The main ingredients in eliquid or ejuice are vegetable glycerin, propylene glycol, natural and artificial flavorings and nicotine.
Vegetable glycerin also known as VG is a clear, colorless, thick liquid when cool that has a naturally sweet taste. It is made from palm oil or coconut oil by the process of hydrogenolysis, which removes the fatty acids, leaves just pure vegetable glycerin. VG is the main ingredient that produces the vapor we see in electronic cigarettes, the more VG% the thicker the vapor or clouds. I should also note that the more VG% used the less intense the flavor will be. There are many uses for VG other than in eliquid for instance soaps and cosmetic products. VG is completely edible. It is considered GRAS (generally recognized as safe) by the FDA.
Propylene Glycol also known as PG is a much thinner liquid than VG, but not as thin as water. It is virtually colorless and odorless. PG is also known as 1,2-propanediol or propane-1,2-diol with the chemical makeup of C3H8O2. In chemistry, it is considered an organic compound. PG acts as the main flavor carrier in eliquids and at higher percentages can produce more of a throat hit. Although not originally used in electronic cigarettes, PG has been used in many household and food products including cake mixes, sodas, salad dressings and cosmetic products as well as medical uses. It is also considered GRAS (generally recognized as safe) by the FDA.
Many types of flavorings are used in electronic cigarettes including natural extracts and artificial flavor aromas. Although flavorings are not required to produce vapor, flavorless eliquids are very bland and unsatisfying. Some of the major brands of flavors used in ecigs are The Perfumer’s Apprentice, Flavourart, Flavor West and Capella. Some other brands include Nature’s Flavors and Medicine Flower which are natural extract companies. Artificial flavors have to be FDA approved for human consumption before being allowed on the market.
GRAS Substances (SCOGS) Opinion: Propylene Glycol
https://www.fda.gov/food/ingredientspackaginglabeling/foodadditivesingredients/ucm094211.htm
GRAS Substances (SCOGS) Database
https://www.fda.gov/Food/IngredientsPackagingLabeling/GRAS/SCOGS/ucm2006852.htm
Most nicotine used in the manufacture of eliquid is sourced from tobacco, however it can also be found naturally in potatoes, cauliflower, green tomatoes and eggplants. Any plant in the nightshade family contains nicotine.
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