TESTING TO SEE IF THE CONDITION BREAD IS PLACED IN AFFECTS ITS
MOLDING RATE
Kate Hampton
Cary Academy
ABSTRACT
The purpose of the experiment was to see if the condition that Honey Wheat bread was placed in
affected the molding rate. It was hypothesized that the condition would affect the molding rate,
since the amount of mold spores different in each environment. Additionally, it was predicted
that the bread near the window would grow the most mold, since the sunlight contained the most
mold spores. In the first experiment, bread was placed in an aluminum pan in four different
atmospheres. For the second experiment bread was placed a Ziploc bag, also in the four different
environments and measured. Finally, in the last experiment, wet bread and dry bread were placed
in two separate jars and the amount of mold was observed. For the first experiment the average
weight went from 27.75 grams down to 19.95 g in a few days. Although the bread shrunk and
hardened; no mold was grown for the first or second experiments. The third experiment was the
only one in which the bread grew mold and it grew 7 cm of mold. This mold was a unique kind
that was a red-pinkish color.
INTRODUCTION
The purpose of the experiment was to test and see which environment keeps bread fresh the
longest. The bread will be placed in a variety of environments such as a dark room, open
window, regular lighting and lastly a refrigerator. The environment which keeps bread fresh
without molding would be considered as the best for this keeping bread fresh.
Mold is a fungus, which is not the same as a plant and animals. Fungi relies on others plants as
its food sources because it lacks chlorophyll; therefore making it impossible to produce their own
food. Mold comes in many colors and has many pros and cons. For example, another form of
fungus called yeast is a key ingredient in the bread we eat. Also, for bleu cheese the blue mold
that grows on it is what gave the cheese its name. These are the good aspects of mold, but there
are also many parts of mold that damage things. Mold can ruin food and make it impossible to
eat. Mold eats only organic material as they primarily degrade cellulose, often found on plants.
Bread Mold is not complex fungus, since it simply gets its food from things such as grains,
fruits, vegetables or flesh. Mold spores are tiny and usually remain suspended in air. As soon as
it finds the right environment for it to grow, the spores transform into the living fungus. A mold
becomes visible once a spore has germinated and it has grown and divided from one cells to
millions. At the tips of the hyphae, spores form sexually or asexually in reproductive structures.
Mold is attracted to bread because of the limited moisture and a great source of nutrition. This
provides a perfect resting place for molds to grow, thrive and reproduce. The main cause of this
is normally because of when one of the millions of mold spores meets bread. Varieties of sources
were consulted and most said that it all depending on the condition. Some say that a bread box
keeps bread fresh the longest. If bread has a higher moisture level, it has a better chance of
molding first.
Some things that were observed from the package were that the bread was best used by January
29, 2012. It was then configured that the due date was based off the regular time that the bread
would mold based off the average environment. The flavor or kind is Honey Wheat and this
certain type of bread has no artificial preservatives, colors or flavors. Another fact that was found
on the package is that this bread has no High Fructose Corn Syrup. According to the wrapping
this bread is low fat, Cholesterol Free and 0 grams of Trans Fat per slice. Some other things that
were noticed were that the color on the inner was golden with flakes of brown. The outside was
brown and on the inner layer it had little holes.
Some quantitative observations that were made were that the bread is about 60 square cm. This
was configured because squares of paper that was exactly one cubic centimeter in area were fit
into the area of the bread. The bread was also measured for weight. For four different slices of
bread, they weighed 28 g, 29 g, 28 g and 26 grams. The average was then calculated and it was
found that the bread is 27.75 grams on average.
It was hypothesized that the condition would affect the molding rate of bread. This was
hypothesized because it was found in the background research that molding rate was closely
related with the amount of moisture in the bread/environment. So an environment that allows a
lot of moisture will probably grow the most amount of mold the fastest. The sunlight most likely
contains the most amounts of mold spores. It was then predicted that the window with a lot of
sunlight would grow the most mold on the bread.
MATERIALS & METHOD
Figure 1; Nature's Own, Honey Wheat Bread

