Freeze-thaw cycle testing is a part of stability testing that allows you to determine if a product will remain stable under various conditions. This type of test puts samples through a series of extreme, rapid temperature changes that could happen day to day.
Freeze-thaw testing is conducted by exposing the product to freezing temperatures for 24 hours, and then allowing it to thaw at room temperature for 24 hours. The sample is then placed in a higher temperature for 24 hours and then placed at room temperature again for 24 hours. The sample is analyzed for significant changes. This completes one cycle. Multiple cycles can be used to test the stability of a product.