>>>Well that's my preserve
>>
>>I never figured out why do(n't) they put preservatives in those jars.
>
>Because the content is preserved fruit. But sometimes there will be a preservative in - maybe the very process IS the preservative.
>
>In case you hadn't realised, "my preserve" here means like "my prerogative", "right" or "something reserved for me as a special person"
>
>So IOW "I'm allowed to make awful puns"

Mine was worse - in several languages other than English, a preservative is a condom.

Terry Pratchett calls them 'preventatives' in several places, probably referring to this usage of the word.