White truffles are on the market from early fall through December. They can be extravagantly expensive, especially when fresh. They have a delicate, intoxicating fragrance. Don’t cook with them, for heaven’s sake! Just use the shavings raw or add them to a dish at the last minute.
Black truffles are also known as winter truffles, and are available fresh now, into the very early Spring. They’re more strongly flavored than the white variety, and work well in risottos and omelets. If you peel the dark bumpy outer layer away, save those expensive parings to flavor sauces or soupy dishes.
Use truffles soon after purchase, and if you can’t, store them in a container containing uncooked rice, cover tightly and refrigerate. The rice will absorb the flavor and taste wonderful. Use the truffles within three days.
Urbani truffles is a recommended source: