Hi Bob, I was partly joking, and have oft heard various things suggested as being bad for your vocal cords, from milk, to fruit juice to whisky. Of course if you do accidentally inhale liquid, i.e. choke, it will be very uncomfortable, so perhaps water is safest and least irritant!
As for any other things if you have to sing with a rough throat, lots of folk seem to swear by Vocalzones, but then I've seen others use mixes of port and brandy! No, stick to water, I think