Why does inside of cooked canned chicken always taste cold?

The product you're using is made of "mechanically separated meat", aka "white slime". It's produced by pumping or centrifuging ground chicken bones through a sieve to separate remaining bits of flesh. While chemically similar to regular meat, mechanically separated meat has lost its meat-like texture during the separation process. It tastes mushy because it is mush. Frying it will dehydrate and brown the surface, giving it a more palatable texture, but no amount of cooking will approximate the texture of regular chicken; it had that texture once, and then industrial food processing was done to it.

The pink color has nothing to do with rawness, or with chicken-ness for that matter. That product is designed as a lower-quality, less-expensive alternative to tinned formed pork products like Spam. In order to "sell" it as a Spam substitute, colorings are added to make it look approximately like ham (or, at least, less like mechanically separated chicken).

Incidentally, it is also possible (though perhaps harder) to buy tinned chicken which is just tinned chicken, not mechanically separated meat slurry. The texture of that is basically the same as that of boiled chicken.