You should be fine with 48 grams, there are a lot of myths around how much protein your body can process at once and some people are going to quote you a ridiculously low amount like 20-30g. See Myth #2: http://www.bodybuilding.com/fun/hst3.htm

If you go digging around on Google under the term "how much protein can your body process at once" you should find a lot of sources quoted. The extra protein will definately not be wasted, the trick is just not to go overboard on it since the extra calories from the protein could be stored as fat. The truth is there simply isn't any proven limit on how much protein your body can process at once.