See this knowledgebase article. Note, on Apple Support Communities, and any publicly searchable website, it is strongly recommended
you keep your e-mail address invisible from anyone but yourself, and remove the @ symbol if you want to portray it publicly.
Otherwise your e-mail address will easily be pilfered by spammers, and could be used to spoof spam so it appears you are sending it. The net
result is that your e-mail address could be blocked by major internet providers in a blacklist. Apple provides a means of hiding the address
that is set in Apple Support Communities. To hide it, go to the upper right portion of the webpage, and click on your Your Stuff, and select Profile beneath:
The Actions section of the page on the right will then allow you to Edit Profile & Privacy, which you then select:
The Edit Profile section has two tabs, one is Privacy Settings, and you should select that:
Make sure your email is set for "Yourself", and nobody else.
Lastly, save your settings at the bottom of the same page (you may need to use the right hand scrollbar to reach the point where the bottom left part of the page appears thus: