I don't know about Tupperware brand, but plastic storage containers have intriguing properties.
When you store pasta sauce or chili in plastic containers, they definitely retain some of the smell
and coloring; you can see the coloring after you've scrubbed out the discernible smell. I think they
hold in moisture, at least short term (months). But there is a decided exchange of materials between
the plastics and the contents. Beverages in plastic always taste a little different than the same
beverage in glass, and beverages in cans a little different again. Glass seems the most inert.