I found every skincare DIYer & beauty brand’s worst nightmare in the reviews for an $80CAD product on Sephora’s website. This one-star warning was right at the top of the reviews.
I took a look at the other one star reviews, and again—”Horrible. Grew mold”. “Grew mold. Do not recommend.” Oh dear.
But here’s the thing… those reviewers were completely wrong. A few of the reviews complaining about mould included photos; I immediately recognized the problem and quick check of the ingredient list confirmed my diagnosis.
It wasn’t mold, but it was a mistake I’ve seen a lot of DIYers make, too. So, today we’re digging into what that mistake is because you should never have to explain to an upset, grossed out customer or friend that no, that isn’t mold, and even though it is lumpy (sorry about that), it is actually totally safe to use.
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The product in question was a shimmery body oil I found on the Sephora website as I was doing research for a shimmery body oil formulation. It was a completely anhydrous (aka water-free) formulation, so barring some seriously wet contamination, this product literally could not grow mold.
What it was actually doing was going grainy. This problem is much more common in solid anhydrous products like body butters and balms, but certain ingredients and situations can cause it to happen in liquid products, too.
To help you avoid that, let’s quickly recap what graininess is and why it happens.
Oils & butters are made up of a variety of fatty acids like oleic, linoleic, and linolenic (liquid, unsaturated fats) and stearic, myristic, lauric, and palmitic (solid, saturated fats). Each has its own characteristics, but in a discussion of graininess, melting point is the big one.
Graininess happens when a product melts (or even just begins to melt), and then cools the wrong way. The “wrong way” is any way that allows the higher melting point fatty acids in the product to cool before everything else does, creating hard little blobs in a product that’s otherwise softer than it should be.
Because melting is the start of the problem, the closer a product lives to its melting point, the more likely things are to go wrong.
So why was this body oil going grainy? The answer is right in the ingredient list, where coconut oil occupied the top spot.
Coconut oil is a funny “oil”. While oils like sunflower oil and almond oil stay liquid unless you put them in the fridge or freezer, coconut oil will solidify at temperatures below about 24°C (75°F). This means it is usually solid at “room temperature” here in Canada, but will also melt during a summer heat wave.
Coconut oil solidifies for the same reason any solid fat does—it contains a lot of solid saturated fatty acids.
Coconut oil in a tub at “room temperature” in a Canadian summer; it’s started to melt, but is still mostly solid.
According to Modern Cosmetics: Ingredients of Natural Origin, coconut oil is approximately:
- 7% caprylic acid
- 6% capric acid
- 48% lauric acid
- 18% mysristic acid
- 9% palmitic acid
- 3% stearic acid
- 6% oleic acid
- 2% linoleic acid
Lauric, myristic, palmitic, stearic are all saturated, totalling 78% saturated fat content. For comparison, shea butter is only about 42% saturated fat!
If you’ve used both shea butter and coconut oil, you’ll know they’re very different from one another even if they are both solid at 21°C (70°F). Despite its lower saturated fat content, shea butter has a much richer, creamier feel than coconut oil. It also melts much more slowly when massaged into the skin. This is because the primary saturated fats in coconut oil (lauric and myristic acids) have much lower melting points than the fatty acids that make shea butter solid—stearic and palmitic.
Shea butter on the left, coconut oil on the right. They’ve been sitting on my arm for about a minute—notice how the coconut oil is melting quite quickly, and the shea butter is just sitting there? That’s because coconut oil has a lower melting point.
Those lower melting points create a fat that is quite the shapeshifter. If that fat plays the starring oil in a (supposed-to-be-liquid) body oil, when that oil is freshly made and poured, everything is liquid and wonderful—but clearly, it doesn’t always stay that way.
To confirm, I tried it myself. Guided by the ingredient list on the original, I melted together 45% coconut oil, 30% mineral oil, 20% sunflower oil, and 5% bronze mica and poured it into a glass bottle. I then set about trying to mimic what the oil might go through if it was ordered online in at a relatively warm time of year and then lived in a cooler home or apartment.
To approximate what might happen during shipping, I heated it up to about 30°C (86°F)—that’s the oil going from the store to the shipping facility in the summer—and then let it slowly cool back down to room temperature.
