As for your question on Truffle odor: I assume you are using frozen Summer truffle yes? Tuber aestivum?
The short answer: a few weeks to a month or more if you are only having them out of the freezer for short periods of time.
The more complicated answer:
They are pretty darn hardy, but there are a few things to watch out for. Odor does change and degrade over time and the volatiles change in the freezer. We say only keep your frozen truffles to use in training in the freezer for a 1yr. The truffles continue to off-gas during that time and slowly change aroma profile. It may not be detectable to us, but dogs can notice the difference. We talk about it in future lessons but what we are doing in training is teaching the dogs to alert on an array of odors, not just one single volatile compound.
Eventually (and in level 3) we will encourage you to use fresh truffles if you can source them. Your truffle season is coming up, so use fresh in training when you can, and stock up. Summer truffles last a pretty long time fresh- multiple weeks if cared for properly. We have a guide for how to care for Tuber aestivum. I’ll see if we can figure out where to post it, or what lesson it may be included in.
Frozen truffles may look squishy on the inside as freezing and refreezing will breakdown the cell walls, but the volatiles should still be ok.
If the odor starts to get funky at all, throw it out.
Do try to use pieces in training from more than one fruit body if possible. We explain why again, later in the course.
You can also use cotton stored with your frozen truffles in training. This is good as it changes the odor concentration you and Molly are working on. We don’t foresee it being a problem with Molly but remember that changing the density/ intensity of odor changes the scenario and makes it more complicated. It is good to practice with varying degrees of odor.