If you're buying smoked meats from the deli counter it's likely to contain preservatives etc, so not ideal. If you buy a chicken or joint of beef ( raw) it will have nothing added, so just cook it and allow to cool...... will keep in the fridge for several days. Beef jerky may or may not contain artificial flavourings/preservatives depending on the brand, so either avoid or make your own.
Keep up the good work

Nicki