I then heated it up again to around 30°C to mimic being out on the trick for delivery. Once the oil “arrived” I let it cool to room temperature and then placed it on a windowsill that was getting down to around 15–17°C (59–63°F) at night and up to 22°C (72°F) or so during the day.
It didn’t take long to find the side of the bottle that was closest to the window lined with solid white lumps. Once the oil warmed back up to room temperature—around 21°C (70°C)—those blobs sunk down, but didn’t vanish.
Gently warming the oil to about 26°C (79°F) did melt the white lumps, but after another night on the windowsill, they were back, and even worse than before. Leaving the oil at room temperature (around 21°C/70°C) for about a week also saw the blobs slowly fade away.
So yes—you can get rid of the lumps but heating the oil or leaving it at a warm-enough temperature for a while. However, if you aren’t a formulator and you’ve spent $80 on a body oil, when you notice highly suspicious white lumps in that body oil, your first instinct is not going to be to microwave it or see if that “mould” goes away after a week. You’re much more likely to take photos, leave a bad review, and throw it out because you think it’s going to give you an infection.
And those suspicious white blobs are just one reason coconut oil makes for a bad ingredient in a body oil! Several reviewers complained that their oil froze solid, making it impossible to use.
Another said “i was really shocked by some of the reviews stating that they couldn’t get the product out of the bottle. For me it was completely opposite. I found it the same texture as pouring oil out of a bottle. I had to give it a good shake to mix it all up. It looked a bit separated.”
I’m betting the customers who struggled with solidification kept their homes cooler than those who described the oil as a thin liquid, while those who experienced graininess kept their homes somewhere in between.
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However this formulation was developed and tested, they obviously didn’t try exposing it to a variety of different ambient temperatures. Frankly, that’s a rookie mistake, and for $80, I expect better (especially since reviews complaining about this go back to 2009!). Even in countries where coconut oil is reliably liquid, someone is going to have their air conditioning set cool enough to cause problems.
As of January 2026, this product is still available for sale on Sephora and the brand’s official website; 2.5oz/74mL is $62USD or $80CAD.
So, lesson learned: don’t use a lots of an oil that easily tips from liquid to solid in a product that’s supposed to be liquid. It’ll solidify and get stuck in the bottle for some customers, while others will be seriously put off by a suspicious (if harmless) chunky mess.
Thankfully, chunky-ness is a pretty easy problem to avoid in shimmery body oils; just stick to liquid oils! The much harder problem to avoid is separation—something else this expensive body oil struggles with. That’s the problem I was working on solving when I found this oil, and you can check out that formulation here. Happy making!
Hey Marie!
Long time no write!
{..What follows is offensively long..}
It’s Suki. Just wanted to second that emotion.
But surprisingly, my example is •not• a lipid.
Whaa??
Ya, if you ever make liniments and pain-relieving embrocations, you may have stumbled across an ingredient oftentimes used for, not just charley-horses, but.. actual.. horses.. {durrrh..
not quite the elegant yet hilarious segue i imagined..}
Uh.. Anyway, ya!
DMSO, aka: dimethylsulfoxide, one might think of it as the product of the deeply despised timber-glutting trade, it’s from the lignins of trees, one •could• even say ‘upcycled’ from trees. Look how natural she is!
The possibly incorrect way i regard lignins is as the ‘mortar’ in the bricks&mortar of cellular infrastructure (as vs. the old ‘b&m’ of our dermal analogies), instead, it might be similar to the fascia giving form around the human skeleton.
Maybe without lignins, a tree would just be a big pile of treebits.
Either way, DMSO is an endlessly fascinating topic to me, chemically. It has some transcutaneous super powers, actually transaLOTTA-ous super powers.
For example, if you are treating a fungal infection in your •nailbed•! You add your antifungal to a specific percentage of DMSO and your antifungal gets special delivery straight to your nailbed {better hope you don’t have a hundred dollar pedicure at the time, though, because DMSO •decimates• nail polish}
Obviously, for an herbal chemistry maniac like myself, how could I •not• fall irrevocably in l❤️ve with this holy substance?
Ok, try to get your uber-verbose a ** back on track, suki!
Point! The point! Is. that. DMSO is frozen solid at up to 20•C|68•F in the literature, though i have seen it rock-solid up to and at 22•C|72•F also, if stored in a gallon jug or larger (because firstly, it really should always be stored in glass, away from light..
