Some breweries are constantly making changes in their recipes and even if they don't, the ingredients change a bit. It's easier for the big companies to be consistent because they can afford to test each shipment. Widmer uses a finely tuned mix of hops in most of their ales, which is one reason they are hard to duplicate at home.
Storage conditions matter, shipping conditions, length of storage.
Then there's the bottle vs. keg factor. I'd expect coffee to be much more pronounced in a fresh keg.
The Swanson Effect in the food industry is the art of slightly changing your recipe so people don't get bored. They think they are eating the same item, but it isn't exactly the same on purpose.
Eventually, you get to the point where you can identify what changes were made in a batch.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
"I would like to die on Mars, just not on impact." Elon Musk
Last edited by david_42; 01-28-2008 at 01:40 AM.