There may be other reasons why the taste of soda would vary with the packaging. Despite enormous advances in can-lining technology, canned soda dissolves bits of metal through microscopic holes in the coating, affecting the flavor. read more
Smell. Taste and smell go hand in hand, and when you're drinking from a can, you can smell the soda better than when it's in a bottle. It's funny though--Beer's the opposite--Much better in glass. read more
Conversely, acetaldehyde in plastic bottles might migrate into the soda. The FDA regulates this kind of potential chemical contact, but even minute, allowable amounts could alter flavor. Your best bet for getting Coke's pure, unaltered taste is to drink it from a glass bottle, the most inert material it's served in. read more