How to Clean Dirty Cooking Oil

True confessions time:  Like many young women, I did not learn to cook much from my mother.  I did learn a little about baking cookies and making spaghetti sauce, but that was about it for direct instruction.  I could follow a recipe with reasonable success and wasn’t afraid of being in the kitchen, but beyond that I was fairly ignorant. 

During the first few years of our marriage, meals were pretty simple.  That’s generally how it is when you have little children and dinners have to be ready at 5:30 each day.  (That’s the way it is with my diabetic husband—blood sugars are much easier to manage with a set meal schedule, and especially with dinner occurring a few hours before bedtime.)  I rarely deep-fried anything.  That took too much time, but more significantly, there was a lot of oil involved.  Oil that obviously got contaminated and had to be thrown away.

I didn’t know that oil could be saved.

After a while, I decided that I could try to save the oil if I ran it through a sieve to filter out the bits of crud.  I wasn’t sure this was kosher, but after the reclaimed oil worked in making bread, I decided I didn’t care.  Of course, now I know that this is standard practice, so it’s no big deal. 

For over a decade, when I was baking three loaves of bread every week for family, we rotated through the used oil really well.  The oil was only used for deep frying once or twice before it was turned into bread.  It rarely got very dark and dirty.

But now, with only one child at home, I make bread about every three weeks.  However, my sons and their families come for dinner on the weekends.  I have more time for meal prep, and we do a bit more deep frying.  And sometimes the oil gets really gross—dirty and dark.  I still use it in making bread, but I am always worried that I’m going to be caught someday.  Yes, that dirty, used cooking oil being reused in the bread baking has been a dirty little secret for a long time.

So when I stumbled upon a method for cleaning used cooking oil, I was really intrigued.  Because I know there are people out there for whom this is an issue.  It certainly would be for my husband if he knew about it. And all you need is a packet (well, just a teaspoon) of unflavored gelatin.  If you are interested in the science behind why this works, take a look at the reference below.

Very important!  Make sure the oil you are cleaning is at room temperature.

For every quart of oil to be cleaned:

• In a small saucepan, measure ½ cup of cool water.  Sprinkle 1 teaspoon of unflavored gelatin over the water and let sit for a few minutes. 
• Bring the gelatin-water to a simmer over medium heat, stirring constantly until dissolved. 
• Pour the gelatin mixture into the dirty oil, stirring constantly and vigorously, to the point where the oil looks very cloudy and the whole mixture is rather homogenous.  As the oil now needs to be refrigerated, you can transfer it to a glass jar or you can keep it in the pot and cover it.
• Let sit overnight.
• The next morning, pour off the oil into a clean jar.  Discard the gelatin that remains in the bottom of the jar.  The cleaned oil is now ready to use.
• This oil will likely still contain some droplets of water.  These will eventually be released as the pan and oil heat up.

Real world review:  The oil is definitely much cleaner than it was when I started, but not as clean as I thought it would get.  The gelatin didn’t coalesce into a little disk that I could pick up and discard, but I also started with about ½ cup more oil than I should have for this recipe.  However, the gelatin and all the gunkies in the oil were at the bottom of the jar.  So I would do this again if I felt the need to make my oil look cleaner. 

References:

https://www.seriouseats.com/clean-cooking-oil-with-gelatin-technique#howto

at February 25, 2022

 2.25.22