If you’re an avid vaper, you’ve probably come across some e-liquids that seem to change colors, whether still in the bottle or while vaping. Don’t be worried, you aren’t getting a poor quality e-liquid. There are a couple of reasons why this might happen.

OXIDATION
Nicotine is a very sensitive substance that can react with other ingredients like air, light, heat or any other ingredients it may be mixed with. The e-juice containing other ingredients can, over time, become darker even if stored in a cool area. Some companies introduce preservatives or stabilizers to prevent this. Since oxidation is a natural chemical reaction it doesn’t alter the quality or taste. Many people have mistaken this for bad product and discarded a perfectly good e-liquid because they associate the color change to a spoiled product. It’s much like what happens to an apple or potato when you peel the skin away. The pulp is exposed to oxygen in the air resulting in a brown color that occurs over time. Oxidation occurs even faster in the clearomizer, when exposed to high heat.

CARAMELIZATION
Vegetable glycerin-based e-liquids are a bit sweeter that propylene glycol types. With the introduction of high heat, it causes the glycerin (sugar) to breakdown and caramelize on the coil. This “gunk”, as it’s formally known in vaping circles, can stain the e-liquid causing a darker browner effect as the liquid gets lower. This type of caramelization does affect the quality and taste. It’s recommended that both the tank and clearomizer are thoroughly cleaned on a regular basis before refilling. This, however, results in frequent changes of the coil and wick of your atomizer. The gunk build-up is closely related to the sweetness and viscosity of the e-liquid. In other words, a thicker, sweeter e-juice will caramelize quicker than a PG-based tobacco e-liquid.

Whether caused by oxidation or caramelization, a change in color doesn’t pose a health hazard. The more you dwell in the vaping circle, the more you’ll experience the color changes. Knowing what causes it helps you save your precious e-liquid(s).