Uses for vegetable oil in garden

Cooking oil is essential in home kitchens and commercial kitchens alike because it is used in a wide variety of cooking. In both situations, the one doing the cooking must deal with the issue of disposing or recycling the used cooking oil.

In homes, simply disposing of cooking oils down the drain is a bad idea because the oil will harden in the drain and cause a clog. In commercial kitchens, the large volume of cooking oil must be dealt with using proper equipment so that the used cooking oil is deposited into a holding tank.

It is very important to ensure that used cooking oil is collected and recycled properly to help protect the natural environment. Cooking oil that is allowed to enter the natural environment can cause problems, especially if it enters the municipal sewer system.

For those that cook at home, simply put your used cooking oil in a mason jar or something similar to avoid washing it down the drain. If you run a commercial kitchen, then you should work with a professional like Mahoney Environmental to help manage your used cooking oil and provide cooking oil pickup and recycling services.

Collecting the used cooking oil is only half the battle. The next step is figuring out what to do with the used oil. Fortunately, used cooking oil can be repurposed in a number of different ways, from being used as a lubricant in your home to being made into biodiesel to fuel diesel engines.

The following are 15 different uses for used cooking oil. Many of these uses are perfect for putting your used cooking oil at home to good use while advanced level reuse requires a professional to recycle and re-purpose the oil.

  1. Household lubricant: Used cooking oil is an effective lubricant that can be used for many things around the house from squeaking hinges to troublesome locks. Used cooking oil also helps prevent rust on metal surfaces and objects such as tools.
  2. Key lock lubricant: If your key regularly sticks in the locks in your home, spreading some cooking oil on your key will prevent it from sticking.
  3. Lamp oil: If you have an oil lamp in your home, you can use your used cooking oil to fuel the lamp.
  4. Furniture polish and conditioner: If you have wood furniture in your home that looks dull or scratched, used cooking oil can be used to polish and restore the look of the wood. Make a mixture that is equal parts used cooking oil and vinegar and use it to polish your wood furniture.
  5. Leather preservative: Used cooking oil can also be used to soften and preserve your leather furniture.
  6. Rattan and wicker furniture protector: Rattan and wicker furniture is vulnerable to cracking. Rubbing some used cooking oil onto the surface of rattan and wicker furniture with a soft cloth will help keep it protected from cracks.
  7. Removing paint from your hands: Paint is one of the hardest things to wash off if it gets on your hands. You can remove paint from your hands easier with used oil. Rub some used oil on your hands and let it sit for 5 minutes, then wash your hands and the paint will come off.
  8. Soap making: Lye soaps can be made using used cooking oils. There are instructions available online as well as books about how to make lye soap if you are interested in soap making.
  9. Hair moisturizer: Used vegetable oil can by used to condition and moisturize your hair. Heat up half a cup of oil so it is about room temperature and massage it into your hair. Shampoo and rinse your hair to remove the oil.
  10. Pot and pan protector: Rubbing some used cooking oil on the surface of new pots and pans can help keep them protected. Wash your new pots and pans before you use them and rub some used oil on the surface.
  11. Non-stick gardening tools: Soil and grass can stick to gardening tools like shovels, trowels, and lawnmower blades. Coating these tools with used cooking oil will prevent grass and dirt from sticking to them.
  12. Car cleaner: Used cooking oil can be used to remove tough dirt and debris from any surface of your car including the brakes and the body. Put a little bit of cooking oil on a rag or paper towel and wipe the affected areas. Used cooking oil can effectively remove dirt, grime, pollen, bugs, and other gunk.
  13. Composting: If you have a compost pile, adding used vegetable oil to the pile can help. Adding small amounts of used vegetable oil will feed the worms that help with the composting process. Make sure you only use vegetable oil because animal-based oils will attract nuisance animals and cause pathogens to form.
  14. Animal feed: Used cooking oil can be used as animal feed in a number of different ways. You can drizzle some used oil on the food for your dog or cat which will improve the taste for them and keep their coats shiny. You can also mix some oil in with the bird seed in your bird feeder.
  15. Biodiesel fuel: Used cooking oil can be used to produce biodiesel fuel once it has been processed. There are kits available that can help you convert used cooking oil into biodiesel fuel, but this is best done by professionals who can process the oil for biodiesel production.

