Lettuce (lettuce)
Once frozen, cell wall rupture causes lettuce leaves to go from crispy to mushy and translucent.
sauce or gravy
If thickened with starch such as cornstarch, they may end up turning into a watery sample. Freezing weakens the bond between the starch and the moisture it absorbs, making sauces and gravies thinner.
pudding
If you make pudding at home and thicken it with starch, you'll run into the same problems as sauces and gravy.
rice
Just like pasta, freezing cooked rice is never a good idea. It becomes mushy and tasteless.
pasta
Many websites promote making frozen dinners that you can reheat at the end of a busy day. That's all well and good, but don't add pasta to your dinner. Freezing can adversely affect pasta, turning it into mealy, soggy clumps.
cream soup
While soup freezes extremely well, anything containing dairy runs the risk of curdling or separating.
mayonnaise
Freezing turns the mayonnaise from creamy to lumpy. If you don't want a cheese-textured spread on your sandwich, choose not to put the jar in the refrigerator.
tomato
Cooked tomatoes can usually be frozen, but avoid freezing fresh tomatoes. Once thawed, they turn into a gooey mess.
whole egg
Eggs expand when frozen, causing their shells to explode. If you want to freeze eggs, be sure to remove the shells and place the whites and yolks in a freezer storage bag.
Fried food
While many fried foods can be purchased in the freezer section of the grocery store and reheated just fine, don't try this at home. Often, freezing fried foods will make them soggy, even if you re-fry them. Oil can also seep throughout the food, changing its flavor.
Previously frozen meat
Thawing and refreezing food is a big no-no. The USDA says it's completely safe to refreeze meat, but it can dry out the meat because moisture is lost during the thawing process.
cheese (cheese)
Freezing cheese will change its texture. Some cheeses become mealy, while others become heavy and thick. In most cases, cheese will last for several months when stored correctly, so you don't have to worry about freezing them.
potato
Raw potatoes become grainy when frozen. If you do want to freeze them, cook them first and then store them in a container meant for freezer storage.
canned food
Never put canned food in the refrigerator. This is because the liquid inside can expand to the point of breaking the seal, making it susceptible to bacteria and contamination, just like an egg in its shell.
fresh herbs
If you want to preserve vanilla, never store it in the refrigerator. Fresh skewers won't retain their color or appearance and will just turn into a brown mushy mess when thawed. Instead, choose frozen herbs designed for freezer storage.
shellfish
Shellfish is another food type that has regulations for storage in the refrigerator, especially after thawing. Shellfish such as shrimp, lobster and prawns can quickly grow bacteria if left at room temperature for as little as an hour, especially if the temperature is 90°F or higher. Therefore, refreezing and eating fish under these conditions may ultimately lead to food poisoning.
You can refreeze thawed fish within a few days, but it must be kept at refrigerated temperatures during this time and not left out for more than an hour. Be careful when storing and cooking shellfish to avoid getting sick. When freezing fish, place it in a zip-top freezer bag and remove as much air as possible, sealing it to prevent freezer burn - vacuum sealing may be a helpful method here.