Change Meta Tags dynamically angular

I'm trying to change the content of the meta tag Keyword dynamically. I have:

<meta name="keywords" id="selKeyword" content="">

and I'm doing it as follows:

$("meta[name='keywords']").attr("content", "hello");

I put a display in the meta keywords and saw that the hello has been set, but when I go to view source code I see that the content is still blank.

Is there any way around this?

EDIT: I did not have to do this in my project any more, but in none of the answers did I get the solution done. But I no longer need it. Thanks to all who helped me