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ESPA Optimal Skin ProSerum

Optimal Skin ProSerum

An intensely nourishing serum that strengthens skin’s natural moisture barrier, enhances elasticity to minimise signs of ageing and evens skin tone, for a flawless face. Echium Oil and Sunflower Concentrate replenish, White Lupin smooths and firms, while Turmeric brightens the complexion for beautifully revitalised skin.
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Ingredient name what-it-does irr., com. ID-Rating
Oryza Sativa (Rice) Bran Oil antioxidant, emollient goodie
Helianthus Annuus (Sunflower) Seed Oil emollient 0, 0 goodie
Coconut Alkanes emollient, solvent
Caprylic/Capric Triglyceride emollient
Helianthus Annuus (Sunflower) Seed Oil Unsaponifiables soothing, skin-identical ingredient, emollient goodie
Oenothera Biennis (Evening Primrose) Oil soothing, emollient 2, 3 goodie
Rosa Canina Fruit Oil emollient
Echium Plantagineum Seed Oil solvent
Octyldodecanol emollient, perfuming
Coco-Caprylate/Caprate emollient
Curcuma Longa (Turmeric) Root Extract antioxidant, soothing, skin brightening, perfuming goodie
Ribes Nigrum (Black Currant) Seed Oil emollient
Limonene perfuming, solvent icky
Tocopherol antioxidant 0-3, 0-3 goodie
Cedrus Deodara Wood Oil
Citrus Aurantium Dulcis (Orange) Peel Oil perfuming icky
Cananga Odorata Flower Oil perfuming icky
Crithmum Maritimum Extract
Lupinus Albus Seed Extract
Retinyl Palmitate cell-communicating ingredient 1-3, 1-3
Glyceryl Oleate emollient, emulsifying, perfuming
Citrus Nobilis (Mandarin Orange) Peel Oil perfuming icky
Citrus Reticulata (Tangerine) Peel Oil perfuming icky
Eugenia Caryophyllus (Clove) Flower Extract
Pogostemon Cablin Leaf Extract perfuming
Eugenol perfuming icky
Alaria Esculenta Extract
Spilanthes Acmella Flower Extract
Rosmarinus Officinalis (Rosemary) Leaf Extract antioxidant, soothing, antimicrobial/​antibacterial goodie
Jasminum Sambac (Jasmine) Flower Extract perfuming
Mentha Viridis (Spearmint) Leaf Oil
Plumeria Acutifolia Flower Extract
Rosa Centifolia Flower Oil
Linalool perfuming icky
Ascorbyl Palmitate antioxidant 0, 2 icky
Geraniol perfuming icky
Citric Acid buffering
Cardiospermum Halicacabum Flower/Leaf/Vine Extract
Glyceryl Stearate emollient, emulsifying 0, 1
Lecithin emollient, emulsifying goodie
Benzyl Benzoate solvent, perfuming, antimicrobial/​antibacterial icky
Citronellol perfuming icky
Benzyl Salicylate perfuming icky
Farnesol perfuming icky
Benzyl Alcohol preservative, perfuming, solvent, viscosity controlling

ESPA Optimal Skin ProSerum
Ingredients explained

Also-called: Rice Bran Oil | What-it-does: antioxidant, emollient

The oil coming from the bran of rice. Similar to many other emollient plant oils, it contains several skin-goodies: nourishing and moisturizing fatty acids (oleic acid:  40%, linoleic acid: 30%, linolenic acid:1-2%), antioxidant vitamin E, emollient sterols and potent antioxidant gamma-oryzanol

Also-called: Sunflower Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more  we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.

It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.

What-it-does: emollient, solvent

Coconut Alkanes is a volatile (something that does not absorb into the skin but evaporates from it), naturally derived vegetable alkane coming from renewable sources. It is a light, oily liquid that works as an emollient and gives a smooth skin feel.

It's often combined with another emollient called Coco-Caprylate/Caprate and the two together can serve as a great replacement for some volatile silicones, like Cyclopentasiloxane

What-it-does: emollient

A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular. 

