I have a wonderful Chicken Quesadilla recipe that involves cooked and shredded boneless/skinless chicken breast. I generally poach the whole breasts in a frying pan with chicken broth or a little water, and it comes out quite tender and easy to shred.
When I start by defrosting frozen chicken, I end up with a thick liquid in the bag of chicken. Thinking that it would be a reasonable broth substitute, I have several times tried poaching in that liquid instead of the broth or water. But, each time a strange thing happened: the liquid seemed to curdle, looking a bit like someone had stirred in some small-curd cottage cheese. It's certainly not dangerous, but it isn't very appetizing.
What is it in the liquid from a defrosted chicken breast that curdles when heated? Is it inherent in the chicken, or something added at the processing plant (I generally use Perdue)?
