How long does a white truffle last?
Agreed. I would tightly wrap, put in any type of airtight ziplock or jar.. and put in the fridge (not the freezer). Will be no problem keeping a few days... even up to a week, so a weekend is no problem. Don't forget to have a little shaved truffle on your bkfst eggs.
There's nothing like having your own truffle. The problem with restaurants is their "portion" is typically a joke... a few shavings... a tease. When you have your own, after you've eaten half of your pasta and the truffles you shaved on top are basically gone... no problem, just shave some more. Im jealous.
From “The Joy of Truffles”, Benedikt Taschen Verlag GmbH – 1998:
Truffles are up to 73% water and ‘lose their savour’ i.e., shrink by about 5% of their bodyweight per day – a reason to slow down the loss by any means possible. Your wrap the truffle in kitchen paper, close it in an air-tight jar, and put it in the fridge. The paper should be changed at least once a day, so that the truffle stays dry and does not go moldy or bad.
An old but effective strategy is to dip the truffle in wax. In this way, neither moisture or aroma can escape. A method used in the 16th century to bring the white delicacies intact from Italy to the French court. Both white and black truffles can be kept from three days to a week, but they taste best completely fresh.
If you keep it tightly wrapped, it'll last a few days.
I visited a truffle hunter in Piemonte, he kept his wrapped and in a chest freezer.
NOTE: You don't slice white truffles, you shave them. When sold as a "truffle shaver," the tool sometimes costs over $25, when sold as a "chocolate shaver" usually under $10. Given the cost of white truffles, you'll recover the investment the first time you use it.