Jerky cure?

I got myself a nice little dehydrator over the winter, and have been experimenting making beef jerky and stuff.

The company (Nesco) also sells a jerky gun, which I bought, which is great for making consistent-size jerky, and it came with some flavoring packets and also "jerky cure". You're supposed to put both in. I did, it works fine. I can make my own spice mix, but I was curious about the jerky cure - it tastes suspiciously like salt, and from what I know of curing meats (I'm no expert, but...) salt is the age-old preservative. There are more refined chemical compounds, I'm sure (BHA, BHT anyone?) but is the jerky cure simply salt? There's no ingredient list. What else might be in there?

plain salt and pepper is my favorite for jerky, but you can use chili powder or soy, brown sugar etc I suppose you could use some liquid smoke too but personally that is why I DON'T like commercial jerky. I like to taste the meat.

I started off using steak strips (the wrong cut, but I was too lazy to deal with marinating flank). I moved to hamburger, with spices - it's just easier. However I like "real" jerky, strips of steak. What cut do you use?

also "london broil" trim all visible fat and partially freeze and it will be way easier to cut thinly. I used to brine it but just salting works faster!

I have never used hamburger - and would be concerned about fat unless it was extremely lean. Not sure I would like the texture for plain eating, but it might be fine in recipes?

My concern with fat is because it goes rancid fast.

Now my way is pretty high in sodium, and technically you can dry meat just plain - heck we bought some carne seca with NO flavor or salt (although they threw in a little packet of chili sauce) in Mexico just a couple weeks ago...so you need to keep experimenting and adjust to your needs and tastes.

93% if I can find it, at least 90%.

Rancidity is the biggest problem, plus it makes drying it problematic. I tried sandwich steaks but they were unsatisfying. I love to cook with London Broil - it's cheap and flavorful; I could try that. Most recipes called for marinating flank steak, but I'm too impatient for something like that.

Actually, burger (I'm using 90+% lean Angus Steak ground) isn't bad - it's easy to work with. That said, I like chewing a good strip of jerky, which you won't get with burger.