Cooking oil and grease add flavor to any meal, especially when you are drying that thanksgiving turkey or browning your Brussel sprouts. It is all fun and games until you have to dispose of it.
This article will help you know when and how to dispose of it because doing it the wrong way may cause expensive consequences where spending on a plumber would be the price you pay.
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Does It Go Bad?
Cooking oil is something that we rarely buy with the expiry date in mind, at least most of us because it takes up to two years to expire. When it is unopened and stored correctly, it does stay for longer.
Like most food, proper storage is paramount in increasing their shelf life. Once you open it, it should last you a year without going bad. Store it in the pantry and away from direct sunlight. Do not store it in the refrigerator, though.
With time also, the taste of oil changes and becomes rancid. This happens despite proper storage and eventually, its quality changes. You will mostly note this when using it in a salad.

The taste is not as fresh, but the oil can still be useful in cooking. You will also note it has lost its quality by taking a whiff and will smell off. Also, take two tablespoons and heat it. If it smells off, then it is time to get another bottle.
You will not get sick from eating it while rancid, though. It only loses its healthy properties like the antioxidants found in olive oil. They become rancid when a chemical reaction happens that makes the molecules of the oil break down.
If exposed to air, the process is quickened and makes the oil vulnerable to the process. That is why proper storage is essential. When buying it from the store, make sure the oils are packaged in tinted glass containers.
Avoid the clear glass ones that may allow light in and speed up the spoiling process. If you buy the clear containers, cover them with foil on the outside, especially if they are big bottles and may take a while to get used up.
The Best Way To Dispose Of Used Cooking Oil
Like we saw above, you often end up with leftover cooking oil after deep frying or browning beef. The first thought would be to pour it out through the kitchen sink, which clogs the pipes or pouring it outside, which is downright unhealthy.
Reusing it is always an option, but if it is spoilt, there are easy ways of getting rid of it.
- Pour into a disposable container - Let it cool first, then pour it in a non-recyclable container with a lid then, throw it in the garbage. Make sure it will not spill. Non Recyclable containers are such as milk cartons or wax or plastic-lined paper containers. Styrofoam container is also a good option.
- Let it solidify - To dispose of it well, refrigerate it first to make it hard. Transfer it to an old can and put it in the freezer. Once it is solid and can come slide out of the can, throw it out. If you have just a little of it, cool it, then put it in a plastic trash bag. Close it then dispose of it.
- Garbage disposal system - This is for those who regularly fry stuff and need to get rid of used oil. The more straightforward way would be to get a grease disposal system with a plastic receptacle lined with aluminum foil and hold 32 ounces of oil. Get a bag where you will be pouring into then sealing it well for disposal.
- Collection program - Some towns have collection programs that collect used cooking oil and turn it into biodiesel. Check Earth911 to see if there is any recycler near you that can help with that.
Can You Reuse Cooking Oil?
Many people are skeptical about reusing oil because it seems messy and unhealthy. You may have overestimated and used too much oil. Trust me pouring it out would be a stab in your wallet, especially if you used peanut oil.
Reusing oil is not a bad idea, but you will need to consider next time you use your frying oil.
- Choose your oil of choice wisely. Frying occurs at high temperatures, so choose an oil that has a high smoking point. These include peanut, canola, or vegetable oil. Olive oil is too expensive and does not have a high smoking point.
- Get your frying technique right. Carefully maintain the oils temperature to prevent the food from being soggy, which happens when the oil is cold or blitzed on the outside and raw on the inside when the oil is too hot. When the oil is too hot also, it breaks down quickly, and its longevity will be affected. Broken oil is unstable and turns food greasy. Get a thermometer that can handle the high heat.
- Filter the fat - After every fry, make sure to filter the fat after draining it. This is to separate it from any impurities and food bits. If you reuse it with the crumbs next time, it will spoil the oils integrity. Use a cheesecloth in a metal strainer after you bring the oil to room temperature. Do not forget to store it in an airtight container.
- Label and separate your oils - You may want to reuse the oil you fried chicken with to fry your doughnuts. The two flavors may overlap and may taste nasty. As you store the used oil, label it so that you can know what food to use.
- Dont use it only to deep fry. Use it as your usual cooking oil. Take tablespoons of the oil as you cook other meals.
- Do not reuse the oil too many times - We are pro-reuse oil but do not overdo it. Whenever you reuse the oil, it gets destabilized until it finally decomposes. If the oil looks cloudy or has foam on top of it, then dispose of it. Make sure to smell the oil, and if it has a rancid smell, then it is time to toss it off.
Other Uses Of Used Cooking Oil
After reusing your oil or arent buying the reusing idea, you could still use the oil for different things in the house such as:
- Soaps.
- Ant poison.
- Animal feed if you are a farm head.
- Dust suppression when doing a DIY project
- Leather preservative. You could wipe your leather furniture with it on a cloth to preserve it
- Hair moisturizer.
How To Clean Cooking Oil
The usual way of cleaning used oil is usually pouring it through a sieve or a filter, but there are other ways you should try next time.
- Use cornstarch - This is a faster one where every cup of oil whisk a q-quarter cup of water and one tablespoon of cornstarch. Add it to the warm or already cooled oil then heat the mixture gently. Stir it with a heatproof spatula till the cornstarch mixture solidifies. Get it off the stove and pour it through the strainer then use it.
- Use gelatin - This is a new one but quite efficient for every quart of oil use a teaspoon of gelatin for half a cup of water. Mix the gelatin mixture till it hydrates. Bring the mixture to a boil until the gelatin dissolves. Pour the gelatin mixture in the dirty oil, cover it, and put it in the refrigerator. Let it rest overnight. The following day the gelatin will have solidified with the impurities leaving the oil, which you can pour in a separate container for storage.
- Filtering cooking oil - You could also decide just to go the easy way and filter it using a paper towel or cheesecloth-lined kitchen strainer resting in a clean container. Make sure the filters fit on the container to avoid pouring any cooking oil.
Storing Cooking Oil

As we covered above, make sure to keep oil away from direct sunlight or heat. It should also be in an airtight container to avoid getting exposed to oxygen to prevent oxidation, which makes oil rancid.
The best place to store it is in a dark pantry away from kitchen appliances. Other people prefer to put it in the fridge, which is also an option but for peanut and canola oil. All you need to know is store it in an airtight container away from sunlight, heat, and oxygen.
You can keep them at room temperature. Delicate oils such as hazelnut, grape seed, and sesame oil go rancid quite quickly after being opened. It is best to refrigerate them after opening.