Also-called: Sunflower Oil Unsaponifiables | What-it-does: soothing, skin-identical ingredient, emollient

The unsaponifiable part of sunflower oil. It's the small part of the oil that resists saponification, the chemical reaction that happens during soap making.

If you want to understand saponification more, here is a short explanation (if not, we understand, just skip this paragraph): Oils are mostly made up of triglyceride molecules (a glycerin + three fatty acids attached to it) and during the soap making process a strong base splits the triglyceride molecule up to become a separate glycerin and three soap molecules (sodium salts of fatty acids). The fantastic Labmuffin blog has a handy explanation with great drawings about the soap-making reaction. 

Also-called: Evening Primrose Oil, EPO | What-it-does: soothing, emollient | Irritancy: 2 | Comedogenicity: 3

The oil coming from the seeds of the nice, little, yellow-flowered plant called Evening Primrose. Similar to other plant oils, it's loaded with nourishing and moisturizing fatty acids. It's a very rich source of linoleic acid (66-76%), and also contains the soothing and healing superstar fatty acid, gamma-linolenic acid (aka GLA, 7-12%) (Btw, the richest known source of GLA is the borage oil, but evening primrose still counts as a very good source of it). It also contains oleic acid, but not too much around 6-15%.

Since the 1980's, EPO is a well-known food supplement and there are quite a lot of studies examining what happens if you take it orally. It seems to be helpful with a bunch of  things: atopic dermatitis, dry eyes, brittle nails, sunburn and even acne.

Also-called: Rosehip Oil | What-it-does: emollient

Though it says fruit oil in its name, the rosehip fruit contains the seeds that contain the oil. So this one is the same as Rosa Canina Seed Oil,  or Rosehip Oil, known for its high omega fatty acid content (linoleic acid - 51%, linolenic acid - 19% and oleic acid - 20%) and skin-regenerative properties

There is a common misconception that rosehip oil contains vitamin C as the fruit itself does, but vitamin C is a water-soluble vitamin hence it is not contained in the oil. The antioxidant and regenerative properties of the oil probably come from the oil-soluble tocopherols (vitamin E) and carotenoids (pro-vitamin A). Read more here

What-it-does: solvent

We don't have description for this ingredient yet.

What-it-does: emollient, perfuming

A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.

What-it-does: emollient

A light emollient ester (C8-10 fatty acids connected to C12-18 fatty alcohols) that absorbs quickly and leaves a dry but silky finish on the skin. In terms of skin feel, it is similar to Dicaprylyl Carbonate, another commonly used light emollient. 

Also-called: Turmeric Root Extract | What-it-does: antioxidant, soothing, skin brightening, perfuming

Turmeric is the yellow spice you probably know from curry and Indian food. It's also a traditional herbal medicine used in Ayurveda for its bunch of anti-something magic abilities including being anti-inflammatory, antimicrobial, antioxidant and anticarcinogenic. 

As for turmeric and skincare, we have good news: studies show that the root extract and its main biologically active component, curcumin can do multiple good things for the skin. Thanks to its anti-inflammatory and antimicrobial activity, it shows some promise for acne-prone skin and a small study from 2013 showed that it might be able to regulate sebum production

Also-called: Black Currant Seed Oil | What-it-does: emollient

We don't have description for this ingredient yet.

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

Tocopherol - goodie
Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

We don't have description for this ingredient yet.

Also-called: Sweet Orange Peel Oil, Citrus Sinensis Oil | What-it-does: perfuming

The essential oil coming from the rind of the orange (the sweet one). In general, the main component of citrus peel oils is limonene (83-97% for sweet orange peel), a super common fragrant ingredient that makes everything smell nice (but counts as a frequent skin sensitizer).

Other than that, citrus peel also contains the problematic compound called furanocoumarin that makes them mildly phototoxic. Orange peel contains less of it than some other citruses (like bergamot or lime), but still, be careful with it especially if it is in a product for daytime use.  

Also-called: Ylang Ylang Essential Oil | What-it-does: perfuming

Sweet, exotic and floral, it’ no surprise that Ylang Ylang is a popular essential oil. It is coming from the yellow, fragrant flowers of the Cananga tree native to tropical Asia and, similar to other essential oils, it is a chemically complex mixture with several pros and cons. 

