Accessing Cookies in HTTP Response for Authentication

How do I access cookies sent from a server in an HTTP response with Ionic? I am using an Express server with cookie-based authentication, but I am not receiving any cookie headers in my response. I also tried using ngCookies but am getting null.

    return this.http.post(loginURL, {withCredentials: true}) 
      .map(res => {
        console.log(res);
        return res.json()
      })
      .subscribe(data => {
     });

https://www.google.de/search?q=angular+2+http+cookie+get&oq=angular+2+http+cookie+get