There are so many effective uses for used fryer oil, whether it is animal-based or vegetable oil, which makes it one of the most reusable products in your home. The one thing you should never do with used cooking oil is dispose of it by putting it in the trash or washing it down the drain. In home kitchens, you can make this adjustment very easily by saving your cooking oil in a jar and using it for these various alternative uses.

If you run a commercial kitchen, you need to have an entire oil management system in place to manage to use of fresh cooking oil and the removal of used cooking oil. At Mahoney Environmental, our professionals can design and install cooking oil systems that will streamline or automate the handling of the cooking oil.

We also offer used cooking oil pickup and recycling services to regularly remove the used cooking oil from your establishment and take it back to our facility where it can be processed and recycled as biodiesel fuel and animal feed.

Composting cooking oil

Can you compost cooking oil? This is a common composting query that a simple google search doesn’t seem to provide an adequate answer to. And it’s because the answer is not really that straight forward.

All organic matter is compostable, so technically the answer is yes. However, some waste is more complex than other waste and this effects the time it takes to break down. Oil falls into this ‘more complex’ category and so will take longer to break down than say your simple fruit and veg. There are plenty of people who advise against composting oils on the basis that the average home compost pile doesn’t get hot enough to break down more complex materials like oil. This will lead to rot, attracting rodents, smells, will reduce the air flow through your compost heap, displace water and ultimately threaten to kill the compost.

While these folk have a point, I don’t entirely agree. I think the real question is how much you can add and ensure your compost remains healthy. If you add only enough that your compost pile can actively absorb it into the composting process, it will be fine. How you strike the right amount is more difficult to answer. As is always the case with composting, it’s a case of balance and of trial and error.

My advice is to add small amounts to the compost pile comparative to other food items. Be conservative and push it a little further only when you’re confident. If you have a worm farm, the same rule applies. For my small urban worm farm, I’ll throw in paper towel that I’ve used to wipe out fry pans with success as well as other scraps with small amounts of oil involved. But I don’t throw in run off from the fry pan following deep or shallow frying – I think that would overwhelm the worms. I also make sure I dig the scraps through so it’s well integrated into the farm.

If you have left over food cooked in oil (with the exception of meat), they can be composted using the same rule: if you don’t think the oil factor is going to upset the balance, go for it!

The thing is, if you run a small family compost pile, this isn’t going to solve your cooking oil problem. So what else can you do to ensure it doesn’t go to landfill?

Reusing or Recycling Cooking Oil

  • Use less

This isn’t always practical advice, but I do find it helpful to be mindful of how much oil I actually need for my cooking. Although I don’t tend to strictly stick to measurements when cooking, I do find I use less oil when I measure it out. Or, when you do have an option, you could choose to shallow fry rather than deep fry; steam rather than fry.

  • Reuse

You can recycle large quantities of cooking oil for reuse in the kitchen. Why not strain and strain and store for future cooking use? This works for animal fats (bacon, beef) as well as plant-based fats (olive oil, sunflower oil). You will need to take care that the latter, however, does’t exceed its smoke point. This will make it unsuitable for re-use. Otherwise, strain through cheesecloth and store in an airtight container in the fridge.

  • Make Soap

I am yet to try it, but love the idea. Check this recipe out if you want to give it a go.

  • Give it to your animals

If you have an active dog, a small amount of oil added to your dog food will ensure a shiny coat and your dog will love it (and don’t worry, he will work off the extra calories). Or Roll used solidified fat in bird seed and stuff it into an old stocking to hang out for the birds as a feeder.

  • Make biodiesel fuel

Some commercial users might want to consider recycling their cooking oil as biodiesel but this isn’t so practical for home cooks because you just won’t have the quanitities.

  • Curb-side and drop-off recycling.

Ask your local authorities for disposal options.

What not to do

Avoid putting any cooking oils down the drain or the toilet – it clogs drains and sewerage pipes and it pollutes waterways. If you can find an alternative use for your oil than sending it to landfill, that’s ideal. Of course, that’s not always the case. If you do put your oil into the rubbish, before you do, seal it in a container and place it in a reused plastic bag.

Learning to fry food as a college student is no small feat. Sadly, getting that food onto a plate and seasoning it perfectly is only half the battle. After finishing your exquisite meal, you often find yourself confronted with a pot or pan of used oil. What do you do?

The proper disposal of oil is an important waste concern. Cooking oil can block plumbing and piping, which allows for sewage backup into homes and businesses (ew). People assume that pairing the used oil with hot water and pouring it down the drain will suffice, but drains do not have a proper grease management system, and the problem continues to persist.

