Yes, it's a physics related question. Read on.
I know from general knowledge that in order to produce a decent wine, you must keep it in a dark place. Therefore, from my knowledge of physics I guess that the process of wine making doesn't need much energy (I mean the reactions etc). Also I presume it gets the energy from visible light, IR, UV light and all the electromagnetic spectrum. However, you can see most of the wine bottles are painted in dark colors, which brings me to think that they attract more energy from electromagnetic waves than they would if they were painted in brighter colors. However, in those cellars they're kept in, hardly any light goes inside, but still wouldn't it be more efficient to paint them in solid (so you can't see through) colors (white spray, duh)?