Does sesame oil expire?
In this brief guide, we are going to answer the question “does sesame oil expire” with an in-depth analysis of whether or not sesame oil expires. Moreover, we are going to discuss the shelf life of sesame oil, the proper way to store sesame oil, and whether or not you can reuse the sesame oil.
So without much ado, let’s dive in and figure out more about it.
Does sesame oil expire?
Whether or not sesame oil expires depends upon several factors including what you mean by expired sesame oil. If you mean that the flavor and taste of sesame oil will change after a certain time then, like all other foods, sesame oil can expire.
Sesame production has been recorded in the Middle East and India since 4000 years ago. About 60% of the world’s sesame production was from Myanmar, India, China, Ethiopia and Nigeria during 2011 (1).
What we mean by expired sesame oil is that such sesame oil will go rancid or go stale and it won’t have the same aroma and flavor as that of fresh oil. Moreover, it will also lose its antioxidant content. Losses on antioxidants are accelerated through their reaction with light, high temperature, and oxygen (5).
Sesame oil is an unsaturated oil and 80% of its fatty acids are unsaturated. Sesame oil is rich in vitamin E and its free fatty acid content is relatively low. This oil is highly rancid under oxidation conditions and gives a bad smell (2).
It is worth mentioning that you will find a “best by” or “ best before” date written on the bottle of your sesame oil instead of the expiration date. The “best by” or “best before” date that is written on the bottle of sesame oil refers to the quality rather than safety so sesame oil doesn’t necessarily go bad immediately after the best before date (6). It is the time during which you can enjoy the peak quality and flavor of sesame oil but you can still use sesame oil that is past this date as long as it was stored properly. Together with extrinsic factors coming from the packaging and the environment, the oil’s compositional aspects primarily influence its shelf life, giving it more or less sensitivity to light, O2, temperature, enzymes, and all the potential causes of shelf life reduction (3). The higher degree of unsaturation in the oils accelerates the oxidation process in oils and fats. Therefore, as a result of oil oxidation, the aldehydes, ketones, and short-chain fatty acids are created, which cause an unpleasant odor in oil (2).
There are certain indicators that you should keep into consideration to find out whether your sesame oil has gone rancid or not.
Sesame oil can go rancid and it can develop that unpleasant rancid aroma that is noticeable if you take a sniff test of the sesame oil (it won’t have the otherwise nutty aroma of the fresh sesame oil).
Moreover, if you feel some unpleasant taste or rancid taste while taking a bite of food fried in sesame oil then it means that your oil has gone rancid and it is better to discard it.
The nutrient profile of the sesame oil that has gone rancid is also degraded and it has lost most of its antioxidants.
You can read about the uses and benefits of sesame oil here.
How long does sesame oil last?
When it comes to the sesame oil, unopened sesame oil lasts for about 18 months or even more if it is stored in a cool, dry, and dark corner of your pantry away from direct sunlight and heat. It is the time during which you can enjoy the best quality of the sesame oil which means that you can still use properly stored sesame oil even after this time. According to the USDA, sesame oil has a shelf life of 2 years when kept unopened and stored at room temperature. After opening, the shelf life is reduced to 6 months (4).
Moreover, refrigeration can increase the shelf life of the sesame oil and sesame oil lasts for about 1 year when it is properly stored in the fridge at or below 40 degrees Fahrenheit. You should keep in view that refrigerated sesame oil can become cloudy and can even solidify. The storage at low temperatures may reduce the oxidation reactions, limiting the loss of antioxidants and extending the shelf life of oils (5).
It is worth mentioning that these figures are just the estimated shelf life of sesame oil and sesame oil can even last for more than this, provided that it was stored properly.
How to properly store sesame oil?
- You should store your sesame oil away from direct sunlight and heat. As sunlight and heat can increase the rate at which sesame oil can go rancid or stale (5).
- You can store the unopened sesame oil easily in a cool, dry, and dark corner away from direct sunlight and heat. Thus you can store sesame oil in your pantry or kitchen cabinet. You can store the sesame oil in the pantry even after it has been opened and it can last for a long time there.
- Moreover, you can also refrigerate your sesame oil to prolong its shelf life.
- You should close the lid of the bottle containing sesame oil as soon as you have poured the oil that you need so that it will minimize air or obnoxious agent exposure of your sesame oil.
Can I reuse sesame oil after frying?
Usually, tocopherols present in the vegetable oils are sufficient to protect them against oxidation at environmental temperature. However, at high temperatures of deep-fat frying, antioxidants with high efficiency are required to delay oil degradation. High oxidative stability of sesame oil compared with other vegetable oils is due to the large quantity of endogenous antioxidants and sesame oil can be used for frying purposes. However, after repeated frying, sesame oil can oxidize, producing free fatty acids, which are harmful to health. Because of the development of harmful and reactive oxidation products when vegetable oils go rancid, they may offer health hazards such as cancer and inflammation (7,8).
When it comes to reusing sesame oil after you have fried something like fish, chicken, or any other thing in it, you have to keep some things in mind.
Firstly, you should let the oil cool and afterward strain the sesame oil before storing it to get rid of the leftover particles of the previous food that you fried in it.
Moreover, there is no hard and fast rule regarding how many times you can reuse the sesame oil, but you should keep in mind that the quality and taste of oil deteriorate with each time you fry something in it.
Therefore you will notice that you won’t get the same flavor of the fried food after you have fried for the fourth time in the same sesame oil as you got when you fried something in it for the first time.
Thus, the time when you start to feel a noticeable difference in the taste and smell of the food that you fried in your reused sesame oil, you should discard the oil.
In this brief guide, we answered the question “does sesame oil expire” with an in-depth analysis of whether or not sesame oil expires. Moreover, we discussed the shelf life of sesame oil, the proper way to store sesame oil, and whether or not you can reuse the sesame oil.
- Ayana, Negash Geleta. Status of production and marketing of Ethiopian sesame seeds (Sesamum indicum L.): A review. Agric Biol Sci J, 2015, 1, 217-223.
- Chavoshizadeh, Sona, Sajad Pirsa, and Forough Mohtarami. Sesame oil oxidation control by active and smart packaging system using wheat gluten/chlorophyll film to increase shelf life and detecting expiration date. Euro J Lipid Sci Technol, 2020, 122, 1900385.
- Piergiovanni, Luciano, and Sara Limbo. Packaging and the Shelf Life of Vegetable Oils. Food packaging and shelf life. 2010, 317.
- FoodKeeper. United States Department of Agriculture.
- Mousavi, Soraya, et al. Evolution of Extra Virgin Olive Oil Quality under Different Storage Conditions. Foods, 2021, 10, 2021.
- Gravely, M. Before you toss food, wait. Check it out!. United States Department of Agriculture. 2022.
- Singh, Mukesh Kr, et al. Effects of Repeated Deep Frying on Refractive Index and Peroxide Value of Selected Vegetable Oils. Int J Res Appl Sci Biotechnol, 2022, 9, 28-31.
- Borjian Borojeni, M., A. Goli, and M. Gharachourloo. Effect of roasted sesame oil on qualitative properties of frying oil during deep-fat frying. J Agric Sci Technol, 2016, 18, 1531-1542.