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Storing vegetable oil

How long can I store a gallon of vegetable oil? Thanks.
Hi, R.

You probably already guessed the answer begins: "It depends..."

When you start with an oil that is well filtered so it doesn't have any fruit, seed, or nut solids, it lasts better. In India, it is hot and there is little refrigeration. Butter spoils quickly, but ghee, butter oil made by clarifying butter and removing every bit of the water and dairy solids, is stored or saved.

Some delicate oils such as almond, walnut, grapeseed, sesame, go sour fast. Buy from a place with good turnover in exotic groceries; anything which has dust on it to start with is too old to store.

Soybeans have an enzyme which breaks down the fats when the bean is crushed, soy oil is a good one not to store. Also be aware that non organic oils concentrate the pestcides in the parent plant, a real problem with cotton seed and peanut oils.

Besides time, the three enemies of edible oil are light, heat, and oxygen. So, a glass or clear plastic container which is half full (so it has a large surface exposed to air) and stored in a place with uncontrolled temperature will oxidize or "go rancid" much faster than a metal container filled to the brim and stored refrigerated.

Every time the can is opened, more oxygen gets in, so pour from your stoirage container into a smaller bottle for use. It's still better to keep both refrigerated.

If you already have it and are wondering whether to make paint or salad dressing out of it, smell it when you first open the container. The fresh, not bitter or stale odor is a good sign it is still fresh and edible. When you heat it the first time, pay attention; a barely rancid oil has a tattletale aroma at this time which is different from fresh.

If you are getting ready to store it, the old wives' trick is to put some vitamin E oil in it before sealing, as an antioxidant. No one can afford to use too much!

Fresh, properly stored oils, the professional estimate is store up to one year. I have personally eaten properly stored olive oil much older than this with enthusiasm and no bad effects.

If you want to buy a gallon because of price or quality, consider co-oping the cost with friends and dividing it up into containers that will fit in your refrigerators.

Hope this helps. If you need more specific information, please fill me in on the details of your situation.

Keep on cooking, Ellen

Marion Abramson
I made brownies (from a mix) that required 1/2 cup of vegetable oil. I used oil that I believe was rancid. The expiration date was 11/00, which made it a year old, and it smelled very funny. My husband and I each ate one brownie then I threw the rest away. What kind of side effects can be expected from using rancid oil?


Well, it tastes bad! Rancid oil uses up your anti-oxidants, but a small amount is not likely to do longterm harm. It is a great idea not to use or cook food that smells funny, eh? Ellen
Mei Bisaillon
I am wondering if cold pressed olive oil can get rancid and needs to be stored in the fridge.
Cold-pressed oils are delicious but fragile. In the refrigerator is good. Since olive oil with its healthy monounsaturates thickens up when cold, use a widemouth container (lightproof is better) and spoon out your weekly amount into a convenient holder to keep at room temp.

Keep on cooking- Ellen

Zahid Nazeer
Please tell me at what temperature (oC) corn oil, Soya oil, sunflower oil & sesame oil gets rancid.

Thanking you


Do i store pure butter ghee, which came in a metal container with plastic lid on, in the fridge or in the ladder?

thanx a bunch!

These question go together. The longer you want to store, the more important to refrigerate/ keep under 40F. Room temps below about 75F are good for relatively short term storage, like a month. The warmer it gets, the faster it oxidizes.

Hope this helps. Ellen


What is the best way to remove the odor of rancid oil from an oven?
Bad luck! Unfortunately, the rancid oil odor penetrates the oven spills right down to the metal. The only way I lnow of, is to completely clean the oven and also to wash all the racks and broiler pan in the dishwasher or with a foodsafe penetrating cleaner. Sorry! Ellen

What do you do with deep fat frying oil, vegetable oil, after it's been deep fat fried in? I'm in a debate with my husband. I think we should refrigerate and he thinks it's ok to leave it out.
Thank you,

Storing vegetable oil- used deep fat frying oil
You are dealing with two issues when ytou reuse fats and oils, flavor and health. Once heated to frying temperatures, oil begin to change from oil to, basically, varnish. So one idea is to select an oil that breaks down less easily, then clean out as much as you can of the flavors and bits left over from the frying.

