There are various species of truffles within the Fungi kingdom, but only true truffles are part of the genus Tuber. The most notable and commercially viable truffles include:

Black Truffles

Earthy, aromatic, intense, sexy and intoxicatingly fragrant - the Black Truffle evokes a wide variety of emotions and senses when experienced fresh and only days from the farm. The primary product of Piedmont Valley Truffles, the Tuber melanosporum has a rounded shape and varies in size from as small as a marble to larger than a softball.

With a season running from December through early March, they are considered by my gourmets to be the finest and most exquisite of all truffles. Varying from reddish brown to black in color, depending on maturity, the skin (peridium) is grainy with smoothly rounded pyramidal bumps or facets. Inside, when mature, the flesh (gleba) is a violet-brown or gray with concentrated slender white veins throughout.

The Black Truffle is best prepared when slighted cooked or heated, but can be equally enjoyable sliced raw over a variety of dishes. Historically harvested in Italy and France, the growing region has been greatly expanded due to natural cultivation and modern farming techniques as those employed by Piedmont Valley Truffles.

White Truffles

The White Truffle is extremely rare, with no known means of cultivation and only a few tons produced worldwide yearly. They are harvested predominately from Northern and Central Italy. The season is relatively short, starting in early October and continuing to late December, with a peak in late November and December. Not typically larger than a golf ball, they are flat and irregular shaped with the smooth skin an olive-yellow-grayish color. The flesh is tan and marbled yellow-white with thin pale veining. White Truffles are best eaten raw, often shaved over hot dishes, with cooking destroying their intense flavor and aroma.

Summer Truffles

More common and less expensive than the prized Tuber melanosporum, the Summer Truffle does make for a less flavorful substitute outside of the regular Black Truffle season. Slightly crisp and nutty in taste, Summer Truffles enjoy a very long season running from May through November, with the peak in late July to mid October. Late season Summer Truffles are usually more flavorful than those from earlier in the season. Their skin is tougher than the Black Truffle, covered with large protruding triangular bumps, and insides are pale beige with thin white venation.

Chinese Truffle

The Chinese Truffle has been gaining popularity recently in the United States due to its abundant supply and dubious marketing tactics by unscrupulous dealers. It is often misleadingly sold as the much higher priced Black Truffle, given its almost identical exterior appearance, but lacks any discernable taste or flavor. When mixed in with Tuber melanosporum, Chinese Truffles will absorb the aromas and become even more difficult to identify. The interior veins are more numerous than the Black, and they do not turn red when exposed to air as do the Black Truffle. One of the best ways to distinguish the Chinese Truffle from the Black Truffle is under a magnifying glass where the small surface warts will be pointed and pyramidal as opposed to smoothly rounded.

Oregon Truffles

Oregon Truffles grow naturally in the Pacific Northwest and are harvested by hand raking the ground cover in known producing areas. There are various types of fungi broadly classified as Oregon Truffles, but the most prevalent have an ivory blotchy-brown skin with a pale interior flesh. The season lasts from early October to late November. There has been much debate among epicureans regarding the comparison, in terms of taste and aroma, to other truffle varieties such as Black. Although James Beard, an Oregon native, is an ardent fan - others are quick to point out that they have very little flavor or value as a culinary enhancement.

Brumale Truffles

Although very common in Europe, Tuber brumale is not prevalent in the United States. Often called the Fall Truffle, Brumale is very similar in external appearance to the Black Truffle, although the interior is smoky grey and distinguished with thicker and more widely spaced veins. The season is similar to the Black Truffle, and they are often used in the processing of various truffle products. The aromas are often pungent and broadly range from a heavy musk to almost no smell or taste at all.

Burgundy Truffles

Also known as the Hooked Truffle in Italy, the Burgundy Truffle is often considered a close relative to the Summer Truffle. With a later season running from early October to December, the Burgundy bears a similar exterior resemblance and aroma, with a slightly stronger taste, to Tuber aestivum, although it has a darker chocolate gleba at maturity. Like Brumale, the Burgundy Truffle is not readily available in the Western Hemisphere.