Castle lites safe or not?

I bought a case of Castle lites at a shoprite liquor and to my surprise they all seem to have a sand like substance at the bottom I saved the last 6 pack to try and contact sab so I can show them and ask them what it is that is in that drink, I tried their website multiple times and keep getting an error I searched through all of Google not a single email address for complaints or complements I have the slip, batch number, the actual beers that have the substance and pictures hopefully this will get me a reply from sab soonest.