So I don't reuse oil from frying fish, for example.

First, I use peanut oil, it breaks down less than any other vegetable oil when you fry with it.

Second I clean it after frying by frying some potato chunks and then filter it through a coffee filter, or several, before storing it.

And because I am concerned about the breakdown, I DO store it in the refrigerator, in a light resistant can or container, this is a question of chemistry.

Millions of people have not done all these things, reused oil a lot and done- OK as far as we know. Some even store it in the cooking pot, with no care. Their fried foods don"t taste nearly as good as those made with clean oil.

Hope this improves your discussion, Ellen


Peanut oil - storage
Since I don't have a ton of refrigerator space, can I store used penaut oil in the freezer?

Many thanks


after frying a turkey in peanut oil would it still be ok to use even if it is not been refrigerated for a few days? i have asked a few people and some said they would refrigerate it because of the drippings f the turkey being in it. others said it should not matter since the oil will get hot enough to kill any germs. which is true?



Eek! Poultry is the most prone to salmonella. Don't risk it! You could maybe borrow space in a walkin or cold room
I have peanut oil that is 2 years old. It has been kept in the fridge cold enough to solidify in a full container. I have used it twice. It smells fine. However, I did not filter it after the last use, but it went immediately back into the fridge as soon as it cooled enough to not melt the plastic bottle that it is stored in. Ok to use, or am I dreaming?

I have approx. 2 gals of peanut oil, unused, stored in a plastic container in the garage. The temperature in the garage is a constant 70 degrees, and there is no direct sunlight on the oil. I'm getting ready to deepfry a turkey today and may need a little extra oil to make up the difference if I'm short a little. The oil I'm using is fresh, and is pale yellow in color. The oil which is 1 yr old is a little darker in color, but doesn't seem to have any type of peculiar odor to it. I'm wondering if this stuff is safe to use or should I pitch it. Thanks.
I mostly use olive in cooking however on occasion use vegetable oil in baking. I try to buy the smallest bottle possible. I notice however that after being in the cuoboard for several months it developes a funny smell. Will storing it in the refrigerator keep that from happening. I used oil once that had that smell and whatever I baked had the same taste.
Can I freeze Peanut Oil?
Kase Kasameyer
Cooking with vegetable oil
I sprayed either Albertson's Olive Oil or Buttery Spray on a Rushco non-stick broiler pan and then broiled chicken. Nothing stuck to the nonstick pan except the sprayed on oil/butter. I can't get it off. Will it turn rancid so that the broiler pan can no longer be used? Alternatively, any ideas on how to get it off? I have used Cameo with no result. Thanks

An idea for removing the cooked on oil- ammonia soak. Put the affected tray inside a glass or enamel pan, put the whole thong in a big heavy plastic bag, then add a cup of plain ammonia into the larger pan and a cup of water and seal up the bag for 24 hours. It is convenient to put it in the oven, but tape over the knob so no one turns it on! At the end of this time, it may have loosened up the crud.

It is fine to freeze pure oils.
I always strain after frying, and do not reuse oil which has fried protein foods (fish, chicken).
Off smells or flavors in unused oil are a sign of oxidation/ rancidity, and refrigerating WILL slow down the process and help the oil stay fresh longer.
Can you reuse vegetable oil used for frying that has been stored at room temperature. I have no problem reusing it as long as it has been filtered and stored in the refrigerator. But this has been left on the stove (covered) in a cast iron pot for the last two weeks. Can't remember what was fried in it- probably french fries. It does not smell like food nor does it have a rancid smell. I just feel that it is not good to reuse if stored in this manner.
Why is it that some deep fried food in Chinese restaurants have an ammonia-like smell? This is especially true in foods which are coated in batter and then deep-fried?

Is this safe?



