Refrigeration is one of the most important and useful of the many technological advancements of the 20th century. It cuts down on waste by allowing us to store food for longer periods of time, aides in food transportation, and keeps last night’s pizza fresh so you have something to take the edge off your hangover. And while your fridge may seem like a miracle machine of munchie preservation, there are some foods that do not benefit from being kept in the fridge and can actually deteriorate more quickly if give the cold shoulder.
The age old battle of whether you should keep your grains on the counter or in the fridge comes down to crystals. Under a microscope, wheat flour has a crystaline structure that gives it its dusty, granular shape. When mixed with water and the other ingredients used in making bread, the crystals in wheat flour deteriorate, and lose their shape, allowing them to turn into a wet, sticky ball of dough. As the bread bakes, the wheat crystals reform, taking on slightly different properties that give bread that wonderful, springy softness. But as the bread cools further, those original crystals can start to reform. This is the process of staling. As the crystals reform and the water in the bread evaporates, the bread gets harder and harder, until you are left with a lump of stale bread fit only for making croutons. Keeping bread in the fridge may help keep mould at bay, but it will make it go stale much more quickly than leaving it on the counter. If you are concerned that you won’t finish your loaf before it goes bad, either by moulding on the counter or staling in the fridge, try freezing it. Freezing does not stale bread because it traps the water inside, allowing it to retain moisture once it has thawed. Just remember to keep it in a tightly sealed bag with as little air inside as possible.
This one has kitchen experts in disagreement. If your tomatoes are not quite ripe yet, keep them out of the fridge. But some experts say that it is okay to put them inside once they have reached peak ripeness. Fruit ripens when sugars break down. Cold temperatures can inhibit this process while other factors cause spoilage. The result is a tomato that rots before it ripens. There should never be any need to put them in the fridge because fresh tomatoes should really be eaten at peak ripeness. But if you have a bumper crop and just can’t eat them fast enough, a ripe tomato in the fridge is better than a rotten one in the trash.
The story here is just the same as tomatoes. Sweet, juicy pears need time and the right temperature to let those sugars break down for optimal ripeness. Pears are even more dangerous to put in the fridge though, because in addition to not ripening properly, refrigeration can make them go brown more quickly. Pears have very delicate skin and even the slightest little decrease in temperature can cause discoloration.
Frozen bananas are one of the most versatile ingredients around, but put them in the fridge and watch your dreams melt away. Another member of the sugar saving crew, bananas will go brown and turn way too soft if placed in the fridge. Even after they have reached peak ripeness, putting bananas in the fridge will cause the peel to become slimy and black. Yuck!
2) Open Cans
Say you open a can of beans but you only eat half of it. Don’t leave the rest in the can! metal is a poor storage choice for open food. It’s fine as long as the can is sealed, but once opened, exposure to the air can cause the metals to begin the oxidization process, releasing potentially harmful minerals into your food. It is always best to transfer any unused canned food into a plastic or preferably glass or ceramic container.
1) Unopened Cans
If a can or any other food package says “refrigerate after opening”, it’s best to not put it in the fridge until after it has been opened. Packages with seals (like the plastic seals you see under the lids of mayonnaise jars, ketchup bottles, and most other processed foods) are sealed using heat and slowly cooled to create suction. Sometimes air gets trapped inside. The air is safe and sterile because the package was sealed under hot conditions, but if it undergoes temperature fluctuations this could cause the seal to rupture. So putting your unopened ketchup bottle in the fridge may actually shorten its life.