We just got back from WDW. On our trip down, our supper included a small cup (like one of those juice cups that have a plastic cup and the top is sealed with foil). When I opened mine, I was surprised how the foil was bullged out from the pressure and a little water spurted out when I peeled the foil. After seeing that, I would be afaid to carry any pop in my luggage. It probably would be OK, but, what a mess if it does explode.