we have a jar of 'woh hup' *black bean paste* (mild).

Here in London u.k., we invariably have information on the jar's label about
when the contents must be *consumed by*, once opened. That's as well as the
usual *best before* date stamped on the lid, (that's for before its opened).

This bean paste is imported from Singapore and does not have any 'consume
by' information on the label. It only says refrigerate after opening. The
contents are listed as: black beans, vegetable oil, salt, chili, yeast
extract, and sugar, sesame oil, and natural spices.

My son takes this to mean there is no 'consume by' date applicable and it's
still in the fridge for many months 'after' being opened. Do you think
this is safe to use? I know some things last forever, i.e. fermented Soya
bean paste (miso) and pickled salt plums and the proprietor of our local
Indian shops says his jars of pickles would last forever and is annoyed food
regulations force him to put a 'best before' date on his pickles.

Maybe the 'original market' Chinese would automatically know if it should be
used more or less straight-away, but here in London we don't have a clue,
and feel uneasy with my son's optimism about this paste. Grateful for
advice on how long we can safely keep it please.