The maximal optical density point, Amax, is reached when 7.0 ml
of a carrageenan solution (0.5%, w/w) have been added to 10 ml of
a gelatin solution (0.5%, w/w). With taking into account a dilution
factor, the -carrageenan/gelatin w/w ratio, Z (gcar/ggel), at Amax is
given by