Expiration dates you should and shouldn't pay attention to

Thanks to modern preservation techniques and the widespread availability of refrigerators, food can last for quite a while. Since it can be tricky to know just how long food is good for, many items come marked with an expiration date. In many cases, however, that expiration date is just a guideline and the food can still be consumed after the expiration date has passed. According to the Natural Resources Defense Council, 40 percent of food in America goes to waste, and a large reason for that is because most people are throwing out food that is still good

While there are some expiration dates you should stick to, others can be viewed as loose guidelines. So how can you tell the difference? Here are some of the expiration dates you can totally disregard and some you should never ignore.

Eggs

It can be hard to tell whether or not an egg is still safe to use unless you crack it. You may have heard that old eggs immersed in water will float. This is true, but that doesn't necessarily mean the egg isn't safe to eat. Eggs are usually good for 3-5 weeks after you purchase them, but can last even longer if properly refrigerated. 

The surest sign of a rotten egg is its smell. If you crack open an old egg and it gives off an unpleasant odor, then you should toss it (and the rest of the carton) into the trash.

Milk

Generally speaking, milk is good for up to a week after the sell-by date, although you should still give it a sniff test to be sure. If the milk smells funky, has changed color, or gotten thick and clumpy, pour it down the sink.

Keeping your milk properly refrigerated will help it last longer. This means that you should keep it on a shelf inside the fridge rather than storing it on the door, where it's exposed to temperature fluctuations.

Cheese

The shelf life of cheese depends on the type of cheese. While sprouting mold might seem like a pretty good sign that food should be thrown in the garbage, some cheeses (like brie) naturally grow white mold that's safe to eat. With the exception of blue cheeses, growths of orange, red, blue, or green mold are signs that your cheese has gone bad. In most cases, you can simply cut off the moldy part of the cheese and safely eat the rest.

Drier cheeses will usually last longer than moist cheeses. Be careful with pre-grated cheeses,as mold growing on grated cheese can't simply be cut off and you'll have to throw all of it away.

If the cheese looks and smells fine, it's probably safe to eat. The flavor of cheese intensifies over time, but that doesn't mean your cheese has gone bad. If, however, after taking a bite you begin to feel a tingling sensation in your mouth, spit it out because this means your cheese needs to be thrown out.

Leftover food

Leftover food should be eaten pretty quickly. Make sure to put any leftovers in the refrigerator as soon as possible; the safest length of time they can stay at room temperature is two hours. Refrigerating the food slows down the growth of bacteria, so it's safe to eat leftovers the next day, but don't wait too long. Leftover foods are only good for about two to three days, after which they should be thrown out.

Raw meat

Raw meat is one thing you should definitely follow the expiration date on. Most meat, fish, and poultry should only be stored in the fridge for a couple of days, though thicker cuts of meat (such as a roast or a steak) can last for up to five. If you're not planning on cooking these foods within the first few days after purchasing them, store them in the freezer. Most meats can last for months when frozen.

Honey

Honey has a reputation as being a food that never spoils. Since it has very little moisture, organisms can't live for very long in honey, which means it's very difficult for it to go bad. That doesn't mean you can just leave an open jar of honey sitting out on your counter, though. In order for honey to remain unspoiled, it can't be exposed to moisture. To keep your honey fresh and sweet, seal it tightly and store it in a cool, dry place.

Juice

Fruit juices are usually acidic, which means it's harder for bacteria to form in them. This means fresh fruit juice is usually good past the expiration date. Vegetable juice, however, is more likely to go bad around the expiration date, although it may last longer if it's blended with fruit juice.

Juices that aren't made from fresh fruit usually have a lot of added sugar, which acts as a preservative. While fresh apple cider will only stay good for a week or so after the expiration date, bottled apple juice can stay good for up to three months. Juice that has gone bad will usually smell sour or grow mold.

Infant formula

Infant formula is the only food that is federally regulated and required to carry a use-by date by the Food and Drug Administration.This is one expiration date that is absolutely vital to adhere to, especially since your baby can't tell you if the formula tastes off. Stick to the date printed on the packaging, and make sure to use it within 24 hours after opening, or according to the manufacturer's instructions. Also make sure to follow the storage instructions to ensure freshness. Infant formula needs to be stored in a cool, dark place with a stable temperature.

Canned goods

While canned goods do often have expiration dates printed on them, you don't need to follow them. While some acidic foods, such as canned tomatoes, are only good for a year and a half, most canned goods (even meats) can last for years. For the best results, store canned goods in a cool, dry place. Keeping them in a warm environment will diminish their lifespan and also affect the quality of the food whenever you finally eat it.

Pasta

The shelf-life of pasta depends on how it's made. If you're storing fresh, homemade pasta, it'll only remain good for four or five days since it's made with eggs. Dried pasta, on the other hand, is not usually made with eggs and therefore can last for one to two years past the expiration date. Dry pasta will last longer if kept in its original packaging, or if stored in a tightly-closed container to keep out air.

Bread

Bread is usually safe to eat as long as you don't see any mold growing on it. While most people store bread at room temperature, refrigerating it will lengthen its lifespan. While this does run the risk of drying out the bread, the bread will still be edible. You can also freeze bread for a few months. If you prefer to keep your bread stored in the pantry, it should remain good for five to seven days.

Yogurt

The shelf life of yogurt depends on whether or not the package has been opened. If the yogurt has remained sealed, it can still be good for one to two weeks after the printed expiration date if it has been properly refrigerated. Opened yogurt should be eaten within five to seven days for the best quality, though it will likely still be good after that. Watch out for any mold growth, as this is a sign the yogurt has gone bad. Also discard it if it has been left out at room temperature for more than two hours.