Bio Class 11 Bread Mold Experiment

BIOLOGY EXPERIMENT

AIM:To study suitable conditions for bread mould growth.

ACKNOWLEDGEMENTI would like to thank our bio teacher Ms Hema malini ma’am for giving us an opportunity to do such an interesting experiment and also for spending her invaluable time helping us conduct our experiment. I would like to thank my parents who have stood by me and helped me complete the experiment.

What is Mold?

Mold is something that we often take for granted, as something that makes us have to throw the bread away or the cheese smell bad.

Mold is, in fact, a fascinating organism which has had many different uses over the years and our lives would not be the same without it.

A mold or mould) is a fungus that grows in the form of multicellular filaments called hyphae.In contrast, fungi that can adopt a single celled growth habit are called yeasts.

The scientific name of bread mould is Rhizopus stolonifera

Molds are a large and taxonomically diverse number of fungal species where the growth of hyphae results in discoloration and a fuzzy appearance, especially on food. The network of these tubular branching hyphae, called a mycelium, is considered a single organism. The hyphae are generally transparent, so the mycelium appears like very fine, fluffy white threads over the surface. Cross-walls (septa) may delimit connected compartments along the hyphae, each containing one or multiple, genetically identical nuclei. The dusty texture of many molds is caused by profuse production of asexual spores (conidia) formed by differentiation at the ends of hyphae. The mode of formation and shape of these spores is traditionally used to classify molds.[4] Many of these spores are colored, making the fungus much more obvious to the human eye at this stage in its life-cycle.

Molds are considered to be microbes and do not form a specific taxonomic or phylogenetic grouping, but can be found in the

divisions Zygomycota and Ascomycota. In the past, most molds were classified within the Deuteromycota.

Most of us know that food seems to become moldy more quickly in the summer than in the winter when it is colder. Food in refrigerators seems to keep longer than food left out in the sun. Is this true? Does temperature really affect the rate at which mold grows?

Important Note

Please note that some people are allergic to mold; ask your doctor or parents. If this is the case, do not pick the Mold Bread Experiment. Always wear gloves and a mask, wash your hands, and don’t eat or drink whilst you are performing this study.

Performing the Mold Bread Experiment

Hypothesis

In the Mold Bread Experiment we are trying to prove that;

"Mold grows quicker at higher temperatures."

What You Need for the Mold Bread

Experiment

•5 slices of bread. Any sort will do but it is perfectly fine to use

cheap white sliced bread as then you will know that all of the

slices are a similar size, weight and thickness. You must

make a note of the brand and use-by date so that anybody

else wanting to repeat the Mold Bread Experiment can use

the same type.

• 5 boxes to keep the bread

in

• Clean knife

•Chopping board

•Sticky labels

• Mold Spores -. There are mold spores all around us in the air

which will eventually grow on the bread .

• Mask

•Gloves

•Agar -agar

Method

•Using the sticky labels and

the marker pen label the

different boxes .

•Cut each slice into two so that one con be wet while the other

dry.

•Put the paired slices of bread into each box and seal the box

tightly.

Agar plates

•Put the 1’ box into the freezer, the 1 boxes into the

refrigerator ,1boxes somewhere safe in a warm room,1 box

ouside in the sun and the last one ouside in the shade.

Because the boxes in the freezer and fridge will not be getting

much light .so light is a factor here.

•Every 24 hours, preferably at exactly the same time every day

moisten the wet slice and observe if there is any growth

•You should repeat these counting processes for 10 days .

•Keep a careful note of your results for each slice of bread for

the entire duration of the experiment

•The mold can then be transferred to the agar plate for faster

growth.

•Once you have finished, throw out all of the boxes without

opening them.

OBSERVATION TABLE

SL.N

O

LOCATION OF

BREAD

WETNESS/

DRYNESS

TIME TAKEN FOR

MOLD TO GROW

1. Outside Wet

Dry

10 Days

14 Days

2. Outside in the

shade

Wet

Dry

7 Days

13 Days

3. Inside a warm Wet 8 Days

room Dry No growth

yet

4. Inside freezer Wet

Dry

No growth yet

No growth yet

5. Inside

refrigerator

Wet

Dry

No growth yet

No growth yet

Chart for comparison b/w location,moisture

and days taken for mold growth

Outside in light Outside in shade Inside warm room cold temp.0

5

10

15

20

25

WetDry

Before After

NO CHANGE IN THE ONES KEPT IN THE FREEZER AND

REFRIGERATOR

The breads above are dry while the ones

below the dry ones are the wet ones.

But there was a change in those kept in

the shade:

The wet slice had growth of mold but not

the dry slices .Why?

INFERANCE

1.The slices in the shade had faster bread mold

growth than the ones in the sunlight.

2.The slices which were in a warmer

temperature had more mold growth than the

ones in the colder temperatures.

3.The slices which had moisture had more mold

growth than the drier ones.

4.So. The factors effecting bread mold growth

are:

a.light – lesser the light more the

growth

b.moisture – more the moisture more

the

growth

c.temperature – more the

temperature

better the

growth

Why are the Results Important?

The food industry spends millions of dollars every year on refrigeration and it is very important that we use this knowledge for preventing food spoilage.By preventing food spoilage thee will be enough food for all.

Facts About Mold

Common molds[

Acremonium Alternaria Aspergillus Cladosporium Fusarium Mucor Penicillium Rhizopus Stachybotrys Trichoderma

•Mold is not a plant but a fungus like mushrooms and

toadstools. It grows on food and other organic matter,

breaking it down into slime and extracting nutrients for

growth.

•Alexander Fleming discovered that a common type of mold

fungi kills germs. From this, he made a medicine called

penicillin which has saved millions of lives over the last 80

years. Many other life-saving drugs are made from chemicals

obtained from mold.

•Mold is one of nature’s cleaners. It breaks down dead organic

material and recycles the nutrients back into the soil. It is

essential in nearly every ecosystem in the world.

•We use molds for flavor in some foods such as blue cheese,

soy sauce and Quorn(TM).

• Molds cause biodegradation of natural materials, which can be

unwanted when it becomes food spoilage or damage to

property. They also play important roles in biotechnology and

food science in the production of various foods, beverages,

antibiotics, pharmaceuticals and enzymes. Some diseases of

animals and humans can be caused by certain molds:

disease may result from allergic sensitivity to mold spores,

from growth of pathogenic molds within the body, or from the

effects of ingested or inhaled toxic compounds (mycotoxins)

produced by molds.

BIBLIOGRAPHY:

1. www.health.state.mn.us/divs/eh/indoorair/mold/ 2. www.madsci.org/posts/archives/1997-

05/863449273.Mi.r.html3. www.fsec.ucf.edu 4. www.wiki.org 5. HTTPS://EXPLORABLE.COM/ MOLD - BREAD -EXPERIMENT

THANK YOU

DONE BY:

NIKHIL.M

RAHUL.A