How to freeze fresh ingredients without them freezing together

Question

I am looking to freeze some cooking apple slices, but this question applies more broadly to any fresh ingredient with a non-trivial water content.

Just dumping them in a freezer bag/container and sticking them in the freezer inevitably results in the individual pieces frozen hard together. Is there a "home cooking" method to prevent or reduce this problem?

Things I've tried:

• For finely chopped ingredients, I've found removing the container periodically -- while it's freezing -- and stirring or agitating the contents, to break things apart, works OK. (It doesn't work well for larger, or more fragile ingredients, such as apple slices.)
• Separately laying out ingredients on a baking sheet, freezing that and then decanting the result into a container. This works, but it has practicality problems (it takes a lot of prep time and freezer space) and potentially hygiene problems (uncovered ingredients, run-off perhaps, etc.).

Is there some trick that works better?

Answer 1

Your second method is the traditional solution, known as open freezing.

There shouldn't be any hygiene problems as the regular contents should be well-sealed, and you don't want things to be dripping wet when they go in. The big issue is freezer space compared to my preferred storage in boxes. Prep time for laying out the slices once cut isn't much more than tipping them into a bag, but with apple it's worth dipping them in dilute lemon juice first, as they'll brown while you're working. Finding some trays that stack helps with the space issue.

The link suggests putting each tray in a bag (presumably a large one) if you're not going to transfer the frozen fruit into a sealed container as soon as it's frozen. This would help if you're worried about contact with other freezer contents too.

Forward planning saves effort overall. I harvest (black/red/white) currants into boxes for freezing, because I know I'll defrost them all at the same time when I want to cook with them (jam or sorbet) once they're all ripe. I know I don't need them loose. But some other home grown stuff does get frozen open, so I can use small quantities as required.

Answer 2

Consider freezing slices in layers in a large box (temporary, just until they're frozen). Separate the layers with silicone or plastic sheets (not cling film) just the size of the box. Lemon juice is almost necessary to preserve the fresh colour, and you can also spray the slices with lemon juice to avoid too much water and tap them with paper towels as you go. If you're not worried about sugar, sprinkle the sheets with caster sugar and separating frozen slices from the sheets will be a breeze. Instead of caster sugar you can also use bread crumbs (coarse work better).