On Wed, 06 Apr 2011 22:01:28 -0700, HumBug! >
wrote:

snip

>
>Mustard DOES NOT expire, and I've never seen an expiration date on mine.
>
>I shake my bottle every time I use it, as it does separate,
>NOT AN Fing problem!
>

Mustard may not go "bad." but it does lose pungency and it turns dark.
Old mustard has very little flavor beyond salt and vinegar.
Janet