The contents of flatulence
According to a nutritionist named Chen Tao, flatulence consists of 70% air taken in while talking and eating and drinking, and 30% of waste from digestion, decomposition of food by intestinal bacteria and yeast, catabolism and catabolic metabolism.
Gaseous flatulence consists of 59% nitrogen, 3% oxygen, 21% hydrogen, 9% carbon dioxide, 7% methane, 1% odoriferous substances such as hydrogen sulfide and indole.
With a 7% methane exhaust, no wonder flatulence smells foul!
Foods such as meat, fish, eggs, dairy foods, beans are decomposed by deamination, decarboxylation, desulfuration, to produce hydrogen sulfide that gives out the rotten egg smell. Other foods that have particular characteristic smells include the strong Indian spices, onion, garlic, carrots and Chinese chives.