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WARNING: This product contains nicotine. Nicotine is an addictive chemical.

Why Is My Vape Juice Turning Brown? - eJuice.Deals

Why Is My Vape Juice Turning Brown?

Have you ever noticed how some e-liquids change color over time? Either a nasty dark brown color in the bottle or a deep amber color in your tank? You may have thought it was the e-liquid going bad or your coil biting the dust, but there’s a little bit more involved than that. In this article, we’re going to fully explain why e-liquids change colors, as well as some ways to prevent that.


This is a very pertinent question for vapers of all experience levels, and the answer might surprise you. Most e-liquids contain some sort of sweetner to enhance the taste of the e-liquid, especially the fruit and dessert flavored e-liquids. As the e-liquid is heated, the sugary sweetness actually caramelizes into a residue to infuse that delicious sweetness into flavors your taste buds can’t get enough of. Over time, the caramelization residue builds up and darkens the surrounding e-liquid. This caramelization residue results in a thicker e-liquid that clogs your coil and results in a burnt coil or a dry hit. The thick e-liquid doesn’t necessarily change the flavor of the e-juice. However, if your coil can’t properly absorb the juice, you won’t taste the full potential of the vape flavor and you’ll think the vape juice’s flavor has changed. This is why some vapers steer clear of certain types of flavors to increase the longevity of their coils.

Another reason your e-liquid might turn brown in the tank is if you don’t use your vape for a while and leave vape juice in the tank. Instead of caramelization in the tank, you have a new problem: oxidation. When nicotine is exposed to oxygen, this oxidation process occurs and your favorite e-liquid will turn brown. While oxidation doesn’t change the quality or the taste of your e-liquid, it can be a bit shocking to pick up your device and see a nasty brown mess swirling around your tank!


Oxidation isn’t limited to old vape juice left in forgotten tanks, but it can also happen inside the bottle. If you haven’t used an e-liquid in a long period of time, you might be a bit startled to see that the e-liquid has changed from a soft yellow to a muddy brown. The consistency will still be the same, but now the liquid looks gross and unappetizing to put into your bottle. Light and heat speeds up this oxidation process, which is why in our last article we recommended storing your unused opened bottles of ejuice in a cool dark place. Granted, this won’t stop the oxidation process completely, but it will certainly slow it down. Nicotine is an extremely reactive chemical, and should be treated with care to ensure your favorite e-liquids don’t turn brown before you’re ready to use them.


As we mentioned before, many e-liquids come with added sweeteners to enhance the flavor. This is especially true of VG-based e-liquids, which are usually the higher number in VG/PG ratios (i.e. 70/30, 60/40, or 100/0). If you’re looking for an e-liquid that doesn’t have added sweeteners or won’t darken as quickly, you can always check for 50/50 ratios or 100% PG ratios. However, check out our other article here, where we mention how Vegetable Glycerin and Propylene Glycol affect the flavor, consistency, and cloud production of many e-liquids.

For the most part, you can prevent oxidation by keeping your e-liquids in a cool dark place. Make sure the area is clean and dark, and ensure each bottle lid is tightly screwed on to prevent oxygen from seeping in.

If you know you won’t be using a particular tank anymore, you should clean out the tank thoroughly. Remove the coil and soak the tank in a cup of hot water. Leave the tank to soak for a bit, then rinse it out and lay it out to dry. Once the tank is completely dry, feel free to store it along with your e-liquids in a cool dry place. This is a good method for tanks that you use regularly as well. How often you clean the tank is relevant to how often you use it. If you use your vape every day, you should rinse out your tank before you change flavors or replace the coil.

Finally, to minimize your favorite e-liquid turning brown, you should avoid mixing flavors in the same tank or the same bottle. This is tempting if you have a particular flavor that you don’t like and you think that mixing it with another flavor might improve the taste. If you want to mix flavors, use a small dish or container that you can evenly blend the different e-liquids. Clean your tank thoroughly before you add the newly mixed e-liquid, and make sure that the e-liquids you’re mixing don’t show any sign of oxidation. If you see that the e-liquid in your tank is already starting to turn brown, don’t add any more liquid until you clean out your tank. The new liquid will turn brown more quickly upon contact with the liquid already in your tank.


We’ve gone over some reasons on why your favorite e-liquid may be going brown. Sweeteners, oxidation, or caramelization buildup can affect your e-liquids, but there are certain methods you can use to either slow it down or prevent it completely. Chances are, your favorite e-liquid will be finished before it can turn brown in the bottle, but there’s still a chance it can turn brown in your tank. Even if you use your vape tank every day, it’s a good idea to clean your tank thoroughly to remove caramelization buildup. In our next article, we’ll talk about why you should thoroughly clean your tank often. Until then, we hope this article has helped shed some light on why your vape juice turns brown. Do you have any stories to tell about how your vape juice turned brown? What about the different methods you use to keep your vape juice from changing colors? Let us know in the comments below! We always love to hear from our fellow vapers. Vaping comes with a steep learning curve, but even the most experienced vapers learn something every day. If you have questions or requests on what our next article should be, email us and let us know what you’d like to read about! Until then, happy vaping and may your tank always be full of delicious flavor!

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