Seen this before? clear VG turns yellowish after mixing

first time this happens to me after a long time mixing so thought to check with you guys here.

i ordered couple of liters of VG & PG few weeks ago - it’s the same brand i always use - noticed all my fresh mixes are coming out yellowish / goldish immediately after mixing - first i suspected it was either the Nic or some of my flavors - then did some testing mixing things separately until i found out that it’s the VG.
the VG is clear in the bottle it came in (water-clear). when i mix the PG with it, it stays clear. only after i mix any flavor or the Nic and stir the mix, it immediately turns yellowish. the mix becomes the same color like a juice that’s been steeped for a month.

yes, i tried to mix the same recipes with a different VG - and the mix always comes out clear (with the same nic, PG and flavors) - so i’m now sure it’s the VG.

the resulting mixes taste fine… no issues. nothing off. no bad smell or bad flavors or anything. so i’m just wondering is this VG bad? should i just throw it away and make new order? if anyone seen this before, or knows why VG does this (chemically), please share thoughts and experiences. thanks

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I would say by your investigation that it is the VG, but it seems odd.

I have heard of VG bing bad before, odor wise. If it came from a reputable dealer like Nicotine River it will have a lot number on it and they will replace it if you contact them.

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I’ve never found VG to be the problem with mixes. It’s all I ever mix with. I would say the nicotine would be the culprit to cause the entire batch to turn

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That’s a new one for me. I have no idea how it could turn color by just agitating it. Bizzare!

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@TheTinMan and @R113 thanks both, i’m 100% sure now it’s the VG. i mixed 0-nic as i was investigating this - got the same goldish color.
i’m guessing the VG is reacting to something in the flavors - water or some other molecules or something - maybe it’s oxidation… but i don’t have the technical (chemical) muscles to know for sure. and as i mentioned, there’s nothing really “bad” with the resulting mixes, just the coloration.

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Sometimes flavors change VG to a yellowish color. Some berry mixes have a tinge of blue on the top. Nicotine causes darkening of the liquid caused by heat air or light exposure. I’m not a scientist and you could be right; although I’ve never experienced darkening of VG on it’s own.

Adding water to the mix doesn’t make it change color. Several flavors do and I’m not exactly sure anymore which ones. Some flavors even make the mixture cloudy…

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That I’ve experienced. Some flavors will tint a mix.

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The latest grape I made has a slight illusion of blue around the outside top edge of the liquid even though it’s clear. Kinda cool

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it’s so strange this thing drove me crazy for couple of weeks - i did exactly the same mix, same ingredients Nic, PG and flavors, so 2 bottles side-by-side, only used this VG in one, and in the other VG bottle from a (older) different order and brand that i still had around - one comes out goldish and the other comes out water-clear.
my only explanation is that this VG got oxidated somehow - maybe it was too hot during transportation or something… and i never seen this before.

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Found this (possibly helpful) information:

One important thing to know about glycerin is that it is susceptible to oxidation into aldehydes and ketones. Once the glycerin decomposition reaches a significant level, the material will turn yellow. This can be delayed by keeping the solution temperature low. Glycerin can be heated at 38-49 °C (100-120 °F) to keep it fluid enough to use, without increasing oxidation severely. In our experience, the grade and source of glycerin makes a big difference in this degradation process. Because it is made from various animal and plant sources, the concentration and type of trace impurities are dependent on the source. Vegetable based glycerin contains less nitrogen, which tends to delay the discoloration onset.

When using a less pure grade of glycerin a yellow discoloration occurs almost immediately (within 24 hours) if the temperature exceeds ~50-55 °C (~122-131 °F). It is worth noting that increasing temperature improves the wettability and dispersion of pigments in glycerin/water mixtures. In using better grades of vegetable-based glycerin no precautions to minimize excess heat have been required. To illustrate this point we subjugated four samples of glycerin to rapid thermal aging until there was a noticeable difference in their color. It took roughly three weeks at 105 °C to produce noticeable yellowing.

Source: https://www.naturalpigments.com/glycerin.html

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It happens. I have taken a steeped “yellow” mix added more flavors and such give it a swirl and it turns pinkish or vise versa. Fresh just mixed mixes can do this with just a swirl too. Every time I add LB Fresh cream
(Which is pinkish by itself) it will react with the nic as soon as I swirl and turns gold instantly. This happens before I add the VG too

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Good stuff! My head got stuck in the VG by itself changing color with nothing added. After I read the second post on testing I realized I was off base. This is happening with other things added. Nonetheless still a valid conclusion by the OP as his only variable was the VG used. Interesting scenario. Heat influence seems unlikely to me but I don’t know how it is being mixed, so I guess possible.

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Perhaps this information may possibly be relevant to your experience (of noting some color changes):

Flavor aldehydes including benzaldehyde, cinnamaldehyde, citral, ethylvanillin, and vanillin rapidly reacted with the e-liquid solvent propylene glycol (PG) after mixing, and upward of 40% of flavor aldehyde content was converted to flavor aldehyde PG acetals.

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Can you share the recipe? I am very curious.

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They shipped you the Quick Steeping VG!!!
Seriously though this seems strange and I have never noticed this happening. You may have hit the nail on the head with your oxidation theory. Will be following along to see if a conclusion is found.

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Apparently heat and or a low grade of VG is the culprit, according to the article posted above. So I wanted to give you the address of the Best VG in the STATES. They have all the specs and how they make it on the web site.

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Yeah, i agree… i think this is the most possible scenario. i think this VG was exposed to heat either in storage or during shipping… thanks @Raven-Knightly and @Dan_the_Man

the logical next question is, isn’t this (oxidation) what would happen anyways when a mix is steeped for few weeks (or months) - so it would be OK to vape, right?

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@Laberythm, i tried different recipes, i initially suspected the cause to be some vanilla or cream-based flavors, that i know may turn a mix into goldish color - but then i tried other “fruit only” recipes, then i tried just PG/VG/NIC, then only a PG/VG mix - and got the same results in all… so it’s not the recipes - and not the discoloration based on flavors.
i think what made me certain that it was the VG, is when i dug out the older VG bottle and managed to do a side-by-side “same mix” comparison just with the different VG.

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they can sell it as “The Magic Pre-steeped VG for an extra kick for all your eliquid mixes” :wink:

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You get that goldish colour by mixing VG only with PG, with not somethink else added? Sorry to asking again but I am afraid maybe I haven’t understand it clear because my English is not good.

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