a point each housekeeper must determine for herself. The
fact before stated, that temperature controls the activity of
fermentation, and that it is retarded or accelerated according to the
conditions of warmth, enables the housewife, by keeping the
bread-mixture at a temperature of about 50° F., to set her bread in the
evening, if desired, and find it light and ready for further attention
in the morning. In winter, the sponge will need to be prepared early in
the evening and kept during the night at as even a temperature as
possible. A good way to accomplish this is to cover the bowl with a
clean napkin and afterwards wrap it about very closely with several
folds of a woolen blanket. In extremely cold weather bottles of hot
water may be placed around the bowl outside the wrappings. In case this
plan is employed, care must be taken to have sufficient wrappings
between the bread and the bottles to prevent undue heat, and the bottles
should be covered with an additional blanket to aid in retaining the
heat as long as possible.

If the sponge is set in the evening, if in very warm weather, it should
be started as late as practicable, and left in a rather cool place.
Cover closely to exclude the air, but do not wrap in flannel as in
winter. It will be likely to need attention early in the morning.

TEMPERATURE FOR BREAD-MAKING. - Except in very warm weather, the
ferment or sponge should be started with liquid at a lukewarm
temperature.

The liquid should never be so cold as to chill the yeast. Milk, if used,
should be first sterilized by scalding, and then cooled before using.

After the sponge is prepared, the greatest care must be taken to keep it
at an equable temperature. From 70° to 90° is the best range of
temperature, 75° being considered the golden mean throughout the entire
fermentative process of bread-making.

After fermentation has well begun, it will continue, but much more
slowly if the temperature be gradually lowered to 45° or 50°. If it is
necessary to hasten the rising, the temperature can be raised to 80° or



Online LibraryMrs.E. E. KelloggScience in the Kitchen → online text (page 11 of 54)