When should we throw away food we haven’t eaten yet? How about canned food, flour, butter, beans and eggs? The expiration date is often not as important as we think, and sometimes it shouldn’t even bother us.

In some cases, expiration date is simply a manufacturer’s estimate of how long their product will retain its highest possible quality.

Food companies tend to be cautious in their estimates, knowing that not everyone keeps packaged food in a dark, dry place. When should we pay attention to these time limits?

Materials we don’t have to worry about

Vinegar, honey, vanilla extract or other extracts, sugar, salt and molasses will last almost “forever” without much change in quality.

Oats keep for about a year before they begin to spoil.

White flour can be used no matter how much time has passed, the New York Times notes in its guide. However, whole grain flour can become metallic after a few months.

The “whiter, longer” rule applies to other cereals as well. White rice, for example, lasts for years, while brown rice lasts only a few months.

Supermarket shelf-stable bread seasoned with oils (and preservatives) may stay soft for weeks in the refrigerator, but oven-baked sourdough bread will begin to spoil the very next day and mold before the week is up.

Dried beans and lentils remain safe to eat even years after purchase, but they become firmer and take longer to cook. If you’re not sure how old your pantry dried beans are, don’t cook them with acidic ingredients like tomatoes. Acid can significantly increase the softening time.

The spices are safe to use and the only “risk” is that they have lost their pungency.

Canned fruits, vegetables, and meats will remain delicious for many years if their packaging is left intact. In the case of a bacterial reaction, “bloating” of the package is a sign that should not be ignored.

Oils, even unrefined ones that are prone to rancidity, can stay fresh when stored in airtight containers.

However, the shelf life of what has been opened varies greatly, but “everything will last longer if we don’t store it next to or above your stove where it can be exposed to heat.”

The mustard stays forever. The ketchup will start to change color before the time is up, but it will still be delicious. Mayonnaise also has an extremely long shelf life, especially if it doesn’t contain ingredients like fresh lemon juice or garlic. (High concentrations of fat, salt and acids are the enemies of bacteria and mold).

It goes without saying that pickles and chili sauces (like Sriracha) stand it up.

Their expiration date in some countries is up to 30 days after the date of packaging. But they will probably “remain tasty for many more weeks,” comments the NYT.