Honey Wheat Bread

Paper square centimeter

Aluminum pan

Ziploc Bag

Clear container

Tape

Microscope
Honey wheat bread was placed into four different atmospheres. The bread was first placed in a
room that is half lit, or regular lighting in an aluminum pan. The molding process was recorded,
by measuring the amount of mold with paper squared cm strips. Then the bread was placed near
a window with a lot of sunlight, or constant light beating down in an aluminum pan. Again, the
molding process was recorded and measured. Next, the bread was placed in a dark room with no
sunlight and the amount of mold was measured in an aluminum pan. Lastly, the bread was
refrigerated in the aluminum pan and measured. The molding rate in each atmosphere was
observed and compared.
The independent variable, or the part of the experiment that is changing, is the atmosphere bread
is placed in. The dependent variable, or what is being measured, is the amount of mold grown on
the bread. Lastly, the control is the bread in a half-lit environment, since that is usually the
location of bread. There are three safety concerns involved with this experiment, the first is to
not breathe in near the bread, then don’t touch the mold and finally don’t eat the bread.
Honey wheat bread was placed into 4 different atmospheres in Ziploc bags. The bread was first
placed in a room that is half lit, or regular lighting in the bag. The molding process was recorded,
by measuring the amount of mold with paper squared cm strips. Then the bread was placed near
a window with a lot of sunlight, or constant light beating down in the bag. Again, the molding
process was recorded and measured. Next, the bread was placed in a dark room with no sunlight
and the amount of mold was measured in a Ziploc bag. Lastly, the bread was refrigerated in the
bag and measured. The molding rate in each atmosphere was observed and compared.
The independent variable, or the part of the experiment that is changing, is the atmosphere bread
is placed in. The dependent variable, or what is being measured, is the amount of mold grown on
the bread. Lastly, the control is the bread in a half-lit environment, since that is usually the
location of bread.
Honey Wheat bread is cut into 2.5 cm pieces. The bread is then placed in 2 clear containers with
a lid. Tape is wrapped around the container. In one container the bread is just placed in the jar.
The other container has bread that was dipped into water then placed in the jar. The molding
process will be observed with 1 square cm strips.
The independent variable is the water in the jar. The dependent variable is how much mold
grows. The control is the amount of mold growing in the jar without the wet bread.
RESULTS & DISCUSSION
In the first experiment conducted, as a result of the lack of mold; the weight was measured and
recorded. Originally the bread weighed at an average of 27.75 grams. After the bread was
exposed to their designated environments for a few days, the average became 19.95 grams.
When the bread was first measured four slices measured, 28 g, 29 g, 26 g and 28 g. Then
afterwards the weight of the two breads was recorded and average. For the dark room, the two
slices weighed 19.9 g and 20.2 g; making the average 20.55 g. The two slices that were
refrigerated weighed 19.5 g and 20.1 g, averaging at 19.8 g. In the half-lit environment the
average was 19.65 g and the window 19.8 g. It was observed that the bread was hard and
considerably shrunken. There was no mold found on this bread. For the second experiment
performed there was no mold recorded and the hardness of the bread didn’t seem to change.
Average Weight (g)
20.8
20.6
20.4
20.2
20
19.8
19.6
19.4
19.2
Window
Half-Lit
Fridge
Type of Atmosphere
Figure 2; Bread after a few days in atmosphere
Dark Room
35
30
Weight(g)
25
20
1
4
15
10
5
0
0
1
2
3
4
5
Figure 3; Original weight compared to after a few days
In the third experiment, mold finally grew on the bread. After four days, in the wet bread jar, 3
cm of mold had grown. Overnight, 4 more centimeters of mold grew, leaving the bread with 7
cm of mold. When the bread was observed, it was found to be pinkish-red. Usually, a greenish
blue is expected to grow on the bread, so this was a unique mold. The bread was examined under
a microscope and showed quite interesting results. The mold had not completely taken over all of
the bread. It was found that there was still some bread left, in which the mold had to grow upon.
It is safe to assume, that if the bread had been left out for a few more days, the mold would have
developed and continue to feed off the breads nutrients.
Figure 4; Bread in a jar
Figure 5; Bread after 4 days in sunlight jar
Figure 6; Red-Pink Molded Bread
Figure 7; Birdseye View of mold
CONCLUSIONS
For the first experiment conducted, the hypothesis was partly confirmed and partly wrong. As a
result of no mold, it was unclear whether or not sunlight’s molding rate was the fastest. The
bread did shrink in all locations because the bread lost its moisture. But, due to the lack of mold,
the experiment was unable to determine which environment grew mold the fastest. It was
determined though that the bread in the dark room shrunk the least, which was inferred a result
of the environmental differences. If the bread might’ve had more contact with mold spores in the
air or in water, the chances of mold would have been greatly raised.
The experiment was decided to have been a failure, but that didn’t mean info was learned from
this experiment. From the experiment learned was that bread needs more contact with mold
spores to grow. Usually, bread is taken out of the bag and closed back up. That is generally
where the spores and bread meet. But, since the bread had been just taken out of the bag and
placed in their environments, the mold spores and bread never came into contact. The same
problem occurred with the second experiment, especially since the bread had gone into a sterile
Ziploc bag. The third experiment was interesting. When the bread was soaked in water, the
spores and the bread had their chance to meet. No mold was grown on the dry jar, for the same
reasons as the earlier experiments.
In the third experiment, there were found to be a couple ways to improve the experiment. Instead
of just doing a wet jar and a dry jar, more jars with differing amounts of water would be added.
In one jar, you could have a pool of water, semi-damp and the last one dry. The molding rate
could then be observed.
Future experiments to be conducted would be if there were different types of bread placed in the
same atmosphere, with the molding process observed. After performing this experiment, it would
be easy to determine what type of bread lasts the longest without molding. This might help
people determine what bread to buy, since they will know what bread lasts the longest for use.
From the third experiment, it was mentioned earlier how the bread had developed a red-pink hue.
This was a unique and rare type of mold. Generally, this type of mold is found around showers
and sinks. It was then inferred that the damp bread brought out the mold that is usually seen with
damp atmospheres. This is not usually found on bread because bread is not dunked in water.
REFERENCES
"Growing Bread Mold." Science Fair Adventure.com. Science Fair Adventure.com, 2007. Web.
January 9, 2011
Johnson, George B. Biology, Principles and Explorations. Austin TX; Holt, Rinehart and
Winston, 1996. Print
Madison Rabe. "Which type of bread grows mold the fastest?" Answers. Com. Answers
Corporation, 2012. Web. January 9 2011
McGrath, Kimberly A. “World of Biology.” Detroit Gale Group, 1999. Print.
Savan12986. "Where do you store bread to keep it fresh longest?" Answers.com. Answers
Corporation,2012. Web. January 9, 2012.
Squirrel Man. "What bread lasts the longest without molding?" Answers.com. Wiki Answers,
1994. Web. January 9 2012.