Our hypothesis is that the darkness is the best lighting condition for keeping bread out. This is because darkness can create a cool and dry place for bread to stop mold growth and staling.

We will research what mold is and why some people don't leave their bread in the refrigerator.

What is Mold?

• Mold is a fungus that forms and spreads on a variety of damp or decaying matter
• There are over one hundred thousand species of mold
• When tiny mold spores land on moist surfaces, mold starts to grow
• Mold needs warmth, moisture and nutrients to grow
• Foods like bread have mold inhibitors to stop mold growth

Why do some people not leave their bread in the refrigerator?:

Wheat flour in bread and many grains of starch. The normal state of starch is an a crystalline which means it has a defined shape. Once baked, the shape starts to break down and become amorphous ( meaning it has no defined shape). Once cooled, the slow process (retrogradation) in which it turns back into is crystal shape (recrystallization) makes the bread harden and stale. Putting bread in the refrigerator can speed up the cooling process.

Controlled variables:

• The duration of the experiment (3 weeks)
• Type of bread
• Temperature

Manipulated variable:

• The lighting condition

Responding variable:

• The lighting condition best for keeping bread out

Procdure

1. Put on gloves
2. Put three breads into three clean zip loc bags
3. Put one bag in a dark place like a box
4. Put one bag under a lamp for constant light
5. Put one bread beside a window so it gets sunlight and darkness

Week 1: The breads were mostly the same. The breads that got sunlight and darkness started to get a little bit hard

Week 2: The breads beside the window became stale. They started growing very tiny spots.

Week 3: The breads beside the window were stale and grew spots. The rest of the breads stayed the same although the crust came of a little bit.

Analysis

We observed that in the duration of the experiment, it took the bread about 1-2 weeks to start to stale and mold. This shows that even leaving your bread out for a couple of days can make it stale. We noticed that our molds were different colors. This is necessary to know because this shows how many types of mold there are and how different circumstances can change the size color.

Conclusion

To conclude, we failed to reject nor support our hypothesis. Although we were correct about that sunlight and darkness is worse for keeping bread out, The breads in darkness and complete light stayed the same. They look like they have the same amount of moisture and they stayed the same. Even so, its better to store your bread in darkness since the bread will not get lots of warmth and moisture and could be kept for longer. Storing in a cupboard and dark area can keep bread col and dry so mold doesn’t grow.

Our projects application can help real world problems. As many people leave their bread out this experiment can help to show in which lighting condition it should be stored or kept out.

Sources of Error

1. The bread that got sunlight and darkness was beside the window which made it hardened because of the cold temperature from outside
2. The bread that was in complete darkness was exposed to a little bit of light because it had to be checked on

• How Does Mold Grow? | Science for Kids
• https://www.thespruceeats.com/where-not-to-store-bread-8549468
• Does Refrigeration Really Ruin Bread?
• How Many Types of Mold and Fungi are There?

We acknowledge the websites that we used for our research. We acknowledge our teachers and vice principal Ms. ElMoallem and Ms. Aly. We also acknowledge our parents who gave us the materials to help us with our project.