How do butter bells work?

Question

So I understand that the point of a butter bell is that your cup of butter is not exposed to the outside air because the water creates a seal. What I don’t understand is that there is still some air trapped between the butter and this water seal because the water doesn’t touch the butter. Is the reason why butter lasts longer because the amount of air and consequently bacteria the butter is exposed to less than if it was not in a seal? I would’ve thought that because the butter has the same surface area exposed to the air with or without the seal, the seal is unnecessary.

Please help, my girlfriend and I are fighting.

In: 24

Answer 1

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