For freezing, recommendations include the following: Freezing at - 20° C (- 4° F) or below for 7 days (total time) Freezing at - 35° C (- 31° F) or below until solid and storing at - 35° C (- 31° F) or below for 15 hours Freezing at - 35° C (- 31° F) or below until solid and storing at - 20° C (- 4° F) or below for 24 hours