White truffles are complicated especially when they’re shipped abroad due to the fact that they need to be washed prior to being shipped to comply with agricultural regulations. So in most cases if you look carefully at the surface of the truffle, You’ll see that there is a substitute that I refer to as truffle makeup. This is a light beige-brownish sand that sparkles due to the added silica included in the mixture. There are examples where people use essence to enhance the truffles aroma, however that clearly cheating. You need to look closely to evaluate the surface of any truffle you buy. /see picture/
This is an example of a truffle from Piedmont that is not enhanced in any way and has a dark brownish dirt on the surface that should be washed away before slicing. You will find from time to time that there’s more dirt on the truffles surface than normal. This is a common place enhancement to gain a little bit more profit, and this is acceptable and normal.