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ROPE AND MOLD
||Cause and Source of Infection
||Rope is Caused by the Bacillus Mesentericus
||Former Exaggerated Views Regarding Rope Infection
||Rope Organisms Prevalent in Air and Dust
||Yeast Can Not Carry Rope Organisms
||Importance of Understanding the Cause and Prevention of Rope
||Evidence and Characteristics of Rope
||Odor and Taste of Loaf
||Discoloration of Crumb
||Stickiness of Crumb
||“Foxy” Crust Color
||A Method for Detecting Rope
||General Precaution Measures Against Rope
||Use of Vinegar
||Removal of Stale Bread
||Storage Conditions for Raw Materials
||Healthy Vigorous Panary Fermentation
||Cooling and Wrapping of Bread
||Storage of Bread
||Immediate Steps to Be Taken When Rope Appears
||Exercise All Precautionary Measures
||Changes in Dough Batch,—Conditioning—Baking and Bread Cooling
||Vinegar in doughs
||Reduction in sugar
||More age on doughs
||Cooling and wrapping
||Methods of Eliminating Rope Infection Throughout the Bakery
||Live steam—treatment of shop and equipment
||(a) Washing of floors with formaldehyde solution
||(b) Fumigating with formaldehyde
||Investigation of Source of Rope in the Bakery
||Examination of Material
||Baking Test Method
||General Preliminary Procedure
||Examination of Check and Test Loaves
||Both sets of loaves exhibiting ropiness
||None of the loaves exhibiting ropiness
||The case of the development of rope only in the test dough
||Importance of Confirmation of Baking Tests by Bacteriological Examination
||Mold Defined and Explained
||The Growth and Distribution of Molds
||Protective Measures Against Mold
||Baking, Cooling and Wrapping of Bread
||Filtered and Washed Air in the Bakery
||Mold in Bread Cannot Be Caused by the Ingredients Used
ROPE AND MOLD
I. ROPE DEFINED
Rope is the name given to a bread disease which results in
breaking down the starch and protein of the loaf producing a discolored and
sticky condition in the crumb which is accompanied by a characteristic
disagreeable odor and nauseating taste. Ropiness in bread is not noticeable
directly after baking but usually makes its appearance from 12 to 36 hours
after the bread has left the oven. This bread disease most always occurs during
the hot humid months and very rarely during cold winter months.
II. CAUSE AND SOURCE OF INFECTION
A. ROPE IS CAUSED BY THE BACILLUS MESENTERICUS
Rope in bread is caused directly by the growth and
development of micro-organisms belonging to the group known as the “bacillus
mesentericus” and commonly spoken of as the “rope bacillus.”
The rope bacillus is a tiny rod shaped organism which
can only be seen by means of the microscope. The rope bacillus is generally
present in a special form known as spores. These rope spores are quite
resistant to heat and when contained in bread doughs they can pass thru the
oven without being killed and hence are able to develop and grow later on in
the baked loaf.
The rope bacillus occurs naturally in the soil and is
most frequently present on the outer part of vegetables and grains. This
organism is quite generally carried by the potato and for a long
time it was spoken of as the potato bacillus.
B. FORMER EXAGGERATED VIEWS REGARDING ROPE INFECTION
Formerly, many exaggerated views were held concerning
the manner in which bread doughs became infected with the rope organisms. Many
people believed that rope would only develop in unclean bakeries and when this
disease became apparent, they were very likely to immediately blame the flour
as the source of infection. However, an intensive study concerning rope and its
development in bread has yielded much enlightening information correcting some
of these former views. In some instances, rope has developed in clean bakeries
and in many cases it has been found that the flour could not be condemned as
the basic cause of this condition.
C. ROPE ORGANISMS PREVALENT IN AIR AND DUST
The rope organisms like other bacteria and mold spores
are present to a certain extent practically everywhere in the air and carried
by dust particles. If conditions are not particularly favorable to their
growth, and they do not occur in abundance, they will not produce any apparent
evidence of ropiness.
While flour and certain other raw materials in the
bakery may become infected with rope organisms, it is not correct to
immediately attribute the source of rope to the flour unless a careful and
thorough investigation proves this to be the case.
D. YEAST CAN NOT CARRY ROPE ORGANISMS
Incidentally the rope organism will not develop under
mildly acid conditions. Because of the fact that yeast is grown on a slightly
acidified media, it is obvious that yeast cannot become a carrier of the rope
organism. In like manner, the source of rope infection cannot be traced to
those malt extracts which contain a small percentage of acid.
