How Long Cooking Oil Is Good For After Being Opened - And When To Throw It Out

When you think of pantry staples that seem to last forever, cooking oil probably comes to mind. However, even that has an expiration date, and it's probably sooner than you'd expect. It's true that not all oil is created equal, so each one has a slightly different time it goes off by. In general, though, you shouldn't keep an open bottle of oil for more than a few months.

When closed and fresh, a bottle of olive oil or vegetable oil can still be usable for a year and a half to two years. That being said, the USDA instructs that an open bottle of olive or vegetable oil should be disposed of after only four months. Canola and avocado oil should last you four to eight months, and corn oil can last six months to a year in good storage. Expiration dates may move up considerably if oil isn't stored well.

There are a few ways to tell if your oil has gone bad, having to do with changes in consistency, appearance, and even odor. Oil should have good clarity, a clean smell and taste, and a smooth consistency throughout. If you notice your oil has changed in any of these attributes, it's probably time to throw it away. Oil that's going bad may not actually make you sick, but cooking with it can taint the flavor of the food and ruin your meal.

If you're unsure whether your oil is good or not, there are a few ways to make certain. The easiest sign oil has spoiled is if it's turned dark and cloudy. This indicates chemical changes in the oil and means it's probably going bad. Bad oils have a waxy, musty, and sour odor. If you see sticky, gloopy parts to the oil when you pour it out, that's another sign it's expired. When all else fails, give the oil a tiny taste, and if it's bitter or rancid, that flavor will be hard to miss.

There are some methods to extend the longevity of your cooking oil, but even these won't keep it good forever. Store oil in a dark and cool place when not in use. Different oils are suitable for different cooking needs, so keeping only the oil you use most regularly out in the open is probably best. Don't keep any strong-smelling substances near the oil, as it can absorb some of that scent. Another great hack is to actually store open oil in the refrigerator, as the lower temperature will extend its lifespan.

Once it's time to get rid of your bad oil, make sure you dispose of it safely. If you dump it down the drain, it can mess up your plumbing. Make sure you mix it with absorbent substances before putting it into trash bags so it won't leak everywhere. You can also check for local disposal programs online, so that experienced professionals can handle the oil properly. No matter how long your oil ends up lasting, it's still smart to keep it out of your drains and local environment.