Proper disposal of used cooking oil/fat/grease

[LindaK]

I've decided to join the deep frying club too, so this is all helpful information. But I still have a few questions about reusing oil.

It sounds like filtering is imperative. what do you use--cheesecloth? coffee filters?

what type of container do you use, or does it not matter? can i recycle a milk jug, for example?

do you store your oil at room temp, in the fridge, or in the freezer?

[gfweb]

I store mine strained, but not filtered, at room temp in a big plastic jug. I've not had problems, but I can't say that I know that this is the best method. It would be a good study for a someone with access to a lab. What changes exactly make for "bad" oil? What foods make oil spoil? How many uses with various foods until the oil is no good. How much time can the stuff sit at room temp etc etc. Mc Donald's has the data I'm sure.

[sparrowgrass]

I reuse my oil a couple times, til it smells funny. One thing that makes it easier to filter is to do it while it is still hot. Don't be stupid and burn your fingers off -- let it cool a while, but hot oil goes thru the filter much faster. I use a coffee filter, usually, set in a big colander over a bowl.

Edited January 14, 2011 by sparrowgrass (log)

[nakji]

what type of container do you use, or does it not matter?

I use a stainless steel cup with lid. I think you can get ones with a mesh strainer, but I didn't bother; I just set one over the top when I'm emptying my wok. It's convenient, because I can tip in hot oil. Since my kitchen is cool, I keep it on the counter, so I dip oil from it into the wok as needed.

[Anonymous Modernist 301]

I have read the section in book II regarding deep frying. My wife and I enjoy home cooked deep fried foods on occasion but we have one problem and that is we don‚’t have a desire to deep fry more than one a twice a month. Do you have any data on how to store the oil after its initial use? How long will it stay viable, what are the methods for keeping it viable longer, etc.? For the number of times we wish to deep fry, it is wasteful to use the fat once notwithstanding the break-in period. Can anyone offer specific data to this effect?

Glenn House

[Anonymous Modernist 10]

Glenn House said:

I have read the section in book II regarding deep frying. My wife and I enjoy home cooked deep fried foods on occasion but we have one problem and that is we don‚’t have a desire to deep fry more than one a twice a month. Do you have any data on how to store the oil after its initial use? How long will it stay viable, what are the methods for keeping it viable longer, etc.? For the number of times we wish to deep fry, it is wasteful to use the fat once notwithstanding the break-in period. Can anyone offer specific data to this effect?

Glenn House

Hi Glenn,

Here are a few tips for keeping frying oil once you've used it.

Filter out all of the solids. They will flavor the oil and turn it rancid more quickly.

Because oils will oxidize in light, wrap your container in aluminum foil.

A hermetic seal is best. If you have a vacuum sealer, use it! If your vacuum sealer doesn't seal liquids, freeze the oil and then seal it.

The colder the oil is, the longer it will keep. This is why some people prefer to keep their oils in the fridge.

If all else fails, smell it! Sometimes your nose is the best judge.

[Anonymous Modernist 2565]

Hi there, I also have a question regarding this chapter, i hope you can help

for a while now i have been adding methylcellulose to my batter for deep frying (at 1% of total weight), with the theory that the methylcel will "gel" in the heat of the oil, thus more effectively reducing the amount of oil the batter absorbs by forming a protective barrier. Obviously melting after it cools enough to eat, and therefore not effecting the final texture or flavour.

this seems to have been working for me for a long time (although, until i read this chapter, I assumed it was for entirely different reasons lol)

now my question is, does this actually have any scientific basis? if so, (and this may require some testing beyond my capabilities) does it have a similar, or better effect than the egg white and calcium additions that you recommended?

also, you mentioned there are many speciality blends of salts, gels and gums used for these purposes, is methylcel one of those ingredients?

What a happy accident

Regards,

Chefzilla.

[Anonymous Modernist 10]

Chefzilla said:

Hi there, I also have a question regarding this chapter, i hope you can help

for a while now i have been adding methylcellulose to my batter for deep frying (at 1% of total weight), with the theory that the methylcel will "gel" in the heat of the oil, thus more effectively reducing the amount of oil the batter absorbs by forming a protective barrier. Obviously melting after it cools enough to eat, and therefore not effecting the final texture or flavour.

this seems to have been working for me for a long time (although, until i read this chapter, I assumed it was for entirely different reasons lol)

now my question is, does this actually have any scientific basis? if so, (and this may require some testing beyond my capabilities) does it have a similar, or better effect than the egg white and calcium additions that you recommended?

also, you mentioned there are many speciality blends of salts, gels and gums used for these purposes, is methylcel one of those ingredients?