E. IMPORTANCE OF UNDERSTANDING THE CAUSE AND PREVENTION OF ROPE
In view of the fact that rope is a condition which may
appear even in well regulated bakeries and because this bread disease can steal
a baker’s business from him like a thief in the night, it is very important for
every baker to become familiar with the nature of rope, the conditions which
favor its development as well as measures which should be taken to prevent its
occurrence and to eliminate it directly after it has first become noticeable.
Therefore, this general subject is discussed further in the following
III. EVIDENCE AND CHARACTERISTICS OF ROPE
A. ODOR AND TASTE OF LOAF
The first indication of a ropy condition in bread is
usually the detection of a peculiar unpleasant odor and taste of the loaf
resembling that of over-ripe cantaloupe.
This odor and taste is faint during the early stages
of the development of rope but becomes stronger and more obnoxious as the rope
Rope usually becomes first apparent in the center of
the loaf and later spreads throughout the entire loaf.
B. DISCOLORATION OF CRUMB
In addition to the characteristic odor developed, rope
in bread results in a gradually darkening of the crumb which eventually becomes
dark brown. This discoloration usually becomes evident in the center of the
loaf and gradually spreads through the entire interior of the loaf.
C. STICKINESS OF CRUMB
One very significant indication of rope in bread is
the development of a sticky, viscous condition of the crumb. If a small portion
of the crumb is pressed between the fingers and then pulled apart, it will
sometimes stretch readily into long silky strands of web-like threads. This is
undoubtedly the reason why this bread disease has been named “rope.”
D. “FOXY” CRUST COLOR
The crust of a “Ropy” loaf frequently exhibits a
“foxy” or peculiar reddish color.
IV. A METHOD FOR DETECTING ROPE
Rope is readily detected by the baker thru the
manifestation of the peculiar characteristics and unmistakable evidences of
rope described above.
Every baker should maintain a continual “look-out” for the
appearance of rope especially during hot humid weather. This can be done as
Three or four loaves of bread should be selected at random
from each day’s baking. These loaves should be stored under relatively warm and
moist conditions so that if rope is liable to become evident in these
particular loaves, it will have the conditions which are most favorable for its
development. One loaf should be cut and carefully examined about 12 to 18 hours
after baking and another 24 hours later, and still another one day after
this,—thus covering a total period of about 3 days. If the odor or appearance
of any of these loaves indicates the development of rope, immediate steps should
be taken to remedy the situation. Frequently in this way the baker will be able
to observe the occurrence of rope through the detection of a faint “ropy” odor
before it becomes very pronounced. Thus the baker can take the necessary steps
to prevent rope development in other dough batches before it progresses too far
or gets out of hand.
If rope does not become apparent in any of these “test”
loaves, it has practically no chance of developing during the one or two days’
storage in the home of the customer.
PRECAUTION MEASURES AGAINST ROPE
A. USE OF VINEGAR
The rope organisms even when present will not thrive
or develop “rope” in the finished loaf if there is sufficient acidity in the
dough. Hence, in the summer time, the addition of one pint of 90 grain vinegar
to each barrel batch of dough is a precaution well worth while especially in
shops where there is a tendency toward the development of rope.
If the vinegar is purchased locally, it is advisable
to ascertain its strength. The ordinary commercial vinegar sold is usually
about “40 grain” in strength. If such vinegar is employed as a preventive
against rope, a little more than one quart should be used in every dough
containing one barrel of flour. The amount of vinegar used of course, should
displace an equivalent quantity of the water ordinarily employed in the dough.
Incidentally, one quart of vinegar weighs
approximately two pounds. Thus, if one quart of vinegar is added to a certain
dough formula calling for 1 barrel of flour and 120 pounds of water, the amount
of water employed with this vinegar should be accordingly reduced to 118
The vinegar is added to the dough batch by merely
first stirring it into the bulk of the water, thus forming a very dilute
solution of vinegar.
To be more specific, the following procedure of mixing
should be adhered to:—
- Dissolve salt in a small portion of the total water.
- Dissolve yeast in another small portion of the total
- If dried milk is used, it should be dissolved in the
proper manner in another portion of the water.
- Stir the vinegar to be used in the remainder of the
- Add the salt solution to the water containing the
vinegar and next add the sugar, milk and malt. Mix these together for a few
turns of the mixing arms of the mixer.
- Start to draw the flour into the mixer.
