If I remember correctly, fats are very similar to plastics in molecular structure. The oils in pasta sauces get stained red, and in turn the oils like to hang on to the plastic, making them stained. It gets tricky to thoroughly wash all of the oils off the plastic because they want to stick together. One of the tricks I’ve heard to prevent staining is to spray plastic containers with regular non-stick pan spray before adding the pasta, so the clear non-stick spray oils sticks to the plastic before the stained pasta oils do.
This is also why you can wash a plastic container and sometimes it still feels a little oily or takes finger prints easily.
AugustWest@lemmy.world 1 day ago
This might change someone’s life: Instead of washing your spaghetti stained plastic container with a sponge or throwing it in the dishwasher, fill the container to maybe 30% full with hot tap water, add a couple pumps of dish soap, chuck in a paper towel, close the top, and shake. It’s honestly astonishing how effective that is.
SCmSTR@lemmy.blahaj.zone 1 day ago
What role does the paper towel perform?
AugustWest@lemmy.world 1 day ago
Basically what’s been said. Lycopene is the pigment that is staining. It’s hydrophobic and is really good at bonding to plastics for reasons outside my understanding. Soap and abrasion will loosen it, but because it’s hydrophobic it has nowhere to go. The absorbent paper towel gives it something else to bond to.
jaybone@lemmy.zip 1 day ago
@remindme@mstdn.social 1 day
GoodStuffEh@lemmy.ca 1 day ago
My entirely unqualified thought is that it gives the food particles something to bind to that isn’t the plastic of the container
SCmSTR@lemmy.blahaj.zone 1 day ago
My thoughts, too. That, and maybe some slight abrasion?
Watch it be something ridiculous like “the slight fibers are exfoliated from the paper by the soap, and those exponentially increase surface area of the degreaser in the soap and combine with the minute amount of bleach in the white paper towel to form a new chemical agent that’s highly effective in bleaching and degreasing that specific type of plastic and polarized fat, separating the two in a volumetric capillary action that essentially transfers the stain onto the fibers of the paper.”