I think I found it. I must have gone out and bought some after the sample worked so well. The tube doesn't look familiar, but could easily be different from the way the sample tube looked. It's meant as a dishwasher additive to be used in conjunction with regular dishwashing detergent.

The active ingredient listed is Benzoyl Peroxide. I know from unfortunate experience that Benzoyl Peroxide takes color out of lots of things.

"Cascade Plastic booster.

Plastic cleaning additive.

Use regularly to:

- Removes red stains and odors"

Though turmeric isn't red, I would think this would work on other stains as well. I don't remember if I tried using it NOT in the dishwasher as well as in.