On Wednesday, September 2, 2015 at 10:23:32 AM UTC-4, Janet B wrote:
>
> You guys do know that we are talking about a kitchen here and not a
> NASA lab? I reported my experience. The heavy cast iron lid is more
> successful in keeping moisture in the pot long term than stainless or
> glass lids. To make you all more comfortable, YMMV
> Janet US

That's the point, what really happens. For whatever reason the heavy cast iron lids do better at sealing. With mine I also add an aluminum foil layer. This acts as an excellent water vapor barrier. Any steam created that increases the pressure inside the pot will always escape. But this is small compared to vapor loss.

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