- When the flour is about half drawn in, add the yeast
- After the yeast has been incorporated, add the
- Then finish mixing.
The use of vinegar as a precaution against rope will
in no way impair any of the qualities of the finished loaf and affords a very
easy and effective insurance against the development of rope. It is preferable
to use white distilled vinegar for this purpose.
B. GENERAL CLEANLINESS
While it is not true that rope only occurs in bakeries
which are not kept clean, it is, nevertheless, a fact that tiny particles of
old dough in cracks in the floor, wall, machines or pans offer an excellent
opportunity for the rope organisms to thrive and multiply. Naturally, where
conditions of this sort exist, the doughs are more likely to become infected
than where the bakery and all equipment are kept scrupulously clean.
A bakery is not necessarily actually clean because it
merely appears to be so to the casual observer. Care should be taken daily to
remove all remote traces of dust, dough, grease, flour, crumbs, etc., from the
walls, floors and all equipment, through the use of ordinary cleansing agents.
Otherwise, the dust arising from such particles of waste material is apt to
carry and distribute rope infection throughout the bakery.
C. REMOVAL OF STALE BREAD
Stale bread or other baked goods should not be allowed
to accumulate in the bakery, inasmuch as they furnish an ideal breeding place
for rope organisms with the attendant danger of spreading.
D. STORAGE CONDITIONS FOR RAW MATERIALS
While the flour or any one other raw material is not
necessarily the direct source of rope infection,—it must be kept in mind that
these organisms are likely to find their way into such materials and will
thrive if proper storage conditions are not adhered to. Cleanliness, proper
ventilation, sunlight, and cool temperatures are inhibitive to the development
of the rope organisms, whereas, dampness, warmth, the accumulation of dirt and
poor ventilation encourages the growth of these organisms.
E. DOUGH TEMPERATURE
Warm dough temperatures are more conducive to the
development of the rope organism than cooler dough temperatures. This is one of
the many reasons for the maintenance of relatively low dough temperature.
F. HEALTHY VIGOROUS PANARY FERMENTATION
The maintenance of
a vigorous healthy fermentation and conditioning of the dough batch by the use
of liberal amounts of yeast, assists in creating the desired gradual increase
in acidity throughout the dough, thus aiding in the prevention of the growth of
the rope organisms.
Moisture is one of the factors which encourages the
growth of the rope organism. Hence, a condition of ropiness is more likely to
develop in an underbaked loaf than in one which has been thoroughly baked out.
From this standpoint alone, it is important to avoid
flash heat in the oven which results in the crust forming too quickly. Such a
condition necessitates the removal of the bread from the oven before the
interior is properly baked and the excessive moisture remaining in the crumb,
especially in the summer time, often results in the appearance of rope where it
might not otherwise occur.
H. COOLING AND WRAPPING OF BREAD
Bread which is not thoroughly cooled before wrapping
is more susceptible to the development of rope than a loaf which has been
adequately cooled. Hence, it is always advisable to cool the bread after
baking, gradually,—although as rapidly as possible to a point where the
interior of the loaf is about 90 degrees F. before wrapping. Electric fans can
be used to good advantage in cooling the bread.
I. STORAGE OF BREAD
Bakery products of course, should be marketed as
quickly as possible after baking. However, if bread or other baked goods are
packed in baskets, crates, boxes or other containers a few hours before
delivery or kept in them after delivery, extreme care should be taken to keep
such containers as well as all delivery vehicles scrupulously clean and to
avoid holding the bread under warm or humid conditions.
STEPS TO BE TAKEN WHEN ROPE APPEARS
A. EXERCISE ALL PRECAUTIONARY MEASURES
If all of the precautions taken to prevent the
occurrence of rope described in the preceding paragraphs are conscientiously
followed out,—there is very little chance of rope developing in the resulting
bread. However, if in any case, ropiness does become apparent, all of the
precautionary measures should be immediately put into practice together with
the . modifications and more drastic steps which are described in the following
B. CHANGES IN DOUGH BATCH,—CONDITIONING,—BAKING AND BREAD COOLING
1. Vinegar in Doughs
While the use of vinegar in the dough batch has been
previously described as a preventive of rope,—the amount specified should be
doubled in any case where rope has actually been observed. In other words, one
quart of 90 grain vinegar or about 2 1/2 quarts of 40 grain vinegar should be
used in every barrel batch of dough made up.
2. Stiffer Doughs
When rope has made its appearance it is advisable to
set the dough a little stiffer than usual, by using slightly less water in the
dough than formerly.
