The smell of rotten eggs comes from sulphur containing foods, dairy products,eggs,red meat,milk,cabbage,broccoli,mustards ,onion, sweet potatoes, vitamin B1,biotin,legumes,peas,beans ,
walnuts, almonds are all sulphur containing
foods. The common causes of such smell are a gastro-intestinal infection caused by the Helicobacter pylori bacteria or Giardia.Parasitic infestations like giardia lamblia, fructose intolerance can also cause sulphur burps.