# How do I keep oil from going bad? **URL:** \ **Category:** Cafe Society\ **Created:** [July 11, 2006, 3:15pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032 "2006-07-11T15:15:01Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![tdn](https://avatars.discourse-cdn.com/v4/letter/t/94ad74/32.png) [@tdn](https://boards.straightdope.com/u/tdn)\ **Post date:** [July 11, 2006, 3:15pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/1 "2006-07-11T15:15:01Z")
I tend to buy cheap cooking oils. Not that I have cheap tastes, mind you. I’d love to spend a good $50 on olive oil. Thing is, though, I use so little oil when I cook that it goes rancid before I use much of it. I’m constantly throwing out 3/4 full bottles of canola, peanut, olive, and sesame oils. If I want to cook, let’s say, Chinese, I’ll have to buy a whole new bottle of peanut oil for the occasion because chances are the mostly full bottle I already have has already gone bad. Is there any way I can preserve a given bottle of oil for, say, more than a year? ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [July 11, 2006, 3:18pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/2 "2006-07-11T15:18:04Z")
> [@tdn](#): > > I tend to buy cheap cooking oils. Not that I have cheap tastes, mind you. I’d love to spend a good $50 on olive oil. > > Thing is, though, I use so little oil when I cook that it goes rancid before I use much of it. I’m constantly throwing out 3/4 full bottles of canola, peanut, olive, and sesame oils. If I want to cook, let’s say, Chinese, I’ll have to buy a whole new bottle of peanut oil for the occasion because chances are the mostly full bottle I already have has already gone bad. > > Is there any way I can preserve a given bottle of oil for, say, more than a year? More than a year? Maybe. Do you refrigerate them? While some oils (like olive) will solidify in the fridge, I don’t find that much of a problem. I do store them in wide-mouthed jars, though, so I can scoop out what I need with a spoon. I go through mine within a year, though, so I don’t know if they’ll last longer than that. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [July 11, 2006, 3:19pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/3 "2006-07-11T15:19:22Z")
GAH! I am _so_ sorry I quoted the OP in the first reply. That’s one of my pet peeves, and it was purely accidental. ---
**Author:** ![tdn](https://avatars.discourse-cdn.com/v4/letter/t/94ad74/32.png) [@tdn](https://boards.straightdope.com/u/tdn)\ **Post date:** [July 11, 2006, 3:23pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/4 "2006-07-11T15:23:21Z")
> [@WhyNot](#): > > More than a year? Maybe. I’d settle for two months, actually. Olive oil seems like the least of my worries. Peanut and sesame seem to be the worst. I understand that rancidity is more of a problem than bacteria, and it’s caused by oxidation. I keep things tightly capped, so I’m not sure why they go bad so fast. ---
**Author:** ![don\_t\_ask](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)\ **Post date:** [July 11, 2006, 3:36pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/5 "2006-07-11T15:36:12Z")
I’m sorry you brought [this up](http://www.survival-center.com/foodfaq/ff10-fat.htm) I will have to rethink my oil usage. ---
**Author:** ![Cub\_Mistress](https://avatars.discourse-cdn.com/v4/letter/c/ea666f/32.png) [@Cub\_Mistress](https://boards.straightdope.com/u/Cub_Mistress)\ **Post date:** [July 11, 2006, 3:48pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/6 "2006-07-11T15:48:31Z")
I would refrigerate it, maybe decanted into a smaller, tightly closed container. ---
**Author:** ![bouv](https://avatars.discourse-cdn.com/v4/letter/b/bc8723/32.png) [@bouv](https://boards.straightdope.com/u/bouv)\ **Post date:** [July 11, 2006, 3:50pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/7 "2006-07-11T15:50:00Z")
The best you can do is keep a tight lid on it and keep it in the fridge. I don’t think peanut or sesame oil solidify at that temperature, but I’m not sure. You could also put a small amount in a seperate container and then freeze the rest, and just make sure to take out some more when you get low on the thawed amount. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [July 11, 2006, 3:59pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/8 "2006-07-11T15:59:05Z")
> [@tdn](#): > > I’d settle for two months, actually. > > Olive oil seems like the least of my worries. Peanut and sesame seem to be the worst. > > I understand that rancidity is more of a problem than bacteria, and it’s caused by oxidation. I keep things tightly capped, so I’m not sure why they go bad so fast. Sesame is tricky, but peanut oil should last a while. Certainly more than two months, even in a clear plastic bottle in your pantry. Are they exposed to light and fluctuating or high temperatures? That can make them go rancid sooner. ---
**Author:** ![tdn](https://avatars.discourse-cdn.com/v4/letter/t/94ad74/32.png) [@tdn](https://boards.straightdope.com/u/tdn)\ **Post date:** [July 11, 2006, 6:18pm UTC](https://boards.straightdope.com/t/how-do-i-keep-oil-from-going-bad/364032/9 "2006-07-11T18:18:35Z")
> [@WhyNot](#): > > Are they exposed to light and fluctuating or high temperatures? That can make them go rancid sooner. Not light, but my kitchen is little bigger than a walk-in closet. When I cook, it heats up pretty fast.