Hi - just to let you know I have done LOADSA reserch on this thing - thought I'd share what I've tried on my bro (who had bad breath!) and has now cured! If you've got acid reflux might be because you have too low stomach acid, instead of too high (I know that sounds really weird!) but to test it, try this...when you have symptoms take a tablespoon or so of lemon juice (I gave him concentrated) and if the hiccuping/heartburn goes you know its because you have to low! This DOES cause bad breath and is easy to get rid of by simply just adding stomach acid before you eat, with HCL tablets (easily available!) ....also, digestive stuff can cause bad breath, his bad breath was directly linked to constipation (which ironically showed itself through diarreah, extreme constipation!)...he changed to a really high fibre diet and within 2 weeks bad breath gone, sweet breath HELLO!
Simple as that! Try the lemon juice thing....and think about whether you have constipation or not...(if its low stomach acid, is simply that you don't have enough to break down food, therefore is putrefying, i.e. smelling!)