There are a lot of myths surrounding re-freezing food, but you should never refreeze food that has been defrosted. However, if the defrosted food has then been fully cooked and allowed to cool, it can be stored in an airtight container or zip lock bag and frozen again for use at a later date.
Try to expel any air from the zip-locked bags to prevent the food from drying out.
Did you know?
You can refreeze previously frozen food once it is thoroughly cooked.