I have a bulk dispenser I use for gatherings. Took it apart yesterday to clean. There are some custom silicone fittings that are very coffee stained. What is the best way to deep clean them without damaging the integrity of the silicone?

First thing I'd try, based on the "first do no harm" maxim, is baking soda and a small bottle brush. Make a thin paste. It probably won't get all of the stain off, but it will remove a lot of it.

Best,
David

I would soak in TSP/espresso machine cleaner then rinse in reasonably hot water. I would not use a brush because if it is getting stained now, you do not want to scuff up the surface giving the coffee more places to "hide."

farmroast wrote:I have a bulk dispenser I use for gatherings. Took it apart yesterday to clean. There are some custom silicone fittings that are very coffee stained. What is the best way to deep clean them without damaging the integrity of the silicone?

I doubt that's possible. Many polymers happily dissolve a variety of oils, along with whatever oil-soluble pigments they carry. I see it with gaskets on airpots, and on white polyethylene cutting boards when they come in contact with things like avocado, BBQ (pork fat, red pepper) basil pesto (olive oil) and dried tomatoes (olive oil). Bleach lightens it a bit on the surface, but not much. Exposure to air and light does a better job, but it takes days to weeks. UV (sunlight) might accelerate that, and might also accelerate aging of the polymer.

Give it a short soak in JoeGlo and rinse it off.