as far as the heat goes, from discussions I've had woth some jerky makers using Pure Evil, it seems that powders and PE used in the marinade leave a lot of heat behind in the marinade. Adding powders after the meat is drained or adding PE right before drying or even brushed after dry seems to be the best way to get heat on the finished product.
Re: Wally-World meats----look at the labels of all the meats at walmart. I have yet to find a meat, steak, roast, poultry, pork or other sold at the WalMart meat case that is not injected with a 5-15% broth/brine/salt solution. So even $7.50/# could be $8.60/# for the meat. Or look at it that you are paying $7.50 # for broth. It's been a while since Ive checked, but about 5 years ago, I looked at every single meat package and could not find a single one that wasn't injected/enhanced. I asked the person in the white butcher's coat who was stocking the case if I could buy a custom cut. I was told everythign comes in prepackaged in the sealed trays, they don't actually do any processing onsite (Big Surprise There!!!!
)
We are forunate that we have 3 butcher shops in the valley, 2 are in the local grocery stores and there is one independant butcher shop. All fo them breakdown the carcasses in house, grindtheir own beef, make their own brats, sausages, jerky/pepperoni sticks.....
Anyway, just watch what you are buying and know what you are paying for.
As to the heat, powders or PE added after the meat is drained seems to be the most efficient. Has anyone ever tried draining the meat (maybe start the drying process?) cook down/reduce the marinade and use that as a baste? Seems like that would get all the flavors and heat back on the meat, but I'm just throwing ideas out there. I've only done a couple small batches. I'm sure the Pro's have already tried this and will tell us how and why it wouldn't work.