It is nicknamed the "King of Fruits," however, the unique aroma of the durian fruit, native to Southeast Asia, has left many describing it more like rotting onions, rotten eggs or even a gas leak.
The scent of durian is so foul that it is banned from being brought on board or consumed on the Singapore rail system. This distinguishing feature of the exotic fruit made a group of scientists decide to look more closely at what it is composed of to figure out what exactly gives it its trademark stench. The research team published their findings with the National Center for Biotechnology Information (NCBI).
What the researchers found was a treasure trove of stinky chemicals. And although each of these chemicals may not be tremendously malodorous on their own, as a collective, they all contribute to the nauseating smell that has offended many noses.
Thai durians were used in the research and 44 chemicals were identified via solvent extraction where samples from the fruit are put into vials of different liquids and put in a centrifugal spinner to isolate the chemicals from each other.
In 2012, researchers from the German Research Center for Food Chemistry did an analysis of the durian fruit using mass spectrometer and gas chromatograph techniques to identify the stench-inducing chemicals.
Both studies list a few chemicals that are known to be smelly on their own, like hydrogen sulfide and methanethiol. But they also found some other chemicals which are actually associated with pleasant aromas such as the honey-scented ethyl cinnamate, the caramelly 4-hydroxy-2,5-dimethylfuran-3(2H)-one and the fruity acetaldehyde.
In the onion-scented chemicals category, however, are the following culprits: 1-(ethylsulfanyl)ethanethiol which gives off a roasted onion smell, the sulfury onion-smelling 1-(ethyldisulfanyl)-1-(ethylsulfanyl)ethane and ethanethiol, which smells like rotten onions.
The full list of chemicals found in a Thai Durian fruit can be read in the abstract of the published study on the NCBI website.