We have been using 9-10% sterile saline solution (0.9%) in our mixes for months now.
--Do NOT use any kind of "table salt" or natural salt (even without added iodine, etc., natural salt is not 'pure salt' and has many unknown impurities. If you're going to make a solution, use only USP Sodium Chloride
--Agree 100% with Blkwdw86 - salt will NOT dissolve in VG or PG. It must be dissolved in distilled water first.
--Adding sterile saline solution (.9% dilution - commonly available for hydration; irrigation of wounds & sinus/nasal passages; and for use in nebulizers for lung treatements) will NOT add a salt taste. We have never tasted 'salt' in any of our mixes or when we vape the base without flavoring.
--Adding sterile saline solution will enhance flavors and help to hydrate mouth, nose & lungs.
Ours is from a local drugstore/pharmacy (there are dozens of options on Amazon) - maker: Baxter
The label:
Baxter
Not for Injection
0.9% Sodium Choride Irrigation, USP
Each 100 ml contains: 900 mg Sodium Choride, USP. No antimicrobial agent has been added. pH 5.5 (4.5 to 7.0) Osmolarity 308 mOsmol/L (calc.). Sterile, nonpyrogenic,
Pour Bottle. Isotonic solution for irrigation only.
(the reason they have to say it's for "irrigation only" is because this is not the type of 'saline solution' to be used via IV. Also, there's no antimicrobial agent added. PG & VG are antimicrobial
)
--We've used three different 'brands' of .9% sterile saline solution; none had an odor.
--How much salt are we talking in laymans terms? If one used a .9% solution at 9-10% in their juices, they'd be using approximately 1/4 teaspoon of pure salt spread throughout 1 liter of finished juice (1000 mls - so over 33 30ml bottles). I've read of folks using much less than 9-10%...but we're very happy with that percentage.
--We are not the only vapers that use sterile saline for DIY! We discovered it in this thread:
http://www.e-cigarette-forum.com/forum/diy-e-liquid/268760-diy-master-techniques-flavor-add-ons-em-vw-bw-mts-acv-ect-2.html#post9340969 (starting around Post #49) ...and we're very happy we did.
In fact, there's no doubt in our mind that it's one of the 'proprietary ingredients' used by juice vendors that makes their flavors "pop".