Human body has remarkable ability to metabolize a vast array of chemicals gaining entry through food and medicines because of the activity of the omnipotent organ, Liver which has a plethora of enzymes to deal with many toxins and unwanted substances. But there are some foods with strong aroma, when consumed, can contribute to smell in the breath, sweat, urine and feces because of the passage of the constituents through digestive system, blood stream and kidneys, practically unaltered to be excreted from the body. As these aromatic substances are volatile in nature, those who consume become literally an "odorant" contaminating the environment around for some time. Consuming such foods in summer can enhance the dissemination of the aroma while in winter the effect will last longer.
It is rightly said that 'one man's food is another one's poison' and this is literally true in the case of several 'smelly' or 'stinking foods' like Durian, Jack fruit and Garlic. Those who like these foods are emotionally attached to them. swearing by the 'delicacy' of their flavor while those detesting them cannot stand these foods which evoke strong adverse reactions including nausea. vomiting and diarrhea. The strong aroma emanating from such strong-smelling products is mostly due to sulfur compounds present in them which are volatile in nature, though non-sulfur containing chemicals also contribute in some cases. Though advanced analytical techniques and sophisticated instruments are now available to unravel the chemical nature of these aromatic substances, not much is known about how they are metabolized by the body once ingested through the food.
Durian is often termed as King of Fruits in South East Asian Countries like Malaysia, Thailand and Indonesia (just like mango in India) and the population there love these fruits in spite of the strong smell associated with the ripe fruit. Durian is a fruit, 'non grata' for those out side this region because of its very strong aroma which does not leave the body for some time once consumed. Sulfur containing compounds like 3,5 dimethyl-1,2,4-trithiotane and 5-ethyl thioacetate and non-sulfur compound ethyl-2-methylbutanoate contribute significantly to the smell characteristic of Durian. Probably these substances are not metabolized in the body to make them odorless and find their way into excretory system unchanged. Nutritionally 243 gm of edible part of Durian provides 360 kC of energy, 66 gm of carbohydrates, 3.6 gm of protein, 9.2 gm of dietary fiber and 13 gm of fat, and a score of vitamins and minerals making it an impressively nutritious fruit.
Jack fruit, more popular in India and other south Asian countries, is another strongly smelling fruit liked and hated by people with different eating habits. It is a common sight in these countries to see street vendors offering peeled and cleaned fruit bulbs after deseeding during the season, May to August. Unlike Durian, this fruit does not have very heavy notes in its aromatic chemical make up but still it is a strong smelling food. Isopentyl isovalerate, butyl isovalerate, butyl acetate, ethyl isovalerate and 2-methylbutylactetate, all non-sulfur containing chemicals make up the aroma of jack fruit. As these are simple chemicals, they get easy entry into the blood, are circulated and excreted more or less unchanged giving the excretory and secretory substances from the body the typical aroma of Jack fruit. Unlike Durian eating, normal quantities of jack fruit generally do not cause any body odor and being heavy to the stomach because of its texture and composition, the serving size is invariably self-limited. More ripe the fruit, higher will be the intensity of the aroma and peeling such fruits can disseminate the smell into the environment more rapidly. Products like preserves, jams, syrups, fruit bar and others made from jack fruit through thermal processing, have more intense odor and consumption of these processed products can cause very strong pollution of the environment.
Garlic, considered more a condiment, is a strong smelling food adjunct possessing a wide array of beneficial properties for human beings. Diallyl sulfide, Alliin, Ajoene and s-Allyl cysteine are considered responsible for the strong aromatic note associated with it. Allicin, the most famous active principle for which garlic is well known, is responsible for the 'hot' sensation experienced on its consumption. Allixin, a non-sulfur containing substance, present in garlic, confers on it the unique health promoting properties as an antioxidant, microbicide, anti-tumor agent, anti-aflatoxin binder to DNA and neurotrophic substance. The sulfur compounds in garlic when consumed get converted to Allyl Methyl Sulfide (AMS), the typical smell associated with sweating and breathing of those consuming garlic.
No wonder these smelly products, besides being liked for their typical aroma, are also nutritious foods in their own right. Unfortunately, human beings diverse in their food preferences differ in their perception of foods and there is a substantial population who shun such smelly foods to avoid polluting the environment with such odors through their body secretions and do not become a social nuisance to others. Immigrant populations in western countries who are used to these foods, consciously abstain from eating them regularly, confining consumption during week ends, appreciating the potential for discomfort to their fellow workers during week days. In the case of garlic there are odorless preparations available in the market in the form of encapsulated products which can be swallowed without experiencing the smell in the olfactory system. With the reach of biotechnology sparing no area of human endeavor, is there a possibility that new versions of these foods may appear devoid of the odor but preserving all the goodness for which they are known, through intervention of biotechnology? Very little chance indeed!