We had friends round for dinner last night. There was a lot of cooking to do so as part of the prepping I made the dressing to go on a Thai prawn salad in the morning: lime juice, nam pla, chilllllllli, the usual suspects. By evening I could not taste the lime juice. Is that because I had been too long in the kitchen and had too many smells up my nose? Or do limes lose their flavour after squeezing?
It is likely that the salt in the nam pla neutralized the zing in the lime juice. Next time add the lime juice just before serving.
I like lime juice on boiled veggies. I've noticed that adding the juice in the kitchen while I am finishing other things does not taste as good as adding it at the table. I suspect it is the salt in the boiling water that dissipates the lime flavor (flavor).
I'm a limeaholic; I go through 2 or 3 every day.

I see where rolly's coming from, but I don't agree about the 'neutralisation' - more likely ye had a sweet beer.
A certain amount of the"zing" in citrus juice is caused by the acid, which can be neutralized by other ingredients or by heat, and by flavor compounds that can volatilize over time. It really is best added at the last minute--or at least only a few hours before serving a cold dressing.