What's in an e liquid or vape juice? The main ingredients are propylene glycol (PG) and vegetable glycerine (VG). These are solvents that are basically used to dissolve and carry the other ingredients. What Is in Vape Juice? [Key Ingredients Explained] Grey Haze UK Exactly what is e liquid Jacks E Liquid Vape Juice Ingredients: All You Need to Know E Liquid is made up of four basicingredients; water, nicotine, flavorings, and a propylene glycol or vegetable glycerin base (or sometimes a mixture of PG and VG). Nicotine Cigarets ingredients Acetaldehyde used to