As far as I know uncrushed grain should store for a long, long time as long as you keep insects away from it. 12 months, at least, assuming it's kept dry and cool etc.
I had to chuck half a sack of Marris Otter that was full of some kind of miscellaneous bugs over the weekend. Just about shed a tear.
Ok thanks, good to know coz I've got 40kg of 2 row coming... I was planning on dividing into 5kg bags and vac sealing anyway.
I feel for you having to throw that marris otter out too, definitely tear worthy.
I keep my grain in plastic water containers from Bunnings, with the sealed lids. Roughly 2 litres of space for every kilo of grain, one 25kg sack fills up a whole 25 litre drum and then about 80% of a second one. Nothing can get in or out, totally sealed, and probably a lot more convenient than vacuum sealing it (you can just pour out how much you need).
Yeah, vac packing your grain might make you go bonkers
I keep all mine in various types of sealed tubs, these are mainly splits from a bulk buy. I've also got some base malt in sacks in a plastic dustbin type thing. I've had some for over 18 months, still tastes good.
3-litre orange juice containers will hold 2.00kg of specialty grains but a less if storing flaked products.
Bulk grain is stored in various containers still in the (tightly sealed) sack.
If you're short on space (as I am) square is better than round.