Does Grape Seed Oil Go Bad?

So there’s this half-open bottle of grape seed oil in your pantry that sits there for who knows how long. You switched to a different cooking oil some time ago and totally forgot about this one. Now you want to finish the bottle, but you notice that it’s past the date on the label. Does grape seed oil go bad? If you prefer to avoid waste, but at the same time you don’t want to make anyone sick from eating spoiled oil, that question is the first one that comes to mind. Well, the answer to this question is a bit more complicated than a simple yes or no. To answer this question for your specific situation, you need to learn a bit about storage, shelf life, and going bad of grape seed oil. In this article, we go through all of those topics.

Store Grape Seed Oil in Dark Bottles
Image used under Creative Commons from Paul Haahr

How To Store Grape Seed Oil

Storing grape seed (or grapeseed) oil is no different from storing other oils, like sesame oil or peanut. That means you should keep it in a cool and dark place, away from sources of light and heat. The ideal storage temperature is between 68 to 77 Fahrenheit (or 20 to 25 Celcius). That means you can store the oil in either the pantry or the kitchen. Just make sure it’s away from the oven, as frequent temperature fluctuations may cause its quality to degrade faster.

Once you open the bottle, remember to always keep it sealed tightly when not in use. The rest of the guidelines don’t change.

You can also refrigerate this oil to slightly extend its shelf life. An added bonus is that unlike other oils, for example, canola oil, grapeseed oil doesn’t get cloudy when refrigerated. That makes it a perfect oil for many dressings, homemade mayo, and other foods that require refrigeration. Please note that refrigeration is totally optional.

How Long Does Grapeseed Oil Last

The shelf life of grapeseed oil is not that different from other cooking oils. As usual, the bottle comes with a best-by date on the label. That date is more about freshness than food safety. If you adhere to the storage guidelines I outlined earlier, you can expect the oil to last in excellent quality at least a few months past that date.

Once you open the bottle, the oil gets access to “fresh” oxygen, and the process of oxidation starts to speed up. Oxidation results in the oil going rancid. However, that’s a slow process, especially if you open the bottle rarely and close it tightly as soon as you’re done. Nevertheless, you can expect the oil to retain its freshness for about half a year in the pantry and about a year if stored in the fridge. Please note that those are rough estimates and your specific situation might be different.

PantryFridge
Grape seed oil (unopened)Best by + 3 – 6 monthsBest by + 6 – 12 months
Grape seed oil (opened)6 months1 year

Please note that the periods above are for best quality only.

How To Tell If Grapeseed Oil Is Bad

While oils usually do not mold or rot in the traditional sense, please keep an eye out for any signs of mold, discolorations, off smell, or change in taste. If any of these occur, discard the oil.

What’s much more likely to happen is that the oil goes rancid. Rancidity occurs when the oil is oxidized, which can happen with exposure to light, heat or oxygen for extended periods. While rancid oils aren’t necessarily unsafe to eat, their nutritional value is diminished and they sure as hell don’t don’t taste good. If the grape seed oil develops an unpleasant odor and taste, it most likely is rancid. Be sure to give the oil a good sniff before using to check for rancidity. If everything with the oil seems to be okay, and you don’t store it for much longer than recommended, feel free to use it.