Science Buddies: "Ask an Expert"

Hello!

I am currently in the middle of the science fair project Mixing Your Own Marshmallows. Deciding to follow the Make it Your Own, I varied the cooking temperature of the marshmallow recipe and performed density and melting tests. I have gathered my results, but am currently struggling with an in-depth explanation for the results.
For the density tests, I found that the higher the marshmallow syrup is cooked to, the less dense the marshmallow becomes.
As for the melting tests, I discovered that the higher the marshmallow syrup is cooked to, the longer it took for the marshmallow to fully melt.
I have scanned through many websites, but still do not fully understand why the results are the way they are. I would deeply appreciate a guidance toward the explanations to these tests to complete my science fair project.

Thank you!
- Jordan

Hi Jordan,

Regarding your first question, density=mass/volume so when the volume increases, density decreases. When you heat something up, such as a marshmallow, the particles in the marshmallow move faster, causing the marshmallow to expand and increasing its volume, which decreases the density. As for the second question, I'm not entirely sure without having seen your experiment, but it's possible that cooking at a higher temperature evaporated more liquid from the syrup, creating a marshmallow with a more concentrated sugar content that would take longer to break down when you melt it. I hope this helps!

Sincerely,
Elena

Thank you!