I think this is a rancid oil smell. Not every restaurant keeps the kitchen beautifully clean! Also, Chinese foods cook at very high temps, so the oil needs to be changed /filtered more often.

Is it all the fried food ata certain restaurant, or just certain foods? Basic rule; if it smells bad, dont eat it!

I make a chutney style dish and bottle it for sale. A lot of people love the flavour. A lot of oil is used in the recipe and I was thinking of bottling the oil which would have cooked vegetable and spice residue in it. Would this be safe and what would the shelf life be? I would suggest refrigeration after opening, but should it be sold refrigerated?
Thanks Marion

Dear Marion,

Your product sounds delicious.

I am not the right ;erson to ask for this info. You need to talk to a food science department at your local state university about storage, etc, and to the food regulation and food law persons in your area. In the US, the regulations for food prep are usually under the local health department while the sale laws are diifferent. States have different food laws, which is one reason so many food companies are registered in Pennsylvania.

Demetro aka Tuck
I have spray bottles for oil , I have found after a few refills the oil became rancid. I feel now that I didn't clean enough between refills . Is there a way to clean (remove odor)from food storage. I also found some grain did the same too. Some containers are glass as well metal and plastic .

I have used the oil sprayers, I like the choice of good oil, but had the same problem with getiing them completely clean between fillingings.

A dishwasher, or repeated washings with dishwasher type soap and hot water may work for your storage items. Do not forget the insides of the lids. WEAR GLOVES!!! The cleaner is quite corrosive to skin. Restaurant supply houses sometimes stcok food-safe degreasers which may help.

We are frying a Turkey this year for Thanksgiving and was wondering if we can save the peanut oil for next year? If so, how do we store it and does it have to be filtered? if so, how do I filter the peanut oil?

Please be very careful- 15 people in the US burned down their houses last Thankgiving deep frying turkeys and hundreds were severely burned. Really! How are you going to lift the 20 pound, 300 degree hunk out of that oil?

On to the oil storage question. As mentioned above, I do NOT recommend long storing of oil which has been used for cooking meat or especially poultry. If you use peanut oil and keep it at 360 or under, you could clean it up (cool, strain through layers of cheesecloth in a colander or large sieve, store in clean capped containers) and offer it to any homeless/ charity kitchen for immediate use. Call them ahead to arrange; if it is a charitable organization, you might even get a donation credit.


From the Peanut Sheller's of America's website:

Peanut oil may be stored for six months to 1 year if stored in a tightly capped bottle away from heat and light. If the oil has a funny smell, it will impart that flavor to the foods that are cooked in the oil. The oil should be discarded if there is an off aroma associated with it.

Butter outside the fridge
Hi-I took butter out of the fridge about 7 days ago, meaning to soften it to use for cookies. I got to busy and didnt make the cookies, and am wondering if the butter is ok to still use? It smells and looks ok, and I know that people were using butter for thousands of years before any type of cooling methods were available. I hate to waste it because its so expensive. Thanks.

The good news is, it is unlikely to have bacterial contamonation because of the high fat content, so should be safe. Spread a little on a piece of hat toast and taste it to make sure it is not rancid. It would be a pity to ruin your Christmas baking with slightly "off" butter.

If it is OK, use it for spice cookies, fruitcake or one of the stronger flavored cookies, and injdulge in some very fresh for the sprotz or butter cookies.

my husband grabbed some opened canola oil a half filled gallon plastic container and sauteed a bunch of peppers, mushrooms and onions in. The problem is it was sitting on the floor of the pantry for a year. Is it still good to use. I do not know if I smelt funny oil or the strong smell of onions and peppers. what can we do about the cooked vegetables if, even he, suspects he did make a mistake (although not likely). Can we boil the three pounds of each vegetable and then re fry them since he only crisp them up in the oil. I might be wrong but the oil did not smell bad but left a greasy taste in my mouth. Help! please

I suggest you heat a small amount of fresh oil in a pan without the onions and peppers and smell it- as mentioned above, if "off" you will smell it as it first heats up. If it is OK why rinse the pappers? If it is not OK, you can try rinsing, but what are you doing then? If freezing, the vegetables need to be cooked after rinsing and before freezing.

