bacterial i guess, same way just putting it on the shelf would normally cause it to rot, but in this instance the energy released by the rotting fruit is directed toward an entity
the longer it lasts, the more powerful the fruit was
when they replace the fruit (about every 2 weeks, or when it starts to stink) they light the incense and say a little mantra-like chant (i suppose to link the fruit to the entity)
the food stuffs placed outside the ancient egyptian tombs, along with a symbol of the action desired (as in protection, wealth, etc) is so similar it makes me think of it being based on the same thing
e.
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