Secret Key Starting Treatment Essence - Rose Edition
A essence with 17 ingredients.
This hydrating essence is formulated around Galactomyces Ferment Filtrate and Adenosine to hydrate skin and strengthen the skin barrier.
We independently verify ingredients, backed by peer-reviewed research. Suggest an update.
What's inside
Ingredients List
Water
Skin ConditioningGalactomyces Ferment Filtrate
Humectant1,2-Hexanediol
Skin ConditioningRosa Centifolia Flower Water
Skin ConditioningXylitylglucoside
HumectantAnhydroxylitol
HumectantXylitol
HumectantPropanediol
SolventGlucose
HumectantPEG-60 Hydrogenated Castor Oil
EmulsifyingButylene Glycol
HumectantPentylene Glycol
Skin ConditioningAmmonium Acryloyldimethyltaurate/Vp Copolymer
Ethylhexylglycerin
Skin ConditioningAdenosine
Skin ConditioningDisodium EDTA
Parfum
MaskingWater, Galactomyces Ferment Filtrate, 1,2-Hexanediol, Rosa Centifolia Flower Water, Xylitylglucoside, Anhydroxylitol, Xylitol, Propanediol, Glucose, PEG-60 Hydrogenated Castor Oil, Butylene Glycol, Pentylene Glycol, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Ethylhexylglycerin, Adenosine, Disodium EDTA, Parfum
Benefits
Concerns
Ingredients Explained
Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!
Learn more about WaterGalactomyces Ferment Filtrate (GFF) is a byproduct of fermenting Galactomyces yeast (the same yeast traditionally used to brew sake, Japan's beloved rice wine).
Sake brewers have long been known for their remarkably youthful hands. This is what actually first sparked scientific interest in GFF's skin benefits.
GFF works by stimulating filaggrin production in the skin. Filaggrin is a protein that binds structural proteins in the outer skin layer together to form a tight barrier that shields against allergens, bacteria, and moisture loss.
It's also a key building block of our natural moisturizing factors (NMF), or the network of compounds that keep skin plump and hydrated.
By boosting filaggrin, GFF helps strengthen both our barrier and our skin's ability to retain moisture.
Beyond hydration, GFF has notable antioxidant properties that help protect against oxidative stress and UV-induced inflammation.
Research also suggests it may help regulate sebum and keratin production. This could be an interesting option for those concerned about oiliness or skin texture.
Fungal acne:
This ingredient doesn't contain fatty acids or oils that could feed Malassezia, and the yeast used to make it (Galactomyces) is a different genera of fungi from Malassezia. The presence of one doesn't stimulate the other.
However, there is a concern raised by some communities that this ingredient could trigger a reaction in people who are broadly sensitive to yeast/fungal-derived ingredients.
Learn more about Galactomyces Ferment Filtrate1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.
It is a:
- Humectant, drawing moisture into the skin
- Emollient, helping to soften skin
- Solvent, dispersing and stabilizing formulas
- Preservative booster, enhancing the antimicrobial activity of other preservatives
Rosa Centifolia Flower Water is the steam distilled water from the petals of Rosa centifolia, a rose cultivated in France, Bulgaria, and Morocco. It has skin conditioning and soothing properties due to its rich antioxidant content.
Since it's the water-soluble part of distilling rose petals, it's lighter and more dilute than rose extract or essential oil.
Research suggests it can help counteract the enzymes involved in the breakdown of collagen and elastin and have antimicrobial activity against acne-related microorganisms. A comprehensive 2025 review confirmed that Rosa centifolia extracts demonstrate anti-inflammatory, antimicrobial, and antioxidant effects.
Learn more about Rosa Centifolia Flower WaterXylitylglucoside is created from xylitol and glucose, two humectants.
Not surprisingly, this ingredient is also a humectant. It attracts and holds water in your skin, helping to maintain hydration.
This ingredient is most commonly found in a popular trio called Aquaxyl. Aquaxyl is made up of anhydroxylitol(24 - 34%), xylitylglucoside (35 - 50%), and xylitol (5 - 15%).
According to a manufacturer, Aquaxyl is known for a 3-D hydration concept and an anti-dehydration shield to reinforce the outer layer of skin.