How do we stop this unsanitary phenomenon? Here are eight ways to get rid of that cooking oil through responsible and sustainable methods. Your drains and the environment will thank you.

1. Re-use it

The best way to dispose of used cooking oil is to, well, re-use it. If you use the oil for foods like vegetables or potatoes, the oil can be used again several times. Beware of cooking meat or fish repeatedly in oil, though. While it can be used for the same product two or three times, it’s best to make sure the oil is safe to cook with. Follow these steps to ensure safe oil every time.

2. Pour it out

Recycling sounds nice, but sometimes it’s just impossible to do. If you have to throw your oil out, do it the right way. Once the oil cools, pour it into a milk carton or an unrecyclable container and toss it out. Make sure the container is unbreakable and it is sealed tightly to prevents spills and leakages into your garbage can.

3. Freeze it

A good way to deal with oil, whether you plan on re-using it in the near future or throwing it out, is freezing it. Once the oil cools, pour the oil into a tightly sealable container. Place it in the freezer, and done; it can be re-used at a later date and even makes for an easy way to get rid of otherwise pesky liquified oil.

4. Convert it into biodiesel

UnitedSoybeanBoard on Flickr

Say what? Believe it or not, leftover oil can be turned into biodiesel, which can be made from oils like vegetable oil or animal fat combined with an alcohol like methanol. It is a desirable substitute for petroleum because it is supposedly less damaging to the environment and emits less harmful greenhouse gases when turned into fuel for tractors, motorcycles, and more.

While you personally may not have enough cooking oil to do this, contacting your local restaurants to see if they participate in this awesome method of recycling is a great way to get rid of your unwanted grease and save the world at the same time.

5. Get someone else to recycle it

Even if your local restaurant doesn’t convert their used oil into biodiesel, there are still countless programs run by other restaurants, waste management companies, and the government that aid in the effort to reduce neglectful disposal of oil. Just search for your state or county and programs like Cease the Grease or this program from Brighton County which may be in action near you.

6. Compost it or use it to kill weeds

crabtree on unsplash

Vegetable oils, such as canola or olive oil, are compostable in small quantities. Oil can also be used to kill weeds; just place it in a spray bottle and spray those unruly nuisances away. It’s like killing two birds with one stone.

7. Mix it

If you really just want to throw your oil away, mix it with an absorbent material, like sawdust, cat litter, or flour, until the consistency is thick enough to easily throw away. Now you won’t have to worry about oil leaking through garbage bags or spilling all over the place.

8. Try the Fat Trapper System

The Fat Trapper System is a plastic container holding an aluminum foil bag created just for the oil dilemma so many of us face. It effectively holds grease and oil in an odor-free, entirely sanitary contraption. You just fold the bag and throw it away once it’s full. Get your fat trapper system here for mess-free oil disposal every single time.

While it may be easy to pour your used oil down the drain, it is definitely not the safest. So long as you take precautions when re-using, recycling, or throwing away your oil, you should never have to face the consequences any careless actions can create. Don’t let your efforts in preserving the environment go down the drain.

Cooking oil: Down the drain or in the compost bin?

Verdict: Never pour the oil down the sink. The best course of action is to check out one of the local grease recycling programs like SFGreasecycle, which tries to turn residential fats, oil and grease into biofuel ( and EBMUD’s residential cooking oil and grease drop-off locations (

Robert Reed, spokesman for Recology, the company that processes household waste in San Francisco, suggests collecting fat from frying bacon or hamburgers into an empty soup or coffee can. “It wouldn’t make sense to make a trip and burn gasoline just to take in a small amount of household cooking oil, but saving it until you have a significant quantity and taking it in when you are going to be in the vicinity of an authorized drop-off would be efficient and allow the oil to be processed into biodiesel,” Reed says.

Alternatively, a few Bay Area municipalities, including San Francisco among them, can process small quantities – a tablespoon or three per household – of cooking oil in compost. Hoover recommends mixing the oil with something that will absorb it, like food-soiled paper or leaves, before putting it in the green bin.

Have a eco-dilemma for the Green Scale? Send it to [email protected]

Can I Compost Fats and Oils?

(From the Leftover food category | )

No, you shouldn’t compost fats and oils.