{super quick hack: if the price for dark glass is more than for clear, get the clear and use segments of old nylons, and tights etc as cut-to-size ‘sleeves’ to pull over, like a sausage casing, your bottle or jar in order to give it whole or partial opacity to protect your delicate actives}
..to keep it from going ‘garlic-y’, not that this can be avoided persay, but you can try to reduce it.
Also, glass because it can digest many plastics, consider BPA also, and many conventional disposable gloves too! And then, you may as well say ‘hullo, latex solution! Hullo high density polyethylene juice!’
It’s better anyway to store it in smaller than a gallon bottles if possible, because of the already cited reason of avoiding the prolific and dominant fragrance of dur guhrlic (bc opening the bottle and exposing it to air •a lot• assists with the reekification.)
Back to the RT Tundra,
Just as I advised above, I have to pour many little bottles if I ever want to work with it outside of summer, because in smaller fractions, around 8-12 fluid ounces, it •mostly• stays liquid to around 18•C|66•F if my ducks are in a row, my chickens have been sacrificed, and the stars above are in perfect alignment.
And if at the time required, it’s still frozen, well then, it’s considerably easier to warm an 8oz bottle in your armpit or behind a folded knee as opposed to an 8lb gallon jug .
All of this to say:
I just made a ‘neuropathy liquid balm’ for some family members and made my requisite futile attempts to “emulsify” this mixture (of volatile, silicone, earth-based and fixed oils with myriad tinctures, glycerites, solutions containing, among other constituents, piperine or bioperine, Agmatine Sulfate, dimethyl isosorbide, benzyl benzoate, methyl salicylate, menthol, camphor, eugenol, thujone, Magnesium Sulfate and chloride! And of course, the aforementioned DMSO!)
Surprisingly, these ingredients don’t really want to become a uniform substance!
But if I •could• achieve some level of miscibility, it would likely only occur if I first reformulated without the DMSO.
Looking at the above list, stipulating my cold process methodology, is it any wonder that i cannot gain control over the rheology?!
{Although this time at least, I did achieve a thixotropic state from 2% of the old standard, sepigel 305}
Now, in the semi-translucent rollie, it looks downright revolting.
Because of course I had to add a couple drops red 40, so all the bits are everywhere along that spectrum: from whitish to pink, to blood-red, to deepest burgundy, and it hasn’t even had the good grace to separate into distinct layers, instead looking like a tube of bloody squished brains.
Ohh, rereading this really makes me wonder if I should post it ,im such a gabberwocky!..
My husband always says I was born ‘blessed’ with 3x {more like 6x} as many words as everyone else.
Lemme remind you, it’s been way more than a year since I last commented, so i’ve been saving up all my goodies for you, Marie! And bc I post so rarely, you needn’t be subjected to this verbal abuse too often! Right?
{my advice is to send me an email at the address given so we could correspond like grownups in big girl,so i can stop periodically pooping over your comment section,
but do as you will and i will adore you regardless}
As per usual, Marie, you are my guiding light and inspiration.
Muchlove, suki
That’s what I get for using emojis.
Pants.
Big girl pants.
That is all.
Found your page during a search for solubilizers and began pecking around. Enjoyed your article, it was very informative. Thank you!
Also enjoyed reading Suki’s comment. Girl, it’s as if I could hear you speak it 3x (maybe 6x) as fast as most. It was great. Love your energy!
Thanks Michelle!
This is an interesting scenario. There are so many ingredients in products these days, it is tough to be able to trust things as a consumer.
Duuuude, that first commenter was such a d-bag for going on sooo long and so far off topic..
Marie, I apologize for the triatribe {a diatribe is only 2/3rds as long}, there is no good excuse for being so rude.
Rereading your blog post, I just wanted to credit you with once again blowing my mind.
For some reason, (maybe that fatty acids bore the ever-loving sh.. whatever, I just never really •got• the connection between saturated fatty acids and saturated fatty solids!
This completely (finally) penetrated my skull today!
Bc of you and your accessible logic and trustworthy sensibilities, so immediately present in your writing style.
You just saved me time, ingredients and frustration from making crap formulae that couldn’t sustain decent skin-feel nor textural nor visual uniformity! Which are the main things i’ve lately been trying to grasp!
So, i’m sorry and thank you!
You are an absolute genius, especially as a formulator and even moreso, as a teacher!
Now, could you please just explain all the issues with polarity?