When I use a <meta name="keywords" content="Release Notes, Product"/> the file properties in Acrobat Reader show quotes around the keywords.
Is there any way to remove these quotes?

I don't know, as we don't add them. Strangely if you add quotes yourself around the value, Acrobat displays three quotes!

<meta name="keywords" content="&quot;Release Notes, Product&quot;"/>

"""Release Notes, Product"""