Yes, I know exactly what you are thinking: what the hell is a “desert truffle”? Is it a euphemism for camel dung or some weird sand dune configuration?
No, desert truffles are very real. Just like the more familiar European truffles, desert truffles are fungi with underground fruiting bodies that grow in a symbiotic relationship with the roots of specific plants. Desert truffle species have been found in Africa, the Middle East, south Asia, and even in China, and as the name suggests, they are usually found in areas with dry climates. They are a bit more common than European truffles (and often larger too).
|This photo appears on several websites but I was not able to identify the original source. This gives you a great idea of the size of these things.|
A very old myth common across North Africa and the Middle East says these fungi grow only where lightning has struck the ground or, in an alternate version, that it is the rumble of thunder brings the fungi close to the surface. That’s of course silly but in order to grow, the desert truffles need some well-timed early winter rain. Storms in the desert can be accompanied by thunder and lightning, so the association is sort of reasonable, just not directly causal. (You can find some amazing pseudo-scientific babble about lightning, nitrates, and truffles here. It’s total nonsense. Don’t believe everything you read on the Internet. And it's very disappointing that a botany department at a very good school would link to such pseudo-science.)
Desert truffles are sometimes used for medicinal purposes but mostly they are eaten (fungi are decent sources of protein). A traditional method is to roast them like potatoes in a fire (they are often described as resembling sandy potatoes and are thus treated like potatoes when cooking with them) or fry them in oil. I found several recipes for making truffle soup using camel milk.
|Another photo with no clear source. Fungi masquerading as "sandy potatoes".|
It appears there is a tempest in a teacup amongst the scientifically illiterate over “true” and “false” truffles. (This site states that the difference between “true” and “false” truffles is based on their "gastronomic" uses [he meant "culinary"]. Utter nonsense. However, the site does have a very good set of photos of the main desert truffle species. It's worth a visit for the photos but you can skip the introductory text.)
A quick scan of a few peer-reviewed scientific articles cleared up the matter of “true” versus “false” truffles (for example, see this paper and this one too). Nearly all fungal groups contain species which develop lumpy, underground fruiting bodies. The principal difference between “true” and “false” truffles is the way they produce spores (“true” truffles have round or elliptical spores while "false" truffles have club-shaped spores). The group Ascomyota contains the “true” desert truffle species. The main genus of European truffles is Tuber (yes, that's the same word we use for potato in English but truffles and potatoes aren’t related) and the main genera of desert truffles are Terfezia and Tirmania. Saudis call desert truffles "fa'qa" (many spelling variations exist), but they are widely called "terfez" across other parts of the Middle East (which is of course where the genus name came from).
We are now entering truffle season here in Saudi Arabia. Some of the Saudis with family farms have been talking about going truffle collecting (the sites are revisited year after year and their locations, just as in Europe, are generally kept secret). Since I'm not already a fan of truffles, I probably won't make an effort to find the desert variety in a local market. Even so, it was interesting to learn about these weird desert fungi.