Agreed ^_^
In real world there's breast-feeding, a beautiful process in which milk will have banana flavour if you treat your lady with banana split/sundae shortly before it. Basically whatever is in the food will be in the milk
Similarly, in a fantasy entire body becomes a balloon, including every dessert she has been enjoying before it. Sure, massive fantasy amounts of air/helium leave body only during deflation - but hey, some creeping leaking is always there, through skin and nostrils if nothing else. It's not enough to deflate her visibly but quite enough to soak surrounding in rich flavours of her perfume and, well, foods and beverages consumed recently. Those ignorant of it might choose barbecue and beans (in which case I wouldn't want to be around), those mindful of it might have, say, a cup of milk and toasts with honey before inflation
Just a weird thought ^_^
"That just raises further questions!" - Hermes
But seriously, some more context to this banana/inflation hypothesis would be nice. Are you talking about an alternative to blueberry inflation where the person takes on the colour and qualities of the fruit/flavour they ingested, or just normal air/water inflation on a person who just happened to eat a banana? Because the first scenario would be a likely 'yes', the second one a 'probably not'.