This article is all about the storage, shelf life, and spoilage of sesame oil. Learn how to tell if it’s bad, how long it lasts, and if you should refrigerate it.
Got an out-of-date half-open bottle of sesame oil and not sure if you can still use it? Does sesame oil ever go bad?
Or maybe you just opened a new bottle and are wondering if it requires refrigeration.
If so, you’re in the right place. Let’s get right into it.
Table of Contents
- Does Sesame Oil Go Bad?
- Plain vs. Toasted
- How Long Does Sesame Oil Last?
- Does Sesame Oil Need to be Refrigerated?
Does Sesame Oil Go Bad?
Yes, sesame oil has a limited shelf life. Its fat molecules begin to oxidize through a process called rancidification, which causes the oil to develop an unpleasant flavor and sometimes an off smell. This process is continuous, and once the oil becomes rancid and unfit for consumption, you should discard it.
Things work this way because oils (and fat-based products in general) are subject to rancidification. Over time, the fat slowly oxidizes and develops an unpleasant aroma and flavor.
The process is gradual and takes months. That means you won’t notice any changes if you use the oil regularly. You can only spot them if you compare a fresh bottle with one that’s been open for quite some time or if you get back to a bottle after a couple of months of not using it.
Plain vs. Toasted
Before we discuss how to tell if sesame oil is bad, you need to know the differences between plain sesame oil and toasted sesame oil. This way, you know what to expect from yours in terms of flavor and aroma.
Plain sesame oil is pressed from raw sesame seeds. That means it has little color and flavor, and its aroma is weak. That makes it a good substitute for vegetable oil for sauteing.
On the other hand, toasted sesame oil is made from toasted sesame seeds (as the name suggests), and it smells and tastes like, well, toasted sesame seeds.
Related: Do sesame seeds go bad?
Plain and toasted sesame oils aren’t interchangeable. The first is mostly used for cooking, while the other has a much lower smoke point and works best as a finishing oil.
How to Tell if Sesame Oil Is Bad?
Discard your sesame oil if:
- It smells off. If it smells like old paint or nail polish remover, it’s rancid. Same thing if it gives off a harsh smell that instantly repels you. Sesame oil should either smell neutral (if it’s the plain variety) or toasty and sesame-seeds-like. Anything else probably means that it’s off.
- You notice visual changes. If the oil has changed color, or the texture has altered, something is going on. The exception here is slight crystallization or more thickness, which are normal if you store the oil in the fridge or any other cold spot. If that’s the case, everything should get back to normal when the oil warms up.
- The taste is off. If everything seems okay up to this point, you need to try the oil to assess its flavor. If it tastes acidic, sour, soap-like, or unpleasant, it’s rancid, and you should discard it. Again, remember that plain and toasted have different flavors.
(The signs of spoilage for oils are pretty much the same. After learning the above, you also know how to tell if vegetable oil is bad and how to tell if peanut oil is rancid.)
Last but not least, if anything else seems off that isn’t mentioned above, trust your instinct and toss the oil.
Now, what if your oil smells a bit rancid but tastes okay enough to use? Can you use it?
Is Rancid Sesame Oil Safe to Eat?
Eating rancid sesame oil probably won’t have any negative consequences in the short term, like a stomachache or nausea. In fact, many of us routinely consume rancid olive oil (more on that in my article on how long olive oil lasts), and we don’t even notice it or know it.
That said, eating rancid (highly oxidized, basically) oil in large amounts can have some severe long-term consequences. Because of that, it’s best to avoid it if you can.
The bottom line is if you notice that your sesame oil is rancid, throw it out immediately.
How Long Does Sesame Oil Last?
|Sesame oil (unopened)||Best-by + 6 months|
|Plain sesame oil (opened)||9 months||1 year|
|Toasted sesame oil (opened)||4 – 6 months||6 – 9 months|
After opening, plain sesame oil retains quality for about 9 months if stored in the pantry or for about a year in the fridge. Toasted sesame oil has a shorter storage time of between 4 to 6 months in the fridge and up to 9 months if refrigerated.
Those periods are, of course, rough estimates, and how long it takes for your sesame oil to go rancid depends on a number of other things, including storage conditions, the oil’s quality, whether or not it’s refined, and how old it was when you first opened the bottle.
Plain sesame oil keeps longer than its toasted cousin and doesn’t need refrigeration to last a long time. It’s quite similar to vegetable oils in that regard, and you can use and store it the same way you go about cooking oils.
Toasted sesame oil has a somewhat shorter shelf life, but you can easily extend it by storing the oil in the fridge.
It’s important to note that the quality of toasted sesame oil matters more than plain sesame oil because it’s typically used as a finishing oil. If it tastes bad, it can ruin the entire dish.
Because of that, it’s much more likely that you’ll discard toasted sesame oil for quality purposes than that you’ll chuck the other one.
Now, what if your sesame oil is out-of-date?
Let’s talk about how you should go about it.
Expired Sesame Oil
Sesame oil has a shelf life of 1 to 2 years and typically retains quality for an extra couple of months past the printed date if you store it properly.
As I already mentioned in the section on spoilage, sesame oil doesn’t expire the way dairy does. Instead, its quality changes slowly over time. Because of that, there’s no set date or period past which you should discard the oil.
Of course, the best-by date on the label is a good starting point, but your sesame oil could keep for a couple of months past it just as well as it could go rancid a few weeks before it. It all depends on the quality of the oil, how long it’s been open, and where and how you store it.
So if your sesame oil is “expired,” but you’re comfortable with how old it is (e.g., it’s two months past its date, not five years; it’s not soy sauce that lasts years beyond the printed date), check it against the signs of spoilage I outlined earlier in the article. If anything is suspicious or iffy, err on the side of caution. Otherwise, the oil is likely okay to use.
Now, we all know that you don’t have to refrigerate canola oil, but what about sesame oil?
Does Sesame Oil Need to be Refrigerated?
Sesame oil doesn’t require refrigeration, but refrigerating it helps the oil last longer. Plain sesame oil keeps for about a year in the fridge, while it only lasts 9 months at room temperature. Similarly, toasted sesame oil retains quality for up to 9 months if refrigerated, while it only lasts 4 to 6 months in the pantry.
(The same advice works for most other oils. For example, avocado oil doesn’t need to be refrigerated, but doing so will help extend its storage time.)
In other words, to maximize the shelf life of sesame oil, refrigerating it is the way to go, especially if we’re talking about toasted sesame oil.
Of course, if you use up sesame oil quickly (e.g., within a few weeks to a couple of months), it probably doesn’t matter all that much where you store it.
Last but not least, refrigeration helps much more after you open the bottle. A whole unopened one will probably keep fine for months in the pantry.
Now, let’s finish off with some other storage practices worth keeping in mind.
How to Store Sesame Oil
Store your sesame oil in a cool and dark place, away from sunlight and sources of heat. Make sure the bottle is always sealed tight, and consider refrigerating the oil after opening so that it lasts as long as possible.
If you decide to store the oil in the fridge, remember that it might thicken a bit and pour more slowly. That’s normal, and everything will get back to normal once you let the fat warm up at room temperature.