INT1 Task 3

Does the Cold Stop Bread Mold?By James Thompson

Project Plan Design

Bread mold fungus is the most common fungi in the world. Molds occur commonly on bread due to the desirable source of nutrients for the mold. In tandem with the nutrients, bread is typically kept in warm and moist places where mold can thrive. (Mold 2015) Typically mold spores tend to become active at temperatures between 70 – 90 degrees Fahrenheit. However, the spores become dormant when introduced to temperatures below 32 degrees Fahrenheit. (Wold & Reeves 2015).

Literature ReviewThere are many different ways to see how mold spores thrive. Since it is such a common type of mold, there have been many experiments done on bread mold.

Aldo-Rafael Cos carried out an experiment on four types of bread, each sealed in a Tupperware container and moistened with a few drops of water. Each container was kept at room temperature with an adequate source of light. The bread was observed for two weeks, with photographs of the progression of mold being taken. The bread developed mold, though some slices developed mold spots faster than others. (Cos 2005)

Sylvia Cini took a different approach to her experiment. While she followed the steps of the experiment above, she took it a step further. She placed her containers in different temperatures and varying degrees of humidity. Recording the results of her experiment. (Cini, 2015)

For this experiment, for ten days, each sample will be put into varying degrees of temperature, moisture, and light. At the end of ten days the samples will be collected, photographed and measured.

Experiment Design Steps

1. Clean and sterilize four Tupperware bowls. (Hand wash and 1 dishwasher cycle with steam heat).

2. Make labels for Tupperware lids. (Sample and Temp should be noted on the labels).3. Select four pieces of white bread. (Store bought).4. Check bowls, make certain they are clean and dry.5. Place the bread in the Tupperware bowls. (One slice to each bowl)6. Prepare Sample B with a few droplets of water.7. Place labels on lids:

a. One labeled “Warm and Dry” (Control)b. One labeled “Warm Dark and Dry” (Sample A) c. One labeled “Warm and Moist” (Sample B)d. One labeled “Cool and dry” (Sample C)

8. Seal samples.

ReasoningTo adequately test each environment for their ability to excite or render mold spores dormant, the experiment needed to have multiple samples in varying degrees of temperature and light. It also required a sturdy container to protect the validity of the sample.

Sequence of Events

The amount of mold grown on the samples is dependent on the temperature of the environment they are placed in and any moisture present.

1. All temperatures in temperature control areas have been confirmed by use of the thermometer.

2. Samples are then placed in the temperature controlled areas:a. Control 70 Degrees Fahrenheitb. Sample A 80 Degrees Fahrenheitc. Sample B 70 Degrees Fahrenheitd. Sample C 30 Degrees Fahrenheit

3. Samples are checked every day, for ten days, at the same time each day.4. At the end of ten days, the samples are collected, measured and photographed.5. All samples will be properly disposed in a sealed plastic bag.6. Containers will be thoroughly cleaned. If unable to clean, they will be disposed of.

Tools and Technologies

Kitchen DishwasherWhite Duct Tape (Labels)Sharpie4 Tupperware containers4 slices white breadKitchen thermometer (Degrees Fahrenheit)Refrigerator (Set to 30 Degrees Fahrenheit)Kitchen (Consistent temp. 70 Degrees Fahrenheit)Water heater room (Consistent temp 80 Degrees Fahrenheit)Iphone 5c cameraMicrosoft Office Publisher

Variables

Independent variable: The Temperature the samples were exposed to during the experiment, the amount of light each sample received.Dependent variable: The amount of mold grown on each sample after a ten day period of observationControlled variable: The type of bread used, the size of the bread in the sample, the size of the containers they were placed in, time the bread was checked everyday.

Threat to Internal ValidityBy ensuring all of the Tupperware containers were thoroughly cleaned, sterilized and dried. The experiment assures that no outside contaminants will interfere with the integrity of the samples or the results. By ensuring all environments maintain a consistent temperature for the duration. Labeling and sealing all containers before the experiment began.

HypothesisThe Hypothesis of this experiment is that bread mold will lie dormant in temperatures below 32 degrees and thrive in warmer temperatures. This hypothesis was based off of a statement made on the Mold Blogger website.

Process of Data Collection

As predicted, mold spores are dormant in cooler temperatures. The samples in the warmer temperatures experienced prodigious mold growth, while the sample in cooler temperatures experienced little to no growth.

This is the Control Sample. Note the light coloration of the mold and its spread into the crust of the bread.

This is Sample A “Warm, Dry and Dark”. 80 Degrees. Note the nearly complete consumption of the bread by the mold, and the growth of the white mold on top of the green. This was the most remarkable growth in the experiment.

This is Sample B “Warm and Dry” 70 Degrees. Note the difference between Sample B and the Control Sample, both kept at the same temperature. This bread was slightly moistened, very little mold is growing on the crust.

This is Sample C “Cool and Dry” 30 Degrees. In contrast to the other samples in the experiment, note the small amount of mold on this sample. It would appear that while the mold spores are dormant in cooler temperatures, they do exhibit a small amount of activity.

Appropriate MethodsWhen samples were collected and photographed, the data was entered into Microsoft Publisher and a grid was imposed over each sample. The grid was to calculate the square centimeters of the mold grown on each sample. The amount of mold grown on the samples in ten days seems a good amount of time to let mold spores gather together. A longer time might be necessary, though, to see if mold spores would remain as dormant as they were in cooler temperatures, or if they would continue to grow.

(Meta 2015)

The Above chart shows a difference of two cm² between the Control Sample and Sample B, and a large difference of 37 cm² between Sample A and Sample C. Providing an average of 36 cm² between samples.

Conclusion

Confirmation of HypothesisThe results shown above confirm that mold does lie dormant in cooler temperatures. While keeping other samples at varying temperatures produced mold growth, keeping one sample at a cooler temperature slowed the activity of the mold spores to a relative stand still. Only producing a 2 cm² spot on the sample kept cool, as compared to the average 36 cm² on the other samples.

Experimental Design as a Key FactorDesigning the experiment is like a road map for the experiment. If something happens within the experiment that was not in the original parameters, then one is able to check their map and see where the error is. Similarly, if no error occurs, the design can map out a way to replicate the successful experiment in the future

Replication

In order to replicate this experiment, it is important to use clean containers to store the bread in. Since any outside material might contaminate the ability for the mold to grow. Take into account that high humidity in certain regions might alter certain aspects of the experiment, causing certain molds to grow faster.

Evaluation of ValidityIf others were to use this experiment, it would help determine the validity of the steps used and the results gathered. Scientists replicate experiments to determine if the original experiment was successful. If the replication of the experiment is successful, the validity of the original experiment is strengthened and the validity made firmer. If the experiment is not successful, it provides a reason to reexamine the Experiment’s Design. To see if there is an unknown element at play that the scientist was previously unaware of.

Reference List

Mold (2015) Mold on Bread. Retrieved from: http://www.moldbacteriafacts.com/what-is-mold/mold-on-bread/

Wold & Reeves (2015) Mold Blogger: Fight Mold and Win.: 3 Things Mold Needs. Retrieved from:http://moldblogger.com/top-3-things-mold-needs-to-grow/

Cos (2005) Comparing the Rate of Mold Growth on Different Breads. Retrieved from:http://www.csun.edu/scied/2-longitudinal/long_research/

Cini (2015) Three Cool Science Experiments with Bread Mold. Retrieved from:http://www.brighthubeducation.com/science-fair-projects/107513-bread-mold-science-experiments/

Meta (2015) Bar graph built by the Author from test data at:https://www.meta-chart.com/bar