I don't think that you can change the format or bit rate of a file when you burn a CD. In other words, what ever format or bit rate the file was ripped at is what it will be when you burn it to a CD. In order to have it be a lossless format, it would have to have been ripped that way to start with. Of course, if you are burning directly from a CD, you will just get an exact copy of the original.

Anyway, I believe that is the way it works. If I'm wrong someone please correct me.