The original barrel is an amphora. Barrels do two things when storing spirits, they add water and alcohol soluble wood components, and the provide oxidation reactions. Ceramic vessels can be made where they are essentially glass, like a porcelain tea cup, or they can be made where they leak water like with a flower pot. There are a few traditions such as awamori and pisco that use ceramic vessels for maturation. Does anyone have any information on how ceramic vessels are made for aging (types of clay, temperature fired) that can balance being porous enough to age, but not too much to loose spirit? And what the effects of maturation in a ceramic vessel are?
Interesting thought. Could be neat way to age something like a white rum that you just want to mellow without adding any barrel flavor or an age statement to.
When I was making beer, I remember seeing concrete fermenters at a trade show. They look like a mix of a giant egg, and an ancient statue of a fertility god. Think they are usually used for wine, but they were pitching them for wild/sour beers. Some Yeast/air/bacteria stays in the pores kind of like a foudre. Hadn't thought about it till now, but they might be ideal for spirit fermentation. I think they were quite expensive though.