Never. Down. The. Drain.
Do not pour leftover frying oil down the drain—this is not a suggestion, but a hard and fast rule that you need to follow in order to maintain the integrity of your pipes and sewer system. Seriously, don’t let a bad habit cost you big time down the road. With that said, properly disposing of leftover frying oil can be tricky, as it never quite seems like a convenient undertaking. In order to avoid sending it down the drain and clogging your pipes for the rest of eternity (gasp!), here are a few tips to make the most out of your frying oil, and the best ways to get rid of it when the time comes.
Try to Use Solid Oils
Cooking with oils that solidify when they cool to room temperature will make your life significantly easier. Shortening, lard, coconut oil, and bacon fat are all great options for this—simply allow the oil to cool and scrape it into the trash once it’s solidified. If you like, you can also freeze the leftover oil in small cubes and repurpose it for future cooking. Unfortunately, none of these oils are going to be your top pick for deep-frying, so this isn’t quite the one-size-fits-all solution that you were probably hoping for.
Strive to Use Less Oil and Reuse if Possible
It is no secret that deep-frying requires copious amounts of oil. If possible, try using a shallow pan, rather than a deep-fryer or Dutch oven, for frying foods like latkes or breaded chicken. This way, you’ll use less oil and generally simplify the frying process. Additionally, once the oil has come back to room temperature, you can always send it through a strainer to fish out remaining fried bits and use the filtered oil for future frying. You can combine used oil with new oil to gradually use up what you already have. While there’s not a definite limit on how many times you can repurpose oil, it’s best to keep an eye on the appearance and scent of the oil—once it starts to deteriorate, it’s time to put it to rest (more on just how to do that below).
See What Your City Has to Offer
As far as discarding practices that are just as kind on the environment as they are on your pipes, you should start by seeing if your city has any processes set in place for addressing leftover oil. Start by calling your local environmental council, and they can advise you on best practices. Oftentimes, this is how fast food joints and restaurants dispose of their oil.
Take Matters into Your Own Hands
If that doesn’t work for you, you can also pour the (cooled) leftover oil into a non-recyclable container which you can then toss into the trash. If the idea of tossing a container of oil into the trash doesn’t sit right with your ecosystem morals, you can also create a designated area in your yard to dig a small hole and dispose of the oil there. If you compost, leftover oil can be added to the pile, as well. Just be careful not to overwhelm your composting bin or yard with too much oil, as this can attract vermin and other bacterias.