What a happy accident

Regards,

Chefzilla.

Methylcellulose has two functions in batter:

1. We like to siphon our batter. Methylcellulose is a good stabilzer/agent in foams, which is important because when we aerate batter, the coding is actually much lighter and delicate.

2. It gels upon heating providing structure to the batter beyond the egg/starch componants that typically give batter its body. We have noticed in some tests, not done on batters but on fried chips, that have been coated with a methethylcellulose slurry that thet will absorb less oil. This MAY be because the porous vacules or air pockets have been filled with that gel, which forms a barrier to oil absorbtion.

Does that answer your question? What else are you interested in?

[Anonymous Modernist 2565]

yes, that answers my question, thanks very much Max

thats a very broad question, im interested in everything food science!

currently researching animal rearing, and its effects on final product quality if you know much about that, or have any links?

have loads of info on final feeding and pre-slaughter stress etc so far, just gotta find more on selective breedingto birth to pre-final few months.

[TdeV]

My mum used to store the deep fry pot (with oil) on a shelf in the kitchen, and then reuse it. I now imagine that I would find the taste of the old oil off-putting.

 

I can't remember when I last did any deep frying.

 

Also, of course, deep fat frying is probably unhealthy. Are people satisfied with the "air fryer" alternatives?

[JoNorvelleWalker]

If you want my honest answer:  I spill it on the counter.  Some goes on the floor.

 

[heidih]

Serioyus Eats addrressed the issue the other day probably for Passover frying. .   Hopefully our master fry folki like @Shelby and @HungryChris  If done properly your food should be crisp and not oily.  If you measure before and af6ter there shoud be only a slight difference,    https://www.seriouseats.com/2019/04/how-to-dispose-of-cooking-oil.html

[Tri2Cook]

I bring an empty large (16 liter) oil container home from work. I dump the cooled oil in it, put the lid on and store it on the stairs to the attic (which are behind a door located in the kitchen). When it's full, I take it to work and leave it with the ones from work to be disposed of by whoever picks all that up and I take another empty home to start the process again. But I realize that's not an option for everybody.

[liuzhou]

It depends on what has been deep fried in the oil. Oil for chips/fries, I will happily, filter, store in a covered metal pot which sits on the counter and re-use once or even twice.

 

Oil used for fish or anything spicy, I dispose of after one use. I have a 5-litre old oil bottle under the sink and used oil is put there until full, then properly disposed of.

[kayb]

I'm with @liuzhou. I have filtered (through cheesecloth or paper towels) used oil as long as it's not used for fish, and kept it in the fridge and reused three or four times, maybe more. Fish-frying oil gets dumped in an empty glass jar and tossed in the trash.

 

When I was a kid, we lived out in the country and, to minimize trips to the dump, burned a lot of our trash in a big 55-gallon barrel. We'd just pour fish oil, or oil that had gone off after several uses) on that and burn away.

[Ann_T]

I will reuse oil that has been used for fries only.     And just once or twice before disposing of it.  

 

I can dispose of cooking in in a milk carton in with out weekly "organics/compost" pick up. 

 

[btbyrd]

Brand new oil is actually not as good as "older" fry oil, as slightly heat-damaged lipids are better at making physical contact with the surface of food (I believe for ionic reasons, if I recall my Dave Arnold correctly). At any rate, brand new fry oil isn't ideal for producing a brown crust as easily. That's not why I save my oil... but it's a good story to tell to myself while I'm filtering the oil and putting it back in the jar. I "backslop" old oil back into the main container, but only if it's been used to fry clean-tasting foods like potatoes. If fish or brassicas or some other such thing got fried in there, I end up disposing it.

 

I use high oleic sunflower oil for most of my deep frying needs. It hits the right balance between having a healthy lipid profile, high smoke point, neutral flavor, and relatively low cost. There's probably something better out there, but I haven't had the time (or the need) to explore the options in depth. Most industrial seed oils used for deep frying are a freaking nightmare on your body from a health perspective (though that's a matter for another forum). I also like to use lard and tallow from pastured pigs and cows. For different reasons, and for different applications.

 

The flavor of french fries made in beef tallow is superb. Apparently, if Steingarten is to be believed, a mixture of half horse fat and half beef fat tastes even better. But that beef fat french fry flavor is the core of the OG McDonald's french fry -- the Original Platonic Form of the French Fry in the American imagination. That was before the damned vegetarians and their health-nut disciples forced an industry-wide switch over from saturated animal fats to hydrogenated vegetable oils. Stupid jerks. How'd that work out for us? Want to ban trans-fats now? Guess who brought those into our dietary system, jerks!!! But I digress....

