Belancan = stinky prawn paste.
I wanted to cook some laksa tonight and when I carved off a hunk of belancan I noticed it was out of date. It looked OK so I used it. There’s still a year’s worth of the stuff in the block.
It’s “off” already, so you can’t go by the smell. I don’t keep it in the fridge, just wrapped and in an air-tight container. It looks the same as when I bought it.
Is there a way to tell?
From my wife:
“if it’s not moldy, it’s still good”
“Belacan should be dry, if it’s not then it’s off”
“Belacan that’s gone really really off will have maggots crawling around it. Yes, maggots.”
So, if it’s not moldy, dry and no maggots…you’re good to go.
No maggots equals good. That’s my kind of food. Thanks.
Update, since I saw this skulking around in the pantry and remembered this thread: it’s still fine.
It’s quite dry but I roasted a little chunk in foil and whacked it with some dried anchovy, peanuts and chilli paste, then used it to top a hard boiled egg.
The same stuff, 12 years later? 
I’m working on a bottle of what I’ll call “thousand-year fish sauce.”
Sounds like the spices my mom left in the house, that pre-date the use of ZIP codes in the '60s.
2024 update: Just made a dish using the same unrefrigerated bottle of fish sauce. Still tastes fine.
When my dad died last year, my sister stuck around for a couple weeks, and one thing she did for my mother was clean out the pantry. She found an open can of breadcrumbs in the back, exp. 2008, and they still looked fresh! Egads! They probably weren’t really safe to eat in 2007, either, if you think about it.
Those went in the trash.
I have a small tin of white pepper I swear I bought the first time I ever bought groceries for my own house…don’t remember why.
I considered tossing it many times. But I click it open. Still smells peppery, mildly.
It’s like an old friend now.
Good. I also thought fish sauce wouldn’t spoil, but I had fungus growing in a bottle so threw it out. Maybe it was low quality fish sauce.
You would keep flalinig over.
This thread is a good reminder to clean out my pantry. There’s plenty in the back that my ex (and we’ve been divorced over ten years) bought, used once, and never touched subsequently. Neither have I. Fish sauce is one, and it’s just taking up space.
Eep! Now you’ve got me worried that any organisms in that back-of-the-pantry fish sauce have been there so long that they’ve developed their own political systems. Yep, out it will go.
Wouldn’t surprise me if someone tried to make a Casu Marzu style “delicacy” out of that,
Surely some suck-- er, I mean “Brave Soul,” would take the bait.
Where you’re eating maggot poop? Hey, anything’s possible.
I still have about a tablespoon of fish sauce left in a bottle I have probably had for 5-6 years. I’ve been using it steadily (obviously not very often, but a few times a year). It seems to have held up fine.
Years ago, I participated in a thread either here or on a related board about my ancient bottle of fish sauce. I can’t find it on either site with keywords crystal, crystalized, fish sauce, or nuoc mam, but perhaps some day it will bobble to the surface like something long dead.