Ground meat simply exposes more surface area to bacteria. They put trim and I assume they also put cuts of meat that haven't sold in the grinder. They don't put organ meats in the grinder unless you specifically ask. Can you imagine the outcry if they did?

Organ meats have way more vitamins than muscle meat so some cultures through the muscle meat to the dogs.

After my last day of work, before leaving Chicago I go to Whole Foods and purchase about 3 pounds of their grass fed ground beef. I'm not sure if it is "grass finished" too, but I'm also not that much of a Paleo Hipster© to care.

HOWEVER, Jewel-Osco is now selling grass fed AND finished beef!!! They run out SO quickly though, I've only gotten the ground beef burger patties twice so far. I don't think they've been selling it for longer than a month.

I doubt they just throw in liver in there. Most of the time they just use the less tasty stuff and add spices. Many organs are high in cholesterol or retinol and you know how the government thinks about that (cholesterol = deadly, retinol = birth defects and cancer).

Health-wise I think it doesn't matter much, since its just a different part of the animal but most of the time it's muscle meat. Maybe the higher percentage of saturated fat is beneficial though.

Cost-wise it's better. When I ate plenty of meat I always bought ground meat and my butcher also pushed me to do so because I'm a student and they didn't want me to spend all my money in there :).

Taste-wise I personally think a piece of lean meat in the oven is 100x better than ground meat, especially since it's not very tasty to cook ground meat lightly : raw meat is tasty, but not in ground meat IMO. That may be just me. I love raw meat but I don't know many people who agree with me (most people around me love burnt meat). Right now I don't ever eat ruminants except for the occasional liver, as high protein diets tend to make me hypoglycemic and a bit tired (this was not the case for the first 6 months on paleo, since the winter I get atopic dermatitis if I eat a steak with veggies).

I'd avoid ground CAFO meat if at all possible. It comes from multiple animals, and is mixed in. That's the best way in the world to take bacteria, which lives only on the surface of meat, and spread it all over all of the meat and give it lots of surfaces to infect. So if you eat it rare, you're going to ingest live bacteria.

This is why the meat processors used pink slime (some still do) which uses ammonia to kill off e. coli. Instead of keeping the machines and killing floor clean, and prevent the contents of the intestines of cows from infecting the meat itself, because that would mean slowing down the production line. Their inclination is to use chemicals to kill the bacteria instead.

If you must eat CAFO ground meat, have it well done.

If you're getting it from a trusted source, it's probably ok.

CAFO ground meat is cheaper because it's mechanically separated, so they can pull all the tiny bits and pieces off the bones. There's no organs in it.

If you want, get your own meat grinder, or use a food processor to chop up liver, and mix it in with ground meat from a trusted source, or grind your own after washing off the surface.

I think grassfed ground beef is better than leaner cuts, because you get more fat that way. Whole Foods in my area mixes all the trimmings with the ground beef, so the ground beef has a good amount of fat! With CAFO products, I would choose the leanest possible.