 Listen to your freezer fairy this year. Make more use of your Christmas food. Prepare in advance and reduce food waste from leftovers by using your freezer like a pause button. It's safe to freeze food up until the use-by date. You can freeze meat and meals cooked from previously cooked and frozen meat. For example, the leftovers from your turkey. But once defrosted, the pause button is off and you should eat the food within 24 hours.