I'm pretty sure that Jone recommends something like 15 minutes after having received communion, for not eating anything afterwards. AFAIK canon law doesn't address it. Common sense would tell you that to eat something 5 minutes after having received, would risk being sacrilege --- think of laying a candy bar or a gulp of coffee over the Body of Christ, and it will make sense.
I tend to have a dry mouth and throat (probably due to medications), so I generally carry a bottle of water with me in the car, and take a drink of it as soon as I have left the church, which would be about 15-20 minutes after receiving, at the very least (should be more). This way I avoid having the Sacred Species to be clinging to my throat.
Our Lord willed that we would eat His Body, so how something like this is handled, should never be a scruple.