Thanks, I was pretty sure the worst thing that could happen is aroma not being as intense, as it was originally. I was just anxious if there is something I had no clue about, since all I could find about malt storage was "more than one year is no-go".

Two years ago I bought 1kg of Weyermann Special W malt, completely forgot about it and found just now. It was stored in a plain plastic ziploc, below room temperature and relatively dry. The malt smells and tastes just fine. Is it usable? If yes, how much longer can I store it?