  We construct a BCS-like model that combines nucleonic pairing correlations
and possible quartic correlations of alpha-type in a single variational wave
function and derive corresponding gap equations. In the approximation of large
logarithms typical for the BCS approach, we show that the system reveals two
possible types of a condensate which cannot coexist. If the alpha-type
condensate prevails at N=Z, the growth of the neutron excess will naturally
lead to the first order phase transition to the nucleon condensates.