Unfortunately, these are a bit tricky to pin down as the composition varies largely depending on where it is sourced, how the oil is extracted and the grade of it that is used in the product, but we’ll do our best!

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also-called: Form of Retinoids | What-it-does: cell-communicating ingredient | Irritancy: 1-3 | Comedogenicity: 1-3

It's an ester form of vitamin A (retinol + palmitic acid) that belongs to the "retinoid family". The retinoid family is pretty much the royal family of skincare, with the king being the FDA-approved anti-aging ingredient tretinoin. Retinol is also a very famous member of the family, but it's like Prince George, two steps away from the throne. Retinyl palmitate will be then Prince Charlotte (George's little sister), quite far (3 steps) away from the throne. 

By steps, we mean metabolic steps. Tretinoin, aka retinoic acid, is the active ingredient our skin cells can understand and retinyl palmitate (RP) has to be converted by our metabolic machinery to actually do something. The conversion is a 3 step one and looks like this:

What-it-does: emollient, emulsifying, perfuming

The attachment of glycerin and oleic acid that works mainly as a co-emulsifier and stabilizer to create stable water-oil mixes, aka emulsions. It is also popular in cleansing products as it helps to thicken them up and has some refatting and skin-smoothing effect. 

Also-called: Mandarin Orange Oil, Tangor Oil | What-it-does: perfuming

The essential oil coming from the peel of the mandarin orange or tangor. In general, the main component of citrus peel oils is limonene (77-86% for mandarin peel), a super common fragrant ingredient that makes everything smell nice (but counts as a frequent skin sensitizer).  Apart from smelling nice (and thus being a popular natural fragrance alternative), Mandarin Orange Oil also has significant antioxidant properties that's comparable to synthetic antioxidant BHT or oil-soluble antioxidant big shot vitamin E

On the con side, the fragrant components of citrus peels might irritate sensitive skin and citrus peels also contain the problematic compound called furanocoumarin that makes them (mildly) phototoxic. Orange mandarin peel contains less from it than some other citruses (like bergamot or lime), but still, be careful with it especially if it's in a product for daytime use.  

Also-called: Tangerine Essential Oil | What-it-does: perfuming, deodorant

The essential oil coming from the rind of the mandarin orange also called tangerine. In general, the main component of citrus peel oils is limonene (80-97%), a super common fragrant ingredient that makes everything smell nice (but counts as a frequent skin sensitizer).

Other than that, citrus peel also contains the problematic compound called furanocoumarin that makes them mildly phototoxic. In general, the sweeter the citrus, the less it contains, so tangerine peel contains less of it than some other citruses (like bergamot or lime), but still, be careful with it especially if it is in a product for daytime use.  

What-it-does: astringent

We don't have description for this ingredient yet.

What-it-does: perfuming

We don't have description for this ingredient yet.

Eugenol - icky
What-it-does: perfuming

A colorless or yellowish oil that's used as a fragrance. It has a spicy scent and can be found for example in basil, clove or cinnamon oil.

A 2006 in-vitro  (made in the lab not on real people) study examined if clove oil is cytotoxic and found that not only clove oil but also its main constituent, eugenol is cytotoxic even at very low concentration (0.03%). It’s also one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid at least in leave-on products.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also-called: Rosemary Leaf Extract | What-it-does: antioxidant, soothing, antimicrobial/antibacterial

The extract coming from the lovely herb, rosemary. It contains lots of chemicals, including flavonoids, phenolic acids, and diterpenes. Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. 

The leaves contain a small amount of essential oil (1-2%) with fragrant components, so if you are allergic to fragrance, it might be better to avoid it. 

What-it-does: perfuming

We don't have description for this ingredient yet.

What-it-does: astringent

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Linalool - icky
What-it-does: perfuming, deodorant

Linalool is a super common fragrance ingredient. It’s kind of everywhere - both in plants and in cosmetic products. It’s part of 200 natural oils including lavender, ylang-ylang, bergamot, jasmine, geranium and it can be found in 90-95% of prestige perfumes on the market. 

