Observations: Is the low pH of carbonated drinks what causes its effect on meat?

Raw chicken in coke:

-       Piece of meat has turned more whitish in colour and has increased in size

-       The coke has separated to form a yellowish transparent solution and black residue at the bottom

Raw chicken in diluted phosphoric acid(same pH as coke):

-       piece of meat appears to have increased in size slightly and has turned a colour slightly whitish(more than before)

-       solution does not appear to have changed

Raw chicken in root beer:

-       Piece of meat has turned more whitish in colour and has increased in size

-       The root beer has separated to form a yellowish transparent solution and black residue at the bottom

Raw chicken in dilutes phosphoric acid(same pH as root beer):

-       piece of meat appears to have increased in size slightly and has turned a colour slightly whitish(more than before)

-       solution does not appear to have changed

Cooked chicken in coke:

-       piece of meat has turned black in colour

-       solution does not appear to have changed

Cooked chicken in diluted phosphoric acid(same pH as coke):

-       meat appears to have increased in size slightly

-       solution does not appear to have changed

Cooked chicken in root beer:

-       piece of meat has turned black in colour

-       solution does not appear to have changed

Cooked chicken in dilutes phosphoric acid(same pH as root beer):

-       meat appears to have increased slightly in size

-       solution does not appear to have changed

Raw pork in coke:

-       Piece of meat has turned more whitish in colour and has increased in size

-       The coke has separated to form a yellowish transparent solution and black residue at the bottom

Raw pork in diluted phosphoric acid(same pH as coke):

-       meat appears to have turned a color slightly whitish.(more than before) and appears to have increased slightly in size

-       the solution has a yellowish tinge(probably due to diffusion of blood from the piece of meat into the solution)

Raw pork in root beer:

-       Piece of meat has turned more whitish in colour and has increased in size

-       The root beer has separated to form a yellowish transparent solution and black residue at the bottom

Raw pork in dilutes phosphoric acid(same pH as root beer):

-       meat appears to have turned a color slightly whitish.(more than before) and appears to have increased slightly in size

-       the solution has a yellowish tinge(probably due to diffusion of blood from the piece of meat into the solution)

Cooked pork in coke:

-       There is a white residue found floating at the top of the solution

-       The piece of meat has turned black in colour

-       The solution did not appear to have changed

Cooked pork in diluted phosphoric acid(same pH as coke):

-       meat appears to have increased slightly in size

-       solution does not appear to have changed

Cooked pork in root beer:

-       piece of meat has turned black in colour

-       solution does not appear to have changed

Cooked pork in dilutes phosphoric acid(same pH as root beer):

-       meat appears to have increased slightly in size

-       solution does not appear to have changed