The benefit of adding waste fats and oils to a compost heap are vastly outweighed by the potential problems. Not only can they attract rodents and other undesirable creatures to your compost heap, they can cause problems for the composting process: the oils can form water-resistant barriers around other material, displace water and reduce air flow in a heap, thus slowing down the composting process.

A tiny smear of butter or grease on a piece of kitchen roll or a carrot won’t be a huge problem for a compost heap but more than that will start to cause problems.

Fats that are solid at room temperature can be reused to make bird feeders for the garden.

Large quantities of used vegetable oil can be recycled – your local council should be able to advise if it is possible in your area.

Waste fats should NOT be poured down the sink – they can clog pipes and sewers, especially those solid at cooler temperatures.

Can I compost vegetable oil?

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How to Properly Dispose of Grease & Cooking Oil

Deep-frying your holiday turkey? Browning your Brussels sprouts in bacon grease? While cooking oil and grease add flavor to any meal, they can make a real mess in your kitchen when it comes to disposal, especially during the holidays. Make sure you know what to do with oil after cooking, because incorrectly disposing of grease and oil can have expensive consequences, such as emergency holiday calls to a plumber.

Keep reading to learn more about kitchen grease disposal and what not to do with used cooking oil.

The Best Way to Dispose of Cooking Oil and Grease

The right way to dispose of grease is simple; throw it in your trash can. Follow these steps to avoid pouring hot grease directly in your garbage:

  • Let the oil or grease cool and solidify.
  • Once cool and solid, scrape the grease into a container that can be thrown away.
  • When your container is full, place it in a plastic bag to prevent leakage and then throw it in the garbage.

Once you’re rid of the majority of the grease, use a paper towel to wipe down all pots, pans and dishes that came into contact with the oil before rinsing them in the sink. Even small amounts of leftover grease are dangerous to your plumbing because it will build up over time.

“Keep in mind that grease in drains, combined with food scraps from big meal preparation, is what makes our phones ring off the hook the day after Thanksgiving. That’s why it’s our busiest day of the year.”

Paul Abrams | Public Relations Director, Roto-Rooter Services Co.

How to Recycle Cooking Oil

1. Reuse Your Cooking Oil

As long as it has been used correctly and not heated past its smoke point, you can take steps to reuse your oil and fats. To reuse cooking oil:

  • Strain the semi-warm oil using cheesecloth, paper towels or coffee filters to remove any food particles.
  • Store in an air tight container in the fridge, freezer or other cool dark place.
  • Test the cooking oil before using by smelling it to make sure it’s not rancid.

You can reuse oil for deep frying, pan frying, sautéing and baking. After a few uses or when the oil goes bad, be sure to properly dispose of the oil in the trash can, as instructed above.

2. Find a Local Collection Site

Some municipalities collect used cooking oil for recycling. Use Earth911’s recycling locator to find a location near you. By using this option for kitchen grease disposal, you will keep your oil out of the landfill and turn it into a form of alternative energy, like biodiesel.

To recycle your oil:

  • Strain the oil to remove food particles.
  • Store in sealable container.
  • Deliver to your local collection site.

When you are recycling through a collection facility, you can mix different kinds of oils and fats in one container unless your collection site tells you differently, and you do not need to refrigerate the collection container.

How Not to Dispose of Cooking Oil

The trash can is the right way to dispose of cooking oil, but people often dispose of grease and cooking oil in other ways that are not advisable. Don’t get rid of grease using any of these methods:

Source: Roto-Rooter

1. Don’t Pour Oil Down the Drain

Pouring oil down the drain or toilet causes clogs in your home plumbing system and contributes to larger clogs in the municipal lines that can cause thousands of dollars’ worth of damage.

Oil and grease may be liquid when hot but will cool in your pipes, congealing and gathering other oil particles in the pipes. As the grease collection grows, it will prevent water from flowing through and causing it to back up into your kitchen and bathroom.

“Never pour cooking oil or grease down a drain. Hot cooking oil will solidify inside the drainpipe just like candle wax, which gradually decreases the diameter of the pipe with a greasy buildup until the pipe stops draining altogether.”

Paul Abrams | Public Relations Director, Roto-Rooter Services Co.

What if Grease Does Go Down the Drain?

Accidents do happen when it comes to kitchen grease disposal, especially when you have a bunch of relatives trying to help you tidy up after a holiday meal.

