This is pretty interesting. For those familiar with winemaking, there is a technique called carbonic maceration where grapes will self-ferment intracellularly i

This is pretty interesting. For those familiar with winemaking, there is a technique called carbonic maceration where grapes will self-ferment intracellularly in an anaerobic environment. Typically even if you don't artificially create an anaerobic environment (by pumping in CO2), if you put enough grapes in a sealed chamber the ones on the bottom will get crushed by the weight of the grapes above and the yeast living on the skins will kickstart carbonic maceration for the rest of the grapes (by producing CO2). That may be one reason why the containers they make to store the grapes are relatively shallow; a larger vessel such as a pot may inadvertently crush some grapes and lead to making wine instead of storing your grapes!