Bill, Thank you once again for your contributions to BA! You bring up an excellent point re: Kolsch: “It was a shadow of the beer it was when fresh, but in a very different way than a hop-bomb IPA would be. The malt flavor was still intact and everything was technically still in spec, but the balance was off and the beer tasted...muddled, I guess.” It is popular on BA to discuss a beer going stale by stating that cardboard (or other flavors like sherry, etc.,) develop. In a recent issue of Zymurgy Gordon Strong discussed old beer/staling/oxidation: “Old beer is simply stale and dull with muted flavors. … Flavor intensity decays and the balance might change as different components degrade at varying rates.” “Many breweries misidentify oxidation because they are expecting wet cardboard, sherry or paper flavors. That’s a specific kind of oxidation but not the most common. Oxidized beers generally have a dullness of flavor…” Cheers!