Yes, freezing horseradish root can prolong its shelf life. However, as with other frozen wasabi, horseradish also loses its pungency when frozen. It is not recommended freezing the horseradish root as a whole. You can either grate or cut into smaller pieces before freezing. Whenever you need it, safely thaw it in the refrigerator. Frozen horseradish is best consumed within 3 to 6 months.