The body can ABSORB a LOT of protein in one meal - the bodies digestive system has the enzymatic capacity to digest and absorb amounts far in excess of what anyone would need (the only time this is not the case is if you have a medical condition which limits your ability to digest the protein or you consume MASSIVE MASSIVE amounts - in which case the bulk of the meal will push the protein through your intestines at a speed that will overwhelm your enzymatic capacity)...
However, the amount your body can actually UTILISE is completely different.... (That is - the amount of protein that your body will use as amino acids for muscle growth and repair, for enzymes, for hormone formation and for other cells and their biochemical processes..). This is related to your lean mass, your metabolism/physiology, your hormone levels, what type of workouts you are doing/how active you are etc etc... And it is very hard to determine just how much your body needs (however - The levels of protein that we all take in actually far exceed our actual requirements)....
eg: a 200 pound juiced man with 8% BF and a 110 pound female with 25% BF may both digest/absorb a meal with 50g of protein in it - but their ability to utilise that protein as PROTEIN will be vastly different.
So, in the case above, if that smaller female ate 50g of protein the excess amino acids that are not needed for their repair/growth purposes will be deaminated and converted to energy via gluconeogenesis... And if you don't need glucose at that point in time, then will then be stored as glycogen (and, in the event that all your glycogen stores are packed up then it will go one step further and be converted to be stored as fat).
But it is safe to say that if you get ~1-1.5g protein per pound lean mass (usually 1.2 to 1.5 to be on the 'safe side') and make sure most of that is from complete forms, and then you divide that evenly over your day then you don't need to worry about just 'how much you can digest/absorb/utilise as will be getting more than enough to give your body all the amino acids it needs...
