The Collaborative International Dictionary of English v.0.48:

Saltness \Salt"ness\ (s[add]lt"n[e^]s), n.
   The quality or state of being salt, or impregnated with salt;
   salt taste; as, the saltness of sea water. In the sense of
   having salt content, saltiness is more commonly used.

   Syn: saltiness.
        [1913 Webster + PJC] Saltpeter

The Collaborative International Dictionary of English v.0.48:

saltiness \salt"i*ness\ (s[add]lt"[-e]*n[e^]s), n.
   1. The quality or state of containing salt; salt taste; as,
      the saltiness of sea water.

   Syn: saltiness.
        [1913 Webster + PJC]

WordNet (r) 3.0 (2006):

saltiness
    n 1: language or humor that is down-to-earth; "the saltiness of
         their language was inappropriate"; "self-parody and
         saltiness riddled their core genre" [syn: saltiness,
         coarseness]
    2: the taste experience when common salt is taken into the mouth
       [syn: salt, saltiness, salinity]
    3: the property of containing salt (as a compound or in
       solution)