What's a Truffle?

From The Robb Report comes a very nice article about a Tennessee elephant trainer who is now training dogs to find truffles which are valued as high as $1,000 a pound.

First, he creates what he calls “scent tubes.” These 2-inch pieces of PVC pipe are filled with cotton balls and injected with truffle oil through holes drilled into the pipe. From there, it’s a three-step process. Step one involves imprinting the truffle scent. Sanford presents the tube to the lagotto romagnolo; when the dog smells it, Sanford immediately puts a treat in its mouth. This teaches the dog that this particular scent will earn it a reward. The next step involves having the dog wait inside while Sanford hides scent tubes under piles of leaves outside. Once the dog is let outside and smells the tubes under the leaves, Sanford again rewards it.

The final step is the most critical. Because truffles are buried underground, “I need the dog to give me an overt signal that says what you’re looking for is right there.” To that end, Sanford buries the scent tubes underneath the ground near a tree because that’s where truffles are always located. When the dog acknowledges it, Sanford doesn’t reward it. Instead, he points to the ground, asking, “Where is it?” Eventually, the dog learns to paw the ground at the location where the tube is buried. Then, Sanford moves the dog away and carefully digs up the tube (and in real-world scenarios, the actual truffle). Only after Sanford has extracted the truffle does the dog receive a treat.