If grease or cooking oil does make its way into your sink, take immediate action with these tips from Roto-Rooter:

  1. Pour baking soda and white vinegar down the drain to clear some of the grease away.
  2. Try an enzyme-based drain cleaner, like Roto-Rooter’s Pipe Shield, which helps neutralize grease in both metal and PVC pipes.

If your sink is still slow, use a plunger to further dislodge the grease clog. If none of these fixes work, you will need to call a plumber.

2. Do Not Pour Used Cooking Oil Outside

Throwing used cooking oil outside is not a disposal option. If you pour oil on the ground, it will eventually end up in the sewer system and cause clogs there.

Additionally, animal and vegetable-based oils and greases can cause issues for wildlife when left outside, according to the EPA.

3. Do Not Dispose of Cooking Oil in Your Compost Pile

While small amounts of vegetable-based oils in your compost may be fine, a large amount will cause issues with airflow and moisture, ruining your fertilizer.

Animal fats should be kept out of your compost pile because they will smell, attract vermin and cause other issues that could make your compost unhealthy. No matter the type of oil or grease you’re using, do not dispose of it in your compost pile.

Whether you’re cooking a holiday meal or frying up breakfast, be smart with excess grease by disposing of it properly in your trash can or recycling it for future uses. Unless you want to invite your local plumber over for dessert, avoid pouring oil down the drain.

For more holiday tips, check out these posts:

  • How to Get Organized Before the Holidays
  • Holiday Recycling Tips
  • How to Dispose of a Christmas Tree

Grease gumming up the reclamation facility in Akron. Photo: Stephanie York, City of Akron

You’ve probably been told by your parents, plumbers, and Home Ec teacher that you shouldn’t pour grease and oils down the drain. These substances might start as liquids at the drain, but quickly harden, either in your pipes restricting flow and clogging, or clumps that form fatbergs. Now what happens when instead of pouring a few tablespoons of oil down your sink, you pour thousands of gallons of oil directly into the sewers? What happens is a crippled treatment plant, emergency government spending, and some very angry cops. Below are three stories about illegal grease dumping, and what you should take away from them.

Orange, Connecticut

Currently someone is illegally dumping thousands of gallons of grease down manholes in Orange. Not only is this causing major problems with the sewage system, but it’s also costing the town thousands of dollars.

“We don’t even have any money for it in the budget because it’s something that doesn’t normally occur and is not supposed to be occurring,” said R. Scott Allen, administrator of the town’s Water Pollution Control Authority.

However, this isn’t just a restaurant’s actions, currently police suspect this is a fraudulent grease hauling service avoiding disposal costs by illegal dumping. To avoid being an accomplice, make sure to vet your service properly: check their reviews and ask for references.

Akron, Ohio

The city of Akron is currently asking for anyone to come forward about the illegal dumping of grease that has damaged its water reclamation facility. Reclamation facilities play a vital part in any city’s water system, keeping waste from entering both the water supply and contaminating the groundwater. Grease causes damage and takes a great deal of time to remove.

“If it’s gummed up, not working properly, that’s equipment that’s down. That’s equipment that we need to spend an awful lot of time cleaning it up and if you have got just a little bit of grease on your floor, you know how difficult it is to clean up. Well, imagine large amounts of grease in mechanical equipment,” said Vince Zampelli, the plant superintendent.

Currently it’s unclear whether this is the work of a grease removal service illegally dumping, you can see the damage it causes to the infrastructure of a city or town.

Washington, D.C.

The Georgetown restaurant Tackle Box finally closed its doors after three years of legal disputes and troubles with its landlord, neighbors, and even their chef. Among the landlord’s other concerns, they accused the restaurant of illegal grease dumping. According to the Washington City Paper:

The D.C. Department of Public Works issued a violation against Tackle Box in June 2012 for illegally dumping cooking oil and grease outside (as well as failing to maintain the alleyway and prevent a rodent problem). The violation came with a $5,000 fine.

Not only can illegal grease dumping hit a restaurant up with a hefty fine, it can destroy your credibility. Not only can this lead to a money-hemorrhaging legal battle, but also eroding your clients and reputation as a restaurant people want to attend.

We hope these articles from around the nation help you understand why you should never dump grease into the sewers. Your dumping will be noticed and there will be stiff fines leveled at you. If you need help properly disposing of grease from your restaurant, contact the Food Grease Trappers. We’ve got a sterling reputation – even when we’re up to our hips in grease.

