Barbara,
well, if you don't eat an excess of fruit, combine correctly, drink outside
meals, and still have noises when drinking a glass of water alone, then I give
up (I can't find any explanation)!!
I don't think we should be excessively concerned about noises (provided they
don't exceed a reasonable limit). I know people (on cooked food) who have such
noises too, and babies also burp after drinking milk.