I recently brewed up an IPA recipe and used Alexander Pale Malt (9lbs) that was 2-3 years old. It had never been opened so any oxidation was limited to just sitting in the plastic tub in a closet. Anyway, it was much darker than the 3lbs of Alexanders' I added to complete the recipe - dark like molasses. It tasted fine and had a chocolatey finish. There was no evidence of any mold. It's consistency was the same as the new malt, just much darker.
Cut to the chase, the IPA was also dark, like Coca-Cola, throughout the process (wort, bucket, carboy, keg, glass). The taste after a week in the carboy was soy saucy and a hint of coffee. Needless to say, I was bummed that I had just brewed 5G's of bad beer. Well, beer with a weird finish. I tried to rationalize that I was tasting warm, flat beer - the worst adjectives you could attribute to your favorite libation. Out of the carboy, it tasted the same - prolonging my regret. It sat in the carboy for 2 weeks and then I kegged it. I couldn't help but sample it a few days in the kegerator, so could decide to dump or keep it. I kept tasting it for a few days, and much to my delight it was tasting better and better. I thought I was just imagining the improvement. I brought a sample to the homebrew store and the guy there described it as a good English brown ale. I reminded him that it was an IPA, and he replied, "Where'd the hops go?" Mind you this recipe called for about 6 additions of hops. Nonetheless, I have a good beer after all. Would I recommend using old malt? No. The lesson here is that it's hard to keep a good beer down. If you brewed well, things will work out. Also, give the beer a chance to do its thing. The week in the keg was a must. It allowed it to carbonate and temper/develop it flavors.
