As an experiment, (that’s what I call it now – but I was just perpetually lazy), I left a bag of grain that was already crushed
from the shop, hops, and a packet of 05 in the bottom of the garage fridge for just under 2 YEARS! The grain lost like 30% of it’s weight – which totally shocked me; presumably moisture – and I was fully expecting to have zero start with dead yeast but that sucker took off within hours and turned out very good; about on par for what I was doing before fermentation temp control and huge starters.
I did a similar “experiment”, for 18months: but the Wyeast was completely dead.
(This hints sharply to why "I've been brewing for over 20 years" but still suck!
However, for posterity, I have ZERO pause for ingredients going wonky over time – except for liquid yeast!