Ranch is right. changing a recipe can change the delicate PH balance that means the difference between safe canned goods, and botulism. You do NOT want to tangle with botulism. Up until recent innovations, botulism poisoning use to be nearly 100 percent fatal. Even with modern medicine, you get a big enough dose and they still might not be able to save you.For shelf stability and safety reasons, stick to tested recipes for canning meats, soups, etc. (I mean some seasoning variation, etc. won't make a huge difference, but don't get ambitious and veer off recipe too far). Those websites rebel gave you should have plenty of good ones.
If I am going to add extra seasoning or anything like that, I always add extra acid to make up for the dilution.