How to dispose of olive oil

It is easy to clean your pans in the kitchen sink and pour the oil down the drain, however oils can build up in pipes and eventually clog your sewage system.
This can cause raw sewage to flow into homes and the environment, sending unhealthy pathogens through the air that can impact your health.

Here are some tips to dispose of oil to prevent fat build-up in your pipes.

Let it solidify

Most cooking oils, except canola oil, will solidify once left to cool. Allow the pan and oil to cool down before wiping with paper towel, ensuring any excess oil has been absorbed, then disposing of the towels in the rubbish bin.

Use a container

If using an oil that doesn’t harden, put it in a sealable container before putting it in the garbage. Similarly, if you’d like an easier clean-up with solid oils, pour oil into a container and leave in the fridge to harden before disposal.

Add to compost

Vegetable oils and olive oil are organic material and can be added to your compost pile along with other leaves, fruits and vegetable scraps. Too much oil however may kill or slow down some organic processes, so be sure to add small bits at a time and mix in thoroughly to the compost.


By using a recycling centre or teaming up with a local restaurant you can safely discard a large amount of excess fats or oils you have left over. Keep a re-sealable container within reach and pour in any leftover oil. Once the container is full, take it to the recycling centre and add it to their grease disposal bin.

Re-use the oil

Oils used for deep frying can be used several times if you follow a few guidelines. Don’t mix different types of oil or keep on the heat after you are done cooking – exposing oil to prolonged heat accelerates rancidity. Make sure the oil is clear of any batter or food that may be left in it. Ensure the oil is stored in a cool, dark place, and that when you’re cooking, the temperature is at least 190 degrees Celsius.
There are several ways to use up excess olive oil that don’t involve cooking. It can be used as a wood furniture polish, a lubricant for joints and hinges, help with stuck zippers, and can prevent streaks and corrosion on stainless steel and brass.

Here are some suggestions that will, hopefully, prevent the formation of future fatbergs.

One can’t help but feel terribly sorry for the eight employees of Thames Water in London who are working non-stop to clear away the enormous ‘fatberg’ currently clogging pipes beneath Whitechapel. While pipe blockages are a regular occurrence, this is the biggest yet – a whopping 145-ton mass the size of 11 double-decker buses (or a blue whale!), made from a strange combination of solidified cooking oil and wet wipes. “Yuck” is a serious understatement.

A giant 145-ton “fatberg” has been found in the tunnels under London:

— Slate (@Slate) September 14, 2017 This problem, however, goes to show that London residents – and, doubtless, many others around the world – persist in their cluelessness about how to dispose of these everyday products. We’ve written many times on TreeHugger about the perils of so-called disposable wipes; one could say we’re flush with posts on the topic. But cooking oil is one that has not been discussed in as much detail, so here we go with tips on how to use, reuse, and discard old oil.

Cooking oil should never be flushed down the toilet or poured into a sink, no matter how much hot water or soap chases it down.

COOK WISELY: Cooking oil takes on the flavor of whatever it has cooked, so try to cook like with like. Think, too, about the order in which you fry foods. Breaded items tend to leave a lot of residue, whereas vegetables (with or without batters) are much cleaner; cook in order of cleanest to messiest. If you’re frying meat like chicken, the fat will render during the frying process and mingle with the cooking oil, which can shorten its lifespan.

USE SOLID OILS: I make this statement from a disposal point of view. Cook with oils that solidify once they cool, such as coconut oil, lard, vegetable shortening, or bacon fat. These are easiest to dispose of, since you can scrape them into the garbage directly. (Read further about the environmental and ethical effects of different cooking oils here.) Of course, it’s harder to use these solid oils in the large quantities required for deep-frying, which leads to the next point …

USE LESS OIL: The main reason I don’t own a deep fryer is because I don’t want to deal with old cooking oil. It’s too much hassle, and strikes me as wasteful, not to mention unhealthy. When a recipe requires frying (like latkes or falafel), then I use much less oil than it calls for. Sure, the texture may not be perfect, but then I don’t have surplus kicking around and can look forward to the real thing at a restaurant sometime.

REUSE: You should reuse old oil as much as possible. Cool the oil, strain through cheesecloth to get rid of food bits, and store in a glass jar (or the original container) in a dark cupboard.

There is no limit to the number of times you can reuse old cooking oil, but you should watch for signs of degradation, such as a murky appearance, foam, or an odor that’s off.

MIX WITH NEW: Food52 says it’s possible to mix small quantities of old oil with new for better frying.

