Bubbles in Beer: Fascinating Phenomenon

Last night we had pizza and beer for supper (not an unuusual event in the Zut household). My wife uncapped her beer bottle (Franziskaner Hefeweissen), but unfortunately knocked it over at the same time. She was quick enough to right it before too much beer spilled, but of course the sharp rap made the bottle foam up and gush out. She cleaned up the countertop (took about three minutes) and sat down at the table.

“Hey, look at this” she says, and shows me the bottle. The bubbles in the head had aligned themselves in a nice regular hexagonal pattern against the bottle glass. Now, I know (or at least I think I do) why bubbles of the same size, which these were, would self-align in a nice hexagonal matrix. But, and here’s my question: why were all the bubbles the same size?

And, as corollaries: Are bubbles in beer always the same size? Why haven’t I noticed the hexagonal bubble pattern before? Or does it have something to do with this being a weiss beer (the sediment, I mean)? Or the sharp rap of tipping over the bottle?

bubble size has to do with rate of formation and hydrogen bonding in the liquid