Angela wrote-
<< Of course you can separate proteins and know which ones you have a
reaction
 to. It is a laboratory procedure where they test for antibodies to each
 of this proteins in your blood. My son tested allergic to the three of
 them (lactoalbumin, casein and betalactoglobuline) but you can be
 only allergic to one of them (and it is the most common case) being
 casein the most frequent.

I am trying to understand this further.  What kind of symptoms does you son
have?  Are they more behavior?  Digestive?  Or hives/anaphylactic?  Paula