the important step is to bring the wet meat to 160 degrees at the beginning of the jerky process. This kills bacteria, whereas bacteria become more resistant if allowed to dry before raising the meat temp gets to 160. Adding a cure helps to ensure bacteria are killed. Drying/dehydrating temp should be maintained to around 140 degrees. If the meat contains fat it probably has an increased propensity for the fat to become rancid, thus having an off taste when stored for extended time. Tho' some of the marinades used will inherently add antioxidants that will help to inhibit rancidity. For me jerky never last more than a couple weeks around here before it's devoured.