Lard also makes good french fries. Great onion rings. But it's the bee's knees for fried chicken. Chicken fried in lard? Yes. Throw in some fresh bacon fat and some rendered fatty funk from a country ham? Hell yes. Lard has a lot of monounsaturated fats compared to tallow, which makes it much more fragile from a heat stability standpoint. You can't reuse it over and over like you can with tallow. But if you're making fancy fried chicken for family supper on a Sunday afternoon? Boy howdy, get you some lard and get frying. You may well have to throw the fat away afterwards... but to think of the spent fat as "waste" is to have missed the magical work it did for you.

Edited April 23, 2019 by btbyrd (log)

[Duvel]

1 hour ago, btbyrd said:

as slightly heat-damaged lipids are better at making physical contact with the surface of food (I believe for ionic reasons, if I recall my Dave Arnold correctly).

 

If you have a reference for this it would be highly appreciated !

[btbyrd]

It was on one of the back episodes of Cooking Issues. But the issue of polarity impacting the consistency of fried foods is well documented at the commercial level. Here's an article on monitoring polar compounds in fryer oil. A relevant nugget:

 

"Total Polar Compounds affect the consistency of deep frying by increasing the release of water and the absorption of fats into the product. French fries, for instance, will brown but will be hollow because the moisture has been released too quickly."

 

 

[KennethT]

3 minutes ago, Duvel said:

 

If you have a reference for this it would be highly appreciated !

I don't know the exact chemistry, but from what I understand of it, used oil has more "soaps" which allow better contact between the watery food and the oil.  Shirley Corriher had a whole thing about it - and I believe it's in McGee as well.

 

But on that topic, it turns out that you really don't need that much old oil...  I've always heard it recommended that when you dispose of old oil that's been used a few times, to save a few tablespoons of it and add it to the new oil... evidently, that's really all the soap you need...

[Duvel]

1 minute ago, KennethT said:

don't know the exact chemistry, but from what I understand of it, used oil has more "soaps" which allow better contact between the watery food and the oil.  Shirley Corriher had a whole thing about it - and I believe it's in McGee as well

 

That sounds meaningful. I’ll check that, but if anyone has a bibliographic reference available I’ll be grateful ...

[btbyrd]

There's some surface activity stuff going on there too, for sure. I'll go reread Shirley Corriher, as it's been a while. She doesn't get nearly enough play! I don't know who McGee's agent is... but maybe she should switch over. 🙂 

[btbyrd]

Okay... some nuggets from Shirley. Cookwise is an AWESOME book, and her section on frying is fantastic.

 

"New crops like high oleic sunflower oil and low linolenic soybean oil maximize single double bonds and minmize double and triple double bonds, making for more stable and healthful oils. The more healthful unsaturated fats can be used if the oil is not going to be re-used. Considerations like flavor and smoke point may be more important than saturation." (158)

 

That's basically why I keep HO sunflower oil and tallow on hand. Tallow is super stable (and not terrible for you, if your cow didn't spend the last two months of its life in a concentration camp). But for a vegetable-based option, HO sunflower oil is pretty dang good.

 

She does not recommend re-using fry-oil from home because it does not contain the common additives (like anti-oxidants) that help keep commercial fryer oil from breaking down. I don't fry that hot and I use relatively stable fats, so I don't know that this nugget applies across the board. You can always add some mixed tocopherols to your oil if you want to, and create your own "commercial" fry oil.

 

Commercial fry oils contain trace amounts of certain silicones, which form a film on the surface of the oil, preventing direct contact with oxygen in the air (and thereby limiting oxidative rancidity).

 

Solid vegetable shortenings often contain emulsifiers like mono and diglycerides, which makes them good fats to use in cakes but lowers their smoke point and makes them bad for higher temp frying.

 

I couldn't find anything on polarity and browning, but KennethT is right on the money that you don't need to add much "old" oil to fresh oil to reap the benefits of slightly damaged fry fats. The key is that the damage is *slight*. You don't want to slop back a bunch of burned up fishy-smelling rancid garbage oil into your jug. That's not going to be good for anyone.

Edited April 23, 2019 by btbyrd (log)

[Duvel]

Thanks. If that number behind your citation refers to an original article that would be the one I’d be interested in. Nevertheless, I’ll check tomorrow PubMed and its relatives ...

 

5 minutes ago, btbyrd said:

which form a film on the surface of the oil, preventing direct contact with oxygen in the air (and thereby limiting oxidative rancidity).

 

Sorry, but definitely not.

[btbyrd]

2 minutes ago, Duvel said:

 

Sorry, but definitely not.

 

Meh?