The Baking Staple That Helps Get Rid Of Used Cooking Oil
Any time you make eggs or saute vegetables, you don't have to worry about discarding the leftover cooking oil because there's hardly any remaining by the time you're finished cooking. But if you decide to deep fry something, you're bound to have extra left over. Luckily, this oil can be saved and reused, but after heating it a few times, it starts to harbor too much debris and odor while the smoke point gets lower and lower, rendering it ineffective for frying. At this point, it's best to discard it.
When it comes to discarding used cooking oil, hopefully, most people know you shouldn't pour it down the drain as it can clog your pipes. The most common way to get rid of it is to wait until the oil cools and solidifies, then toss it in the trash, but a much more convenient approach is to use baking soda. Simply add some to your greasy pan, stir it around until the two are combined, and scrape the resulting clump into the trash.
Why baking soda is ideal for discarding oil
Though you might assume that any powdery substance such as flour or cornstarch would produce the same outcome, baking soda does more than just absorb the oil to make it easier to discard. Baking soda is an alkali, and when alkalis and oil come in contact with each other, two things happen: the alkali soaks up the oil, and the oil dissolves (per Engine Builder). What this means is that when you add baking soda to oil, it not only clumps up, it also breaks down the oil in the process. As a result, your pan will be a breeze to clean up too.
When using baking soda to discard oil, you'll actually want to be pretty generous with it. Measuring isn't necessary, but you should pour over enough baking soda to cover most of the oil. If you use too little, it'll still be greasy and not much will happen.
What do do if you don't have baking soda
If you don't have any baking soda on hand but still need an alternative to pouring your hot oil down the drain, baking powder can work just as well. While the two have slightly different functions in baking, they both have a similar effect on used cooking oil. Baking powder is made up of acid salt, starch, and most importantly, powdered alkaline, which is what causes oil to dissolve.
When you have neither baking powder nor baking soda on hand, don't resort to another baking staple like flour; it simply won't do anything other than create a paste out of the oil. Instead, line a bowl with aluminum foil, and pour the hot oil into it. You'll have to wait until the oil cools, but then you can toss it out. Unfortunately, without the baking soda to alkalize the oil, you'll still have to scrub your pan pretty thoroughly as well.