Freezing – How to Get Frozen Egg Whites Out of the Ice Tray

Lay them out on a paper towel overnight so that the skins dry completely. This gives the benefit of keeping the frozen blueberries from sticking together without needing lots of freezer space to do a quick freeze individually on a sheet pan. Then bag in a freezer bag and freeze.

Note that whenever you freeze fruit, the liquid will burst the cell walls as it thaws, causing the resulting berry to be mushier. In my experience, frozen blueberries aren't good for eating alone. To bake with blueberries, thaw them by placing them in a mesh sieve or collander and running water over them until the water is clear off the bottom (no pigmentation from the skins, which may color your baked goods) and the berries are thawed. Dry the skins before using in baking.

Using these techniques I have not once had any of the 30 pounds of blueberries I froze this summer burst in the freezer and have successfully made many blueberry baked goods from the results.

I would say it depends. I find once you freeze an item the flavor/texture/propeties of the item is changed (for better or for worse) the next time you goto use it.

If your using caramelized onions in a soup, or stew, something where flavors blend together for a longer period of time, then yes go ahead.

however if your using the caramelized onions on top of a steak or something similar. Then my answer would be no.