We waste a lot of food out of fear: Experts estimate that $165 billion worth gets tossed each yearBut most expiration dates are largely made up. According to the National Resource Defense Council, the "sell by" dates do indicate not whether or not foods are safe to eat - they simply tell you when food will reach its limits for "optimal quality".

The handy website StillTasty compiles data from sources like the USDA, the FDA, and the US Centers for Disease Control and Prevention, as well as food manufacturers themselves. The site provides helpful tips on when to dispose of hundreds of household goods. 

Tips about the "sell by", "best by", and "used by" terms

The USDA advises you to purchase the product before the "sell-by" date, and the "best if used by (or before)" date indicates when the product will have optimal taste and quality. "Use by" dates simply indicate the last day the food will be at its top quality. 

The USDA notes that it's okay to eat these foods past the dates on the packaging - however, this does not mean we are invincible from getting sick. "If foods are mishandled," the USDA writes on its website, "food borne bacteria can grow, and if pathogens are present, cause foodborne illness - before or after the date on the package." The only exception is infant formula, as the USDA advises parents to not buy or even use baby formula once the "use by" date rolls around.

What about mold?

Generally, a rule of thumb to go by is to pay attention to when you purchased or opened the food, rather than what the packaging says.

Uncooked poultry

According to the USDA, poultry can be stored in a refrigerator for one to two days after purchase. If cooked and the packaging is unopened, it will last roughly three to four days. Once opened, the chicken will last three to four days, as well. StillTasty notes you can keep chicken in the freezer for nine months.

Uncooked beef, veal, pork, and lamb

Although the USDA advises consumers to pay heed to the "use by" date, you don't need to pay any mind to the "sell by" date. The product will stay good for three to five days after purchase. StillTasty mentions that you can keep beef in the freezer for six to 12 months, and it will remain top quality.

Eggs

Eggs are pretty controversial. But if eggs simply have a "sell by" date, feel comfort in the fact that you can store them for three to five weeks after purchase. You can keep them frozen for up to a year.

Bacon

Everyone loves bacon, but how long should bacon be kept in the fridge before you toss it? While the USDA advises you to adhere to "use by" dates, the "sell by" dates, once again, don't matter much. If left unopened, you can keep bacon in the fridge (40 degrees Fahrenheit) for two weeks. Once you open it, you have seven days to eat the bacon. 

Lunch meat

If your lunch meat has a "sell by" date rather than a "use by" date, if you don't open it, the USDA says you can keep it for two weeks. But once you open the package, you only have three to five days left. StillTasty adds that you can keep commercially packaged lunch meat (ham) in the freezer for one to two months!

Nuts

Commercially packaged nuts will stay for 10 to 12 months in the pantry, StillTasty says.

An opened jar of peanut butter

Once you open a jar of peanut butter, you can get three to four months out of it. StillTasty says you will get three months out of the peanut butter if you leave it in the pantry. However, you can (slightly) maximize the lifetime of your opened peanut butter if you refrigerate it - the shelf life will be three to four months.

Lasagna noodles

No need to regularly purge your cabinets of noodles. Opened or unopened, you can get three years out of lasagna noodles, notes StillTasty.

Chocolate

Boxed chocolates can last longer than you might expect, if stored properly. StillTasty advises you to store chocolate at room temperature to get six to nine months out of them. (Even if they've been opened.)

Additionally, StillTasty writes that you can extend chocolate's life by cranking down the temperature. "As a general rule, refrigerating chocolate can extend its shelf life by at least 25 percent, while freezing can prolong it by 50 percent or more. Place the original box in a heavy-duty plastic freezer bag, seal it tightly and then refrigerate for up to one year, or freeze for up to 18 months for best quality. Thaw frozen chocolates in the refrigerator," the website advises.

However, StillTasty mentions that this is not the case for luxury, artisanal, handmade chocolates - at room temp, they'll stay fresh for two to three weeks. 

Milk

If refrigerated, StillTasty writes that "Milk will generally remain drinkable for about one week after the "sell by" date on the package." You can extend milk's life to about three months by freezing it. (The texture might be grainy, StillTasty notes, but thawed milk works for baking.)

A general rule of thumb for milk is this: "sour smell, an off-white or yellowish tinge to the color, and a thick or clumpy texture" means it's time to toss the milk. 

Lettuce

Romaine lettuce will last about a week in the fridge. However, StillTasty writes, it doesn't do well if it's frozen. For optimal freshness, the site advises to not wash lettuce until you're about to eat it.

Yogurt

If you purchase commercially packaged, already refrigerated yogurt, you can keep it for about seven to 10 days after the "sell by" date. If you freeze the yogurt, you can get one to two months out of it. Opened yogurt, StillTasty notes, will taste optimal for five to seven days after it's opened.

How to tell if it's gone bad? Just check and use common sense. StillTasty says red flags include "a highly runny watery consistency, a clumpy texture, and a sour smell." If you see mold, throw out the whole package. ("Do not taste the yogurt first," StillTasty wisely advises.) 

Fresh, raw salmon

Unopened salmon will last one to two days from the date of purchase, notes StillTasty. However, if you freeze it (before the one to two days mentioned previously, that is), you can squeeze out an additional two to three months for optimal taste.

Ketchup

Left in the pantry, unopened ketchup will last around a year. Once opened, it will last around a month in the pantry and six months in the fridge.

Wine

The rules change for wine based on a few factors. While it's generally frowned upon to serve cold red wine, sticking opened red wine in the fridge will help it maintain freshness (it'll last an additional three to five days after you pop the cork). Stick opened red wine in the freezer, and it will stay for another four to six months! Opened white wine lasts just as long.

If you're a light drinker, it's wise to purchase a full-bodied wine (think merlot or syrah versus pinot noir), StillTasty says. Those variations of wine last longer.

Unopened red and white wine will last three years and beyond, depending on how fine it is. Nice wines can last up to 100 years!

Honey

Good news: Honey left in the pantry will last forever!

This article was originally published by Business Insider.

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