www.scribd.com/doc/11337868/Optimal-Conditions-for-the-Growth-of-E-Coli has some clues as to what promotes growth:
"However, because of the mechanism of osmosis, extremely high levels as well as complete absence of salt could be lethal to E. coli bacteria."
So what does extremely high levels of salt mean? Is it still edible after that? Page 11 shows the results of the salinity test, and all concentrations show the same result. So salt did not seem to work. "E.coli is able to tolerate added salt of up to 10% concentration."
Sugar did not work either: "None of the concentrations of glucose had any affect on the growth of E.coli."
pH is more interesting: "E.coli was able to tolerate an acid of pH 2.4 more easily than a base of pH 11.6." The pH of apple cider vinegar is typically between pH 4.25 and 5.00. So soaking in vinegar would not really help, but making it basic would help. Perhaps Lemon juice might help as that's a pH of 2, thus more acidic that Vinegar, and below the 2.4 threshold, so ground beef ceviche anyone?
Making it more basic: Ammonia has a pH of 11.6, so this is why CAFO meats are soaked in it. Would it still be edible after that? Would you want to eat ground beef that's been soaked in Ammonia? Maybe it could be washed off, but what affect does it have on the meat and are there residues and remnants of reactants to Ammonia?
And if you go to a normal restaurant, do you think they'd even bother to soak ground beef to wash away the Ammonia, or does it go straight onto the grill?
Temperature: "largest colonies were present..at 37C." ... "as the temperature increased from 37C to 50C, the size and number of colonies decreased." Hence the recommendations to keep meats very cold, and cook until the internal temperature is high enough to kill any pathogens.
"E. coli bacteria can survive freezing temperatures" so all freezing would do is to prevent growth, and keeping meat cold just limits the growth.