e-Cig Liquid goes by many names: e-Liquid, e-Juice, Vape Juice or sometimes just juice. But what is it exactly?
e-Cig liquid is a mix of Propylene Glycol (PG) and Vegetable Glycerol (VG). These are your base ingredients. They are denoted by a ratio such as 50 PG / 50 VG, or 70 VG / 30 PG. Sometimes you see 100% PG or 100% VG. Propylene Glycol holds flavor better but is rougher on the throat, called a "throat hit," but some vapers like this because it's closer to the feeling of smoking.
VG has a slightly less potent flavor but is much smoother on the throat.
So these ratios give you an indicator of the potency of the flavor, as well as how it's going to fee when you inhale. But note that these are guidelines, plenty of manufacturers make VG only e-Cig liquids that are packed full of flavor, or PG that is smoother on the throat. The best way to find out is to try!
Once the base is created, the liquid nicotine is added. The nicotine used in e-liquid is USP, pharmaceutical grade and is extracted into either a PG or VG base or combination of both. While the nicotine is extracted from tobacco, nicotine itself does not pose the same health risks as tobacco. It can, however, be dangerous to ingest e-Liquid or to leave large amounts on your skin for prolonged periods of time.
The flavoring used in e-Liquid is the same type of flavor extracts used in your food and drinks! The flavor is extracted into usually a PG base. Sometimes there is a small amount of ethyl alcohol used to extract the flavor but this evaporates rapidly in the air and when exposed to heat. The flavors are mixed into the PG/VG base and nicotine in different ratios to create simple flavors like strawberry to complex dessert flavors like German Chocolate Cake or Tiramisu.