Nucleation and crystal growth

How do you make rock candy and chocolate fudge? What makes one sugary sweet hard and crunchy but the other soft and chewy? Cammie provides an answer through a discussion of nucleation and crystal growth.

MATERIALS SCIENCE TETRAHEDRON:
Curious about the materials science tetrahedron? Watch this video to learn more:    • What is materials science?  

OUTLINE:
0:00 Introduction
0:24 Ming’s fudge conundrum
0:43 Crystalline materials
1:21 How do crystals form?
2:02 Making rock candy
3:31 Homogeneous nucleation
4:35 Heterogeneous nucleation
5:41 Distribution of crystal sizes
6:30 How to prevent grainy fudge

CREDITS:
Written, presented, and edited by Camille Farruggio and Mingyu Yang
With additional input from Ethan Rosenberg, Robin Lindemann, and Jacqueline Baidoo

ACKNOWLEDGEMENTS:
We are grateful for the support of the MIT Department of Materials Science & Engineering (dmse.mit.edu) and Dr. Rohan Kundargi, K-12 Outreach Coordinator of MIT's Office of Government and Community Relations.

ACCESSIBILITY:
[email protected]

CONTACT US:
If you have a food/materials-science question that you’d like to see featured in a future video (maybe even with you in it!), please reach out at [email protected]. You can also keep up to date on Twitter @foodsci_mit.