3 Reduction in Sugar
The sugar content of the dough should be slightly reduced,
or better still—the sugar used should be replaced by a high grade malt extract
which contains a small amount of lactic acid.
4. More Age on Doughs
In shops where a condition of rope has been observed,
the doughs should be allowed to age a little longer than usual, inasmuch as the
additional acidity created thereby will assist in retarding the development of
the rope organisms.
5. Baking Conditions
The bread should be baked out just as far as possible
without impairing its softness or other qualities. Usually a slightly cooler
oven and a longer baking period will assist toward this end.
6. Cooling and Wrapping
While the rapid and complete cooling of bread prior
to wrapping has been discussed as a preventive measure against rope, it is
especially important that this point be heeded more strictly than ever, if rope
has already appeared.
C. METHODS OF ELIMINATING ROPE INFECTION THROUGHOUT THE
Just as soon as ropiness has made its appearance in
bread, it is necessary to take immediate steps to clean every part of the
bakery and all equipment by use of solutions such as vinegar which will be
effective in killing or retarding the growth of the rope bacillus. There are
several very effective ways of doing this which may be employed jointly or
separately, Some methods which have proved successful for this purpose are
described as follows:—
1. Live Steam—Treatment of Shop and Equipment
Live steam may be used as a means of cleaning the
shop, floors, pans and all general equipment coming in contact with the dough.
This live steam should be under pressure and delivered by means of a steam
hose. When employed, this steam should be applied to every article being
treated for several minutes. The nozzle of the steam hose should be held close
to each piece of equipment so as to insure close contact with the hot steam.
Steam at 100 lbs. pressure is very hot, namely 338 degrees F. In cases where
steam is used, % is important to avoid using steam at a lower pressure because
it will not be as hot and consequently not as effective in killing the rope
organism. As a matter of fact, steam at only 5 or 10 lbs. pressure lacks force
and is not much hotter than the temperature of the interior of the loaf in the
ordinary baking process. Such steam therefore, is not hot enough to destroy the
2. Formaldehyde Treatment
An effective means of sterilizing the bakery and
killing rope infection is through the use of formaldehyde. In severe cases of
rope, this treatment is especially advisable, and may be divided in four parts
(a) WASHING OF FLOORS WITH FORMALDEHYDE SOLUTION
This should be carried out while there is no work going on
in the shop. First secure commercial liquid formaldehyde of standard strength
(40 % U. S. P.). Mix one part of this with twenty parts of hot water.
Scrub the floors of the bakery with this dilute solution, getting it well into
all corners and crevices. While the formaldehyde fumes will not injure the
machinery, this solution should not be applied to the troughs or other
equipment and should not come in contact with any materials. After washing the
floors with formaldehyde thoroughly wash the same with hot water.
(b) FUMIGATING WITH FORMALDEHYDE
Fumigating with formaldehyde is best done overnight.
Saturday is generally most convenient. Where rope is not too severe, it usually
can be checked for a few days by adhering to the instructions previously
stated,—until there is no work going on in the shop and then the fumigation
can take place. In order to fumigate the bakery with
formaldehyde proceed as follows:—
- Close the place up tight.
- Burn three large sized formaldehyde candles free from
sulphur for every 100 square feet of floor space.
- After fumigating, be sure to “air” the shop thoroughly.
- Do not permit formaldehyde fumes to come in contact
tvith flour or other ingredients.
VII. INVESTIGATION OF SOURCE OF ROPE IN
A. EXAMINATION OF MATERIAL
By closely observing the necessary preventive and
curative measures for rope as described in the foregoing paragraphs, it is
extremely doubtful that any case of rope will get the best of the baker.
Even though these measures do result in eliminating
rope after it has once appeared, it is very important to carefully examine the
raw materials and general shop conditions in order to locate the exact cause of
the rope infection and to eliminate the same so as to prevent any recurrence of
If any particular material is suspected to be the
cause, it is well to set this aside from all other materials and to conduct the
trial baking test in order to ascertain whether or not this suspicion can be
B. BAKING TEST METHOD
In order to make clear the method of conducting this
test, let us assume that the baker wishes to test out one or specific
ingredient which may be under suspicion.
The procedure in conducting these baking tests are
described in the following paragraphs.
C. GENERAL PRELIMINARY PROCEDURE
- Select some room outside of the part of the bakery
where the commercial doughs are handled, which will be suitable for the making
up of small test doughs by hand.
