No, it's not a chocolate truffle. Mattirolomyces terfezioides (=Terfezia terfezioides) is a very sweet hypogeous fungus (fungi that ripen completely underground), as sweet as saccharin. Hungary is the only country where they occur frequently, in Robinia pseudoacacia forest. Fruiting period lasts from August to November. Popular name is “homoki szarvasgomba”. Because of its sweetness, unique and very personal, it is mainly used to make desserts, like sorbets, ice creams and cakes.
On the rare occasions when they have been found in Spain, they were in gardens, under fruit trees, such as the big one, more than 20 cm long, that was found under an orange tree (F. Martínez & F. García. Butll. Soc. Micol Valenciana, 6. 2001: 249-250).
Mattirolomyces terfezioides grows mainly on the sandy soils deposited by the Danube, slightly alkaline to neutral ones, high in humus, and that is why it is also called “sand truffle”. This sweet truffle grows in semi-humid climates, although it is included within the “desert truffles”.
We found some M. terfezioides in Robinia pseudoacacia mixed forest, within the Kiskunság National Park, thanks to Andrea Gogan, from Szent István University. It was a day dedicated to finding “szarvasgomba” (truffles), to make an inventory of species. We had the help of Bagi István, Zsolt and their truffles dogs. Although M. terfezioides is a truffle that comes to the surface when ripens, when they are detected by dogs before cracking the surface of the ground, they are of better quality
They are harvested for commercial purposes in Hungarian and were sold for 35.000 Forints a Kg. (about 130 Euros a Kg.) in Hőgyészi fair, about the same price as theTuber aestivum f. uncinatum.
Mattirolomyces terfezioides are regular globose shaped with the size between 1-20 cm. Peridium very thin, white color at first, then becoming ochre, when ripens. The gleba is ochre with white veins. They have a softer and more watery consistency than Terfezias, going off earlier. Slightly aromatic odor at first, becoming unpleasant when ripen. Very sweet and persistent taste.
We tasted it in several desserts and liked it very much, but we must use it in small amounts because its sweetness can become cloying.