The Bread and Butter of E-Liquid: VG and PG
We all know that besides flavoring (and nicotine) there are 2 base ingredients that make up nearly 90% of most E-liquid in a bottle: Vegetable Glycerin (VG) and Propylene Glycol (PG). These two have made up the basic anatomy of a bottle of E-liquid since anyone can remember vaping, and the medical and chemical effects have been discussed and gone over countless times since then. But what exactly do these two ingredients do to effect your vaping experience?
Let's start with Vegetable Glycerin, VG is a viscous liquid that is produced from plant oils, by itself it has a thick and translucent consistency. VG makes up the 'bread and butter' of a bottle of E-liquid, and is mostly flavorless, in the last few years most juice makers lean more towards a VG majority when it comes to the ratio in a bottle, this is mainly due to the fact that VG will smooth out and equalize the flavor of an E-liquid, however cotton has a very difficult time absorbing VG by itself. Also the vapor produced by your vaporizer is mostly VG. It also allows the E-liquid to be subtly sweeter, as your body metabolizes the liquid like sugar, if you were to vape straight VG (which I've done, for science purposes) it pretty much just tastes like sugar water. VG by itself is not overly capable of holding onto the flavoring in E-liquid, as it's too thick and the flavoring won't hold to it. Which leads us to the requirement for it's other half.
Propylene Glycol or PG is a synthetic organic compound, it's normally used in a large variety of solvents alongside water and other chemicals. PG is much more fluid than VG, and is used much more widely in food processing. PG is usually found in much lower quantity in a bottle of E-liquid, as it's reception upon inhale is more harsh than VG. However PG is what allows the flavoring to mix into the whole bottle of E-liquid as well as actually wick properly in your coil or cotton, and isn't totally necessary but gives the juice more balance and consistency. Some individuals are actually allergic to PG and hence from time to time you'll find 'PG Free' E-liquids, this is a tricky claim however as many base flavorings are diluted with PG to allow it to mix well with a bottle of E-liquid. PG by itself has a sweet taste, but the flavor and vape is harsh and generally unpleasant, as well as producing very little vapor. PG is more of a medium for flavoring in modern E-liquid, and in general is found in quantities of less than 30% compared to VG.
The ratio of VG to PG is quite important but also sort of irrelevant when choosing a new flavor. It's important to understand the difference between the two and that a different ratio will in fact change the flavor of a bottle of E-liquid. If you were to buy your favorite flavor with an 80VG to 20PG ratio, it would probably taste great, however switch that around to 80PG and 20VG, the flavor will probably be overbearing and aggressive. Now that's not to say that the difference is drastic, a 75VG/25PG compared to a 85VG/15PG E-liquid will be nearly indistinguishable from each other, which is why it's almost irrelevant as the vast majority of E-liquid manufacturers won't stray far from that accepted formula.
In conclusion, flavoring (and nicotine) usually makes up less than 10% of a whole bottle of E-liquid, this is done so that E-liquid is actually vapable, so the majority of what you vape is VG and PG. It's like the difference between a shot of hard liquor and a tall mixed drink. Which is why it's important to understand the difference and how the ratio can effect your quality of vape.
- Aiden Fedyk