Cook's IllustratedJane Bowers, head of the Department of Foods and Nutrition at Kansas State University, says salt is used in meat processing to extract proteins from muscle cells and make these proteins more viscous:
“Brining turkey causes a change in the structure of the proteins in the muscle. They become sticky, which allows them to hold more water.” Citing a similar example, she says frankfurters without sodium are limp. “It is the salt that gives hot dogs their plumpness,” she says.
Tina Seelig, scientist and author of The Epicurean Laboratory (W. H. Freeman, 1991), says salt causes protein strands to become denatured, or unwound. This is the same process that occurs when proteins are exposed to heat, acid, or alcohol. “When protein strands unwind, they get tangled in one another and trap water in the matrix that forms,” says Seelig.
And Dr. Bill Schwartz, director of technical services at the Butterball Turkey Company, adds that when these unravelled proteins are exposed to heat they gel — much like a fried egg white — and form a barrier that prevents water from leaking out of the bird as it cooks. The capillary action that draws blood out of the meat and gives it a milky-white color also helps the brining solution penetrate deep into the meat, according to Schwartz. This accounts for the pleasant salty flavor even of the inner breast meat.
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