Mustard is only good for 2 months in the fridge. Hmmmm, is it the vinegar or the tumeric that goes bad?
I’m sorry, 6 to 8 months for mustard (still a short time in my opinion), ketchup is 1 month unrefrigerated, longer in the fridge (I’ve had mine for quite a while, tastes fine).
It depends a lot on the temperature inside the refrigerator.
I’ve had mustard that lasted longer than 2 months but I just pitched a jar I had in the fridge at the office for 4 months because it had turned.