There are many different Durio cultivars, but the one that is most commercially produced is the Durio zibethinus. It is a curious, fruit when you first see it as it looks a little like a small jackfruit, but that is where the resemblance ends; they are not related. The fruit inside its thorny case is unusual to say the least. The husk has to be split open by the fruit seller on roadsides in Thailand, with a machete, or something that looks very like one, and inside there are slimy looking banana-type fruits, which contain large seeds. People complain about the smell and the fruit has been banned in some hotels and on public transport in parts of south east Asia, but I don’t remember the smell, perhaps because we bought the fruit in the open air and the atmosphere was quite polluted, so one more smell was not noticeable.
It is believed that the seeds contain toxins which can cause shortness of breath, so they should not be eaten raw. People with high blood pressure and pregnant women should avoid eating durian.
If you buy durian paste in markets in Thailand, it might have been adulterated with pumpkin, which is cheaper. However this may make it more palatable to some.
Don’t worry if you’ve never tried it, personally I think it’s another over-hyped fruit like the mangosteen.