There definitely IS a max you can absorb but it varies from person to person. While your body may not exactly say "fuck it" and stop absorbing protein, it can only absorb it at a certain rate, and only while it's still IN your GI tract under the right conditions. Depending on how much you eat, your rate of gastric emptying, and how fast your GI tract moves food through it, you may not have time to absorb all the protein you eat before it's pooped out. As was mentioned before though, if you're eating 5-6x a day, unless you're a pro bodybuilder size, 40-50g's per meal should be plenty.