We've bought a house and found half a large tub of bokashi bran in the basement. This puzzled us a while as we'd never heard of the process, but a little Googling enlightened us. We've also got some bins, also left by the previous owners so we're interested in giving it a go.
We've no idea how old the kit is. Given the state of the bins (found under an archaeological layer of rubbish) and the wormery (well past it and the wooden lid rotted) I'd say it's probably been some years since any composting method was tried here.
Does the bran expire? It's been kept in cool dry conditions in a reasonable tub with a lid (loosely) on.