Learn more about XylitylglucosideThis ingredient is created from dehydrating xylitol in acidic conditions. Xylitol is a famous sugar and humectant.
Much like its predecessor, anhydroxylitol is a humectant. Humectants attract and hold water to moisturize the skin.
This ingredient is most commonly found in a popular trio called Aquaxyl. Aquaxyl is made up of anhydroxylitol (24 - 34%), xylitylglucoside (35 - 50%), and xylitol (5 - 15%).
According to a manufacturer, Aquaxyl is known for a 3-D hydration concept and an anti-dehydration shield to reinforce the outer layer of skin.
This ingredient is often derived from plants such as wood and sugarcane.
Learn more about AnhydroxylitolXylitol is a humectant and prebiotic. It can help with dry skin.
In studies, xylitol has been shown to improve dry skin. It decreased transepidermal water loss, or when water passes through the skin and evaporates. Xylitol also showed to help improve the biomechanical properties of the skin barrier.
The prebiotic property of xylitol may also help reinforce our skin's natural microbiome. Having a healthy microbiome prevents infection by bad bacteria and helps with hydration.
As a humectant, Xylitol helps draw moisture from both the air and from deeper skin layers. This helps keep skin hydrated.
Xylitol is a sugar alcohol and commonly used as a sugar substitute. It is naturally occurring in plants such as strawberries and pumpkin.
Learn more about XylitolPropanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.
It’s often used to:
Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.
Learn more about PropanediolGlucose is a simple sugar (a monosaccharide). In skincare, it is mostly a humectant and skin conditioning agent.
Mechanistically, it has multiple hydroxyl groups that hydrogen-bond to water. This pulls moisture into the upper layers of skin to keep the surface soft and hydrated.
It's worth knowing sugars are already a natural component of the skin's NMF (natural moisturizing factor) so it's a molecule that your stratum corneum is well-acquainted with.
Just so you know, glucose is hydrophilic (water-loving) and the stratum corneum is a strong barrier to hydrophilic compounds. This just means penetration is slow and most of the action is happening on the surface.
Gram-to-gram, glucose is not as efficient as a humectant as glycerin. This is why you'll likely see glycose paired with stronger humectants for a bigger hydration payoff.
In skincare, glucose is typically derived from corn or other starch sources.
Learn more about GlucosePeg-60 Hydrogenated Castor Oil comes from hydrogenated castor oil. It is a solubilizer and emulsifier.
As a solubilizer, it helps dissolve ingredients into a water-based version. It is also an emulsifer. Emulsifier help prevent oils and water from separating. Both these properties help create evenly-spread and uniform products.
Basically, Peg-60 Hydrogenated Castor Oil helps hold ingredients together.
Learn more about PEG-60 Hydrogenated Castor OilButylene Glycol (or BG) is used within cosmetic products for a few different reasons:
Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
Learn more about Butylene GlycolPentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:
Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.
On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.
Typical use levels in a formula run about 1-5%.
Learn more about Pentylene GlycolAmmonium Acryloyldimethyltaurate/Vp Copolymer is a synthetically created polymer. It's used as a film-forming agent and used to thicken the consistency of products.
Think of it as a supportive ingredient that helps your gel-creams feel silky, "cloud cream-like", and spread evenly without being greasy.
The Cosmetic Ingredient Review (CIR) Expert Panel evaluated it (along with 22 other acryloyldimethyltaurate polymers) and concluded it's:
Due to its large molecular size, it sits on the surface of skin rather than penetrating it.
Learn more about Ammonium Acryloyldimethyltaurate/Vp CopolymerEthylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.
Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
Learn more about EthylhexylglycerinAdenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.
The way it works is fairly well mapped out:
Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down on their own as skin ages, so Adenosine helps give them a little nudge to keep going.
The clinical backing is pretty solid too.
A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at 2 months.
A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.
This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
Learn more about AdenosineDisodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.
This ingredient mainly works behind the scenes and helps with:
On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.
One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).
Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.
You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.
Learn more about Disodium EDTAParfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumReviews
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Where it's from
Secret Key is a Korean brand
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The data we've presented on this page has been verified by a member of the SkinSort Team.
Read more about us· Updated July 29, 2024