I suggest you heat a small amount of fresh oil in a pan without the onions and peppers and smell it- as mentioned above, if "off" you will smell it as it first heats up. If it is OK why rinse or simmer the pappers? If it is not OK, you can try rinsing, but what are you doing then? If freezing, the vegetables don't need to be re-cooked after simmering, you lose a good bit of flavor.
what is better for deep frying peanut or cotton seed oil

Peanut oil can be heated to a higher tempersture without breaking down or smoking, so it is recommended for frying.

Also, since many pesticides tend to favor the seed and collect there, they remain in the seed oil when it is pressed. Pesticide residuals from non-food crops such as cotton can be avoided by avoiding the oils extracted from these seeds. I encourage people to use oils extracted from food crops, and perswonally stick with organic oils for salads and cooking - I don't do deep frying much anymare, but when I do I use peanut oil.

I have some peanut oil tht has never been opened or used. The official expiration was a year ago. Seeing that it was never opened and has been stored in a cool dark place, do you think it will be ok?

Most likely. Open. heat some and stand over the pan to smell. Smells clean and fresh? OK.
Dr.Piyush k gandhi
Hi ,
Please tell me the reaction when ghee(clarigied butter) is heated with water. Also tell reason why bubbles produced in during heating with water.
please reply.

Thank you.


To make ghee, you warm butter to allow the fats to separate from the dairy solids and also to cook off the water. Removing these solids and cooking off the water helps the ghee or butter oil to keep longer, especially at room temperatures, without oxidizing. The bubbles when you heat it with water are most likely steam bubbles from the water. Why are you heating the ghee with water, anyway?
Roger Rabago
The Knights of Columbus, at our Church have a fish fry every Friday during Lent. We have been using an oil derived from soy with citric acids added. After each fish fry we let the oil cool overnight, filter it the next day, and store it in our walk-in cooler, 40 degrees. We use the oil 2 or 3 times and then start again with new oil.
Someone has recomended that we use cotton seed oil. Can we use the same procedures above?
Which is better?
With thanks

Roger, stick with the soy oil. soy is a food crop and has less insectisides, etc to start with. Only peanut oil is better for frying. You are using the right cleaning procedure.

I had a small container of vegetable oil leftover from pan frying potatoes, that was in the fridge for a year. I didn't bother testing it or anything, so it went right in the garbage. I'm curious about if it's possible for a creepy crawly to form in the oil if it sits too long? Weird question, I know!

Usually. nothing grows in the oil, it is just chemical changes.
I'm wondering what the best way too cool oil is.
I'm going to be working at a street fair this summer. We'll be deep frying in oil. The temperature will be about 350 and the oil should probably be closer to 100 to store in the plastic container that it came in.
Have any suggestions?

Be VERY CAREFUL handling hot oil- try your pouring techniques outside with regular water and check out how HEAVY those hot containers are. This is why a lot of commercial equipment has spigots.

Ice and lots of it surrounding a metal container into which you strain the hot oil is one option.

Margaret Kaltenbach

Peanut oil
Where can I buy peanut oil by the gallon?

Any warehouse store (Costco, etc), any restaurant food supply store/ wholesale grocer, and some regular groceroes carry it. Most regular groceries can special order it.
Remove rancid odor
How to remove rancid odor in the coconut oil which have been fermented?

The rancid odor is a sign the oil is not good for eating anymore. I have no suggestions how to remove it, but do suggest you don't eat it.
Mary Leckie
I was wondering if it's safe to reuse canola oil after deep frying chicken wings or should oil be discarded after each use?

Mary, I have discussed this at length in the questions above, so will not repeat- please read the thread.
Can a used oil back its usual color? like when the color of the used oil is black brown.
Can a used oil back its usual color? like when the color of the used oil is black brown.

I have never seen this, but no, you can't undo the changes caused by heating, they are chemkical changs.