Today on 720 ABC Jane Marwick asked Dr Karl how to get cooking oil stains out of a cotton shirt. Although Dr Karl is a very knowledgeable man, he is a physicist and biologist, and this is a question for a chemist (like me).
Fortunately, this is a very easy question to answer. There are many ways to get cooking oil out of a cotton shirt, depending on what you will have lying around, and any of the following will work:
1. Oven cleaner. Oven cleaners are excellent general purpose hard surface cleaners and degreasers. The reason for this should be obvious – cleaning an oven of course requires removing grease and oil, and if the stain in your shirt is either grease or oil the oven cleaner will work nicely. The chemical process is called saponification. That is, the oven cleaner converts the triglycerides to soap, which is exactly how our great grandmothers used to make soap at home – caustic soda (lye) mixed with cooking oil. So squirt some oven cleaner onto the stain and work it in with your fingers. Wait a few minutes and pop it in the wash. Or, just rinse it out with water, let it dry and bobs your uncle .
2. Degreaser. Any hardware store these days stocks a range of degreasers. There are two basic types, the solvent based formulas which are the older type, and the alkaline salt based degreasers which are the more modern type. Get one of the latter (to make sure you have the right stuff look for the phrase “alkaline salts” somewhere on the label). Use it as a pre-wash – squirt some onto the stain, pop it in the wash, and it will come out clean as a whistle .
3. Enzyme based cleaners. White King make an excellent enzyme based laundry prewash (stainlift) which will do the job. Squirt some on, work it in with your fingers, then pop it in the wash . Alternatively, get some Biozet Attack and use it the same way. The beauty of working it in with your fingers is that enzymes perform best at about body temperature, since they are naturally occurring molecules. And therefore washing in warm water, as opposed to hot or cold, increases the performance of the enzymes.
4. Acetone will also get the oil out (available from any hardware store ). But test an inconspicuous part of the garment first, as acetone will also dissolve some garment dyes.
5. Washing soda. Make it into a paste, rub it into the stain then rinse. Repeat if necessary.
5. Dishwashing liquid. If you aren’t already using it, get some Morning Fresh which is the most concentrated dishwashing detergent on the market, and use it as a spot cleaner. It won’t be as efficient as the methods above,, but if you’re too lazy to go to the shops it will work. Rub it in with your fingers, rinse, repeat and rinse until the stain is gone.
So you see Jane it’s pretty easy – you just have to ask the right person.