I also make my own. I was able to pick up a Nesco Dehydrator for around $30.00. I think it is important to get the kind of dehydrator where the fan is on TOP, not the bottom. I've been told the ones with the motor on the bottom tend to burn out when used primarily for making jerkey type items.
I second the recommendation for putting the dehydrator OUTSIDE. There is nothing quite so awful as the smell of liver as it's being dehydrated.
I purchase rather large containers of beef liver for just over $1 at my local grocery store (I tried chicken liver, but it just doesn't work as well). I cut it up into uniform sized pieces, put them on the dehydrator trays, and turn it on. I "cooked" mine overnight, but was told that it should be done for 24 hours to make sure to get all the moisture our to prevent molding. I simply kept mine in the refrigerator... and freezing also works to keep it fresh. If all the moisture is out, you wouldn't need to refrigerate.
Liver can also be dehydrated in the oven. You'll need a cooking screen, as you don't want the liver to sit in it's own juices. You'll want to place a cookie sheet or pan on the rack underneath to catch the juice, or your oven will get rather messy. Leave the oven door open and bake at 200*F until the liver snaps like a popsicle stick when tested.
IMO dehydrated liver treats are pretty much worth their weight in gold. Apollo isn't all that interested in other training treats (which I'm told is not uncommon with a male Rottie), but he'd do ANYTHING for dehydrated liver! Plus, I feed raw and just feel better feeding a natural treat, too!