- Thoroughly clean, fumigate and then ventilate’ the
- Select the utensils necessary for the making up of two
trial doughs, each of which should be large enough to produce about six loaves.
- Thoroughly clean and sterilize all utensils to be
used. This can be done by cleaning them and by thorough heating in the oven.
- The baker handling these utensils should wash his
hands in a disinfectant solution before starting in. His uniform
should also be freshly laundered and clean.
D. “CHECK” DOUGH With the exception of the particular ingredient
to be tested, all the
materials necessary for the work should be taken from
the bakery into the room where the trial baking tests are to be made.
Then a new sample of the particular ingredient under
investigation should be secured from some source outside of the bakery. Care
should be taken to make sure that the sample selected will not cause rope in
bread. One dough large enough to produce several loaves should be made up using
this ingredient. This dough should not contain any vinegar and should be moderately
slack. It should be handled in the regular way. During the fermentation period
and while in the pan it should be covered with a clean sterilized cloth to
prevent infection. When placed in the oven the cloth should be removed and care
taken to avoid overbaking. After baking the loaf should be cooled, wrapped, and
placed in a cabinet where a fairly warm and humid condition is maintained. Thus
if rope is at all likely to develop, it will surely do so under these favorable
E. “TEST DOUGH”
Directly after making the first “check” dough as
described above, a sample of the ingredient to be tested should be brought into
the room from the bakery,—and a test dough made up using this ingredient
together with the other necessary materials taken from the same lot as those
used in the check dough.
The formula and shop conditions should be same as
those employed in the check dough and the same care should be exercised in
handling and baking the dough.
The baked loaf should be wrapped in the same manner
and placed under similar conditions of temperature and humidity.
F. EXAMINATION OF CHECK AND TEST LOAVES
After 24 hours, one loaf from each dough should be
examined and thereafter at intervals of 12 hours for about three days.
This examination may result in any one of three ways,
each of which are explained as follows:—
1. Both Sets of Loaves Exhibiting Ropiness
If the loaves from both the check dough and the test
dough develop rope, the indication is that some material other than the one
under investigation is the cause of the infection. This of course is only true
provided due precaution and care has been exercised in handling both doughs and
that the new sample of the ingredient being investigated and used in the
“check” dough has been previously proven not to develop a ropy loaf.
In such a case where the evidence secured indicates
that some ingredient other than the one being investigated is the carrier of
the rope infection, each ingredient used should be tested in the same manner by
means of further baking tests.
2. None of the Loaves Exhibiting Ropiness
In case none of the loaves from either set of doughs
it is quite apparent that the development of rope in
the bakery can not be attributed to the particular ingredient in question or
any of the other ingredients used. In this event, it would appear that some
other source of infection existed in the shop which probably has been removed
by the necessary cleaning and disinfecting measures taken.
3. The Case of the Development of Rope Only in the Test
If the “check” loaves are free from rope but it is
observed that ropi-ness develops in any of the “test” loaves, the indication is
that the particular ingredient being tested and used in the “test” dough was at
fault. This ingredient should be promptly removed from the storage room and not
used until further investigated. However, no definite conclusion should be
drawn until the baking test has been repeated with similar results, and then
confirmed by bacteriological tests conducted under the supervision of a man who
has been trained in this scientific line of work.
G. IMPORTANCE OF CONFIRMATION OF BAKING TESTS BY
If the baking tests described above indicate that any
one particular raw material is the cause of rope, this one ingredient should be
removed from contact with the other materials and not used. However, before
being sure of this indication, actual bacteriological tests are necessary.
VIII. MOLD DEFINED AND EXPLAINED
The word “mold” refers to a certain group or class of tiny
plants which are visible to the naked eye and which are made up largely of a
cottony, thread-like structure which presents a “furry” appearance. Molds are
unquestionably familiar to practically everyone, inasmuch as nearly all
household foods, if kept for a period of time under warm or moist conditions
will exhibit mold growth. There are various types of molds,—differing somewhat
in general appearance, color and rapidity of growth.
The color of these molds is usually brown, red, orange,
yellow, green, blue, pink, white or black. While the majority of the common
molds are not poisonous, a few of them are said to be detrimental to health.
IX. THE GROWTH AND DISTRIBUTION OF MOLDS
As the mold plant grows and develops on food or other
organic matter, little thread-like stalks or “whiskers” become noticeable. A
tiny ball usually develops on the top of these stalks and is often spoken of as
the spore sack. This sack contains hundreds of tiny mold seedlings or spores
each of which is so small that it can only be seen through the microscope. On
the slightest disturbance such as a mild breeze, these spore sacks
break,—releasing numberless mold spores which float away in the air as tiny
specks. Naturally, under ordinary conditions some of these spores find a
lodging place on bread or other foods exposed to the atmosphere. Furthermore,
mold spores can be carried from one place to another by flies or other insects.
