Freezing excess food or meals is a great way to cut down on food waste and have meals prepared for whenever you don't feel like cooking up a storm. However, there are some tried and true tips you should live by when freezing foods: Let freshly-cooked foods cool off (via an ice bath) before putting them in the freezer; don't ever re-freeze something after it has been thawed once; do not crowd your freezer; and make sure you use those frozen foods within nine months.
Live by those rules, but also know that there are some foods that should never make their way into the freezer in the first place.
1. Raw vegetables and salad greens: Foods such as watercress, celery and romaine lettuce have high water contents. So, after they've turned icy in the freezer, they will thaw into a mushy mess. The lettuce will oxidize much faster after being thawed because the cell walls have been broken. Potatoes do not fair well when they are frozen, either; whole, uncooked potatoes will get ice crystals, then turn mushy after being thawed. It is best to simply buy fresh greens and vegetables when you know they will get used in the next few days. Squishy cucumbers? No thanks.
2. Eggs in their shell: Because liquids expand when they turn to a solid state, the egg whites will expand in the shell and potentially cause it to crack. A cracked egg is a bad egg because harmful bacteria could make its way inside. You can freeze eggs when taken out of the shells.
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3. Some dairy products: Milk will turn lumpy after you've properly thawed it, so drinking it would be unpleasant. Sour cream will separate out and become very watery; the same for cottage cheeses and yogurts. Don't freeze your regular yogurt in order to make frozen yogurt... just buy frozen yogurt. Blocked cheese will change in the freezer, and not for the better: It will usually become too crumbly to slice or grate. Soft cheese's moisture will crystalize in the freezer, and it will never again have the same gooey goodness.
4. Salad dressings: Vinaigrettes, mayonnaise, and hollandaise sauce are all emulsified, which means they have tiny fat droplets suspended in water. Because those two do not mix well, it easily separates out and turns watery when frozen. If you try to freeze mayonnaise-based salads or salad dressings, that is exactly what will happen. Use the same guidelines for ketchup (we've all been there, soaking our fries in water with little to no actual ketchup coming out).
>> Recipe: Freezer-Friendly Breakfast Burritos