“As oil breaks down, the molecules become less hydrophobic, which means they can come in closer contact with the food; thus, frying can happen more efficiently! (We learned this, too, from Kenji at Serious Eats.) This is why you’ll hear that some people reserve old oil for mixing with new oil. At some point, however, used oil becomes so much less hydrophobic than in its original state that it enters the food too quickly, which leads to sog and grease.”

DISCARD WISELY: There are a few recommendations for disposing of old oil. You should see if your city or municipality accepts cooking oil for recycling. (This is what fast-food venues typically do, as old oil now has value as biofuel.)

If you cannot recycle or reuse, you can pour the old oil into a non-recyclable sealable container and dump in the trash. This is the official recommendation from Thames Water.

Personally, I dislike the idea of tossing oil in the trash. I prefer to dig a hole in a corner of the yard near the compost bin and pour it in. It’s cleaner, simpler, and really no different than sending it to a landfill.

We use cooking oil to prepare everything from Thanksgiving turkey to sauteed vegetables to salad dressing. But considering it poses havoc to drains and our sewage pipes, you want to avoid pouring it down the drain.

Cooking Oil Recycling Preparation

  1. Designate a container in your house for used cooking oil. Metal coffee cans or plastic butter containers work great, but make sure it’s labeled so no one accidentally drinks it. You don’t need to keep it refrigerated unless you want to reuse it.
  2. Keep filling the container with new oil each time you cook. Don’t worry about draining any fats or combining different types of oil, but try to remove any large pieces of meat or produce.
  3. Use our Recycling Locator to see if there is a recycling location for cooking oil in your area. They may only be available during the holiday season.
  4. If no option exists, call your local fire department to see if used oil is accepted.
  5. If recycling is not available in your community, seal your cooking oil container and dispose in the garbage.

Why Recycle Cooking Oil

  • If you pour greasy oil down the drain, it will solidify and eventually block your pipes or cause damage to your city’s sanitation pipes
  • Cooking oil can be refined into biofuel that burns clean in most diesel engines
  • If you own/work at a restaurant or have access to a large amount of cooking oil, you can get paid by commercial oil recyclers for the product

Find Recycling Guides for Other Materials

Frequent Cooking Oil Recycling Questions

There are a handful of curbside programs in the U.S. that accept cooking oil at the curb, but you’ll have to call for a special collection. If your community accepts used cooking oil, make sure you are putting it in an approved container. If your community doesn’t accept oil at the curb, there’s likely a drop-off spot or special collection set up between Thanksgiving and New Year’s to accommodate the extra cooking during the holidays. A simple internet or phone book search for cooking oil buyers will find you local companies that will collect and pay for used cooking oil. These companies only buy in bulk, though, so unless you work at a commercial kitchen, you likely will not qualify. The cooking oil recycling process depends on where the oil is sent. If it goes to a processor, the anaerobic digestion process will break down the oil and any other organic ingredients without oxygen into a gas that can be used as alternative energy. If it’s sent to a biodiesel plant, it is filtered and processed into fuel that can be burned in most diesel engines, like trucks. Yes, as well as butter. You also don’t need to worry about using separate containers for each type of oil. No, but pouring it down the drain could cost you some money in pipe repairs. In a recent study of nearly 36,000 sewer overflows in the U.S., 47 percent were caused by fat and oil clogs. You probably don’t want to pay for a plumber on Thanksgiving. As a rule of thumb, you want to keep non-organic material out of your compost pile. So, if you are using oil to cook pasta and vegetables, you could take the chance. Any fats and animal products are not going to break down at the temperature you generate in a home pile. Most curbside compost programs will ask that you exclude cooking oil. In this case, we’re talking about deep frying where you could use up to 5 gallons of oil per meal. While you can reuse oil one or two times, you’ll want to make sure to drain any extra products in the oil, refrigerate it in a container, refrain from mixing different types of oil and check that the oil doesn’t look cloudy or foamy when you’re ready to reuse.

Additional Reading

  • 5 Oils from Your Kitchen You Can Add to Your Beauty Routine: Why spend money on cosmetics when you can use leftover cooking oils?
  • Cheat Sheet: Biofuel: An overview of how cooking oils are converted into biodiesel and other fuels
  • Cooking Oil, Grease to Power London Neighborhood: One of the world’s largest cities has built a facility to process used oil into residential energy

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