This jerky recipe is one I like a lot, but use it as a guide, not dogma. If you want to play with flavors, go for it. Just don't mess around with the ratios of salt, and be sure to let it marinate for at least 24 hours, and up to 3 days. I always use curing salt No. 1 for my jerky, as I like the rosy, hammy effect it produces -- and it's a food safety thing when you dry at lower temperatures.
Slice the duck breasts into roughly 1/4 inch thick strips. Mix remaining ingredients well in a large bowl. Put the meat into the marinade and massage it all around to coat evenly. Pour everything into a seal-able plastic bag or container and set in the fridge. Marinate for at least 24 and up to 72 hours -- the longer it is in the mix, the saltier the meat will get, but the more flavorful it will be. During the marinating process, massage the meat around in the bag to keep all the pieces in contact with the marinade.
Remove the duck from the bag and pat dry with paper towels. Either follow your dehydrator's instructions for making jerky (I dehydrate mine at 140°F), or lay the strips on a wire rack set over a cookie sheet. Set the rack in an oven set on Warm until the meat is dried out, but still pliable, about 6 to 8 hours. Store either in the fridge indefinitely, or at room temperature for up to 1 month.
If you are interested in another flavor of jerky, try my chipotle jerky with duck instead of venison.