Vegetable Glycerol (of glycerin, glyerine) is a clear, odorless liquid produced from plant oils, typically palm oil, soy, or coconut oil. Palm and coconut oils are natural triglyceride mixtures; each triglyceride is comosed of three fatty acids esterified with glycerin. Vegetable glycerin has a number of valuable application that include cosmetic products, foods, and as a replacement for alcohol in herbal and botanical tinctures.
Vegetable glycerin is produced using an extraction process called hydrolysis. During hydrolysis, oils are placed under the combined force of pressure, temperature, and water. The ester bond breaks and causes the glycerin to split from fatty acids and be absorbed by water; at which point the resultant is further isolated by distillation to increase purity. Purified vegetable glycerin has a texture similar to an oil or syrup due to its organic molecular, specifically, three hydroxyl groups.
Vegetable glycerin used in food applications and E-Liquid is USP grade or over 99% pure and has a sweet taste. Vegetable glycerin metabolizes differently than sugar and is used in low carbohydrate foods for sweetness and moisture. Unlike sugar, glycerin does not contribute to tooth decay.
Many household products, including lotions, shampoo, and toothpaste, contain vegetable glycerin. Glycerin is added to these products because it is a humectant; a substance that attracts moisture to the skin.
The safety of vegetable glycerin coupled with its functional properties has made it invaluable for various medical applications. The hydrating effect of glycerin makes it ideal as a topical remedy for burns. Glycerin is also used in the production of suppositories. A good source to look for is a USP grade, non-GMO, allergan free, kosher certified vegetable glycerin.
Vegetable glycerin based E-Liquid usually contains at least 80% and as much as 92% Vegetable glycerin. This is the ingredient that produces the vapor when the E-Cigarette is exhaled. Approximately 20% of all E-Liquids on the market today are vegetable glycerin based. Vegetable glycerin typically produces more vapor production then proplyene glycol, but has reduced throat hit. IT is also slightly more thicker and slightly sweeter than proplyene glycol. Its increased thickness makes it a culprit in reducing the life of atomizers. Some vapers use a blend of vegetables glycerin and proplyene glycol, most often 80-90% PG and 10-20% VG, and sometimes a 50/50 split VG to PG in their E-Liquid.