Under proper conditions of food, warmth and humidity these
spores will thrive and produce a luxuriant growth of mold plants and thus the
process of reproduction and distribution of mold continues. Mold spores usually
settle on the outside of the bread or other foods and therefore, mold growth
first appears on the exterior surface. Then the thread-like projections of the
mold plant extend themselves into cracks or tiny openings on the surface and
thus the mold spreads from the exterior to the interior of the loaf. The
subject of mold in relation to bakery products should be of interest to every
baker and should be given serious consideration inasmuch as a loaf of bread
which becomes moldy prior to delivery or very shortly thereafter, frequently
proves disastrous to the sale of that particular loaf.
In this connection, it should be remembered that there are
certain conditions which pre-dispose and encourage the development of mold in
bread and other bakery products. On the other hand, certain sanitary
precautions may be taken which will aid materially in delaying or preventing
the development of mold and if these precautions are conscientiously adhered
to, it will be rare that the baker will be confronted with the mold problem.
X. PROTECTIVE MEASURES AGAINST MOLD>
A. GENERAL CLEANLINESS
While some mold spores are floating about in
practically all ordinary atmosphere, the presence of stale bread,—crumbs, old
waste dough 01 other similar material in or near the bakery as well as unclean
machinery, wrapping paper, bread boxes, wagons or cases offer ideal conditions
for the rapid development of mold plants from which numberless mold spores are
These mold spores then contaminate the atmosphere in
the neighborhood of the moldy material and this mold laden air circulates
throughout the immediate vicinity. In this way such products as bread coming in
contact with this air are naturally infected with a greater number of mold
spores than ordinarily and under these conditions there is a much greater
likelihood of the subsequent appearance of mold in products thus exposed and
Therefore, one of the first preventive measures
against mold is the maintenance of absolute cleanliness throughout the bakery,
including machinery, equipment, wrappers, bread boxes, delivery wagons, etc.,
as well as all bakery premises. This of course, means frequent scrubbing of the
bakery and thorough cleaning of all machinery and equipment coming in contact
with the bread or other baked goods. Furthermore, no stale bread or rubbish
should be allowed to accumulate in the bakery or in the immediate neighborhood.
Molds thrive best in dark places. Hence it is
important that the bakery be amply supplied with sunlight and well ventilated.
B. BAKING, COOLING AND WRAPPING OF BREAD
As a preventive against the development of mold in
bread; it is essential that the loaf be completely baked, having a crust which
is not unduly moist.
The loaf should be thoroughly cooled and the crust
surface dry before wrapping. If bread is wrapped while still warm, it will be
in an ideal condition for the rapid development and growth of any mold spores.
Furthermore, the wrapping paper used should be stored in a dry, clean, cool
place and kept absolutely protected from dust. Bread boxes or cases should be
kept scrupulously clean and properly ventilated for if they are not, some of
the moisture escaping from the loaf may condense on the surface causing a moist
or humid condition which encourages the growth and development of molds.
C. FILTERED AND WASHED AIR IN THE BAKERY
The installation of air filters and air washing
equipment whereby the air entering the bakery is first cleaned, aids
considerably in eliminating the dust particles which carry mold spores in the
air. Such a system serves as a preventive measure against the development of
mold in bread by cutting down materially the number of mold spores floating
about in the air of the bakery and in this way the chances of the subsequent
occurrence of moldy bread is greatly reduced.
The infection of bread and other bakery products with
mold spores takes place after the product is baked; namely, during the cooling,
wrapping, handling, delivery or storage. While it is impossible for the baker
to control the conditions under which the bread is handled after delivery to
the customer, it is quite certain that if the proper protective measures
against mold are taken in the bakery, there will be very little likelihood of
complaint on the part of the housewife concerning moldy bread.
IN BREAD CANNOT BE CAUSED BY THE INGREDIENTS USED
Many tests have been conducted which demonstrate that the
development of mold in bread cannot be traced to any of the ingredients used.
This is due to the fact that the temperature reached by the dough in the baking
process is sufficiently high to kill any mold spores which might be present in
the dough, and the loaf directly after baking is thereby rendered sterile
insofar as mold is concerned.