The problem with linalool is, that just like limonene it oxidises on air exposure and becomes allergenic. That’s why a product containing linalool that has been opened for several months is more likely to be allergenic than a fresh one.

Also-called: Form of Vitamin C | What-it-does: antioxidant | Irritancy: 0 | Comedogenicity: 2

A form of skincare superstar, vitamin C. Even though we are massive vitamin C fans,  Ascorbyl Palmitate  (AP) is our least favorite. (Btw, if you do not know what the big deal with vitamin C is then you are missing out. You must go and read our geeky details about it.) 

So, AP is one of the attempts by the cosmetics industry to solve the stability issues with vitamin C while preserving its benefits,  but it seems to fall short on several things.

Geraniol - icky
What-it-does: perfuming

Geraniol is a common fragrance ingredient. It smells like rose and can be found in rose oil or in small quantities in geranium, lemon and many other essential oils. 

Just like other similar fragrance ingredients (like linalool and limonene) geraniol also oxidises on air exposure and becomes allergenic. Best to avoid if you have sensitive skin.

What-it-does: buffering

Citric acid comes from citrus fruits and is an AHA. If these magic three letters don’t tell you anything, click here and read our detailed description on glycolic acid, the most famous AHA. 

So citric acid is an exfoliant, that can - just like other AHAs - gently lift off the dead skin cells of your skin and make it more smooth and fresh. 

We don't have description for this ingredient yet.

What-it-does: emollient, emulsifying | Irritancy: 0 | Comedogenicity: 1

A super common, waxy, white, solid stuff that helps water and oil to mix together, gives body to creams and leaves the skin feeling soft and smooth.

Chemically speaking, it is the attachment of a glycerin molecule to the fatty acid called stearic acid. It can be produced from most vegetable oils (in oils three fatty acid molecules are attached to glycerin instead of just one like here) in a pretty simple, "green" process that is similar to soap making. It's readily biodegradable.

Lecithin - goodie
What-it-does: emollient, emulsifying

A very common ingredient that can be found in all cell membranes. In cosmetics it's quite the multi-tasker: it's an emollient and water-binding ingredient but it's also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes

A common fragrance ingredient that has a faint sweet balsamic smell. It can also be a solvent and can fight against microbes and insects very well.

It's one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. Best to avoid if your skin is sensitive.

What-it-does: perfuming

Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists. 

It can be naturally found in geranium oil (about 30%) or rose oil (about 25%). 

What-it-does: perfuming

It’s a common fragrance ingredient that has a light floral smell.  It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.

Farnesol - icky
What-it-does: perfuming, deodorant

With a sweet, light and floral scent, Farnesol is a popular fragrancing ingredient to make your cosmetics that bit nicer to use. It starts its life as a colorless liquid that can either be synthetically created or extracted from loads of plants like citronella, neroli, ylang-ylang, and tuberose.

The reason we list it as icky is because Farnesol is one of the “EU 26 fragrances” that has to be labeled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential, so it is best avoided if you have super sensitive skin.

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically.

No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. Has to be combined with some other nice preservatives, like potassium sorbate to be broad spectrum enough.  

You may also want to take a look at...

what‑it‑does antioxidant | emollient
Rice Bran Oil - emollient plant oil with nourishing and moisturizing fatty acids (oleic acid:  40%, linoleic acid: 30%, linolenic acid:1-2%), antioxidant vitamin E, emollient sterols and potent antioxidant gamma-oryzanol. 
what‑it‑does emollient
irritancy, com. 0, 0
Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does emollient | solvent
A volatile naturally derived vegetable alkane coming from renewable sources. It works as an emollient that gives smooth skin feel. [more]
what‑it‑does emollient
A very common emollient that makes your skin feel nice and smooth. Comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. [more]
what‑it‑does soothing | skin-identical ingredient | emollient
The small (1.5-2%) part of sunflower oil that resists soap making. It contains valuable skin-nourishing molecules like vitamin E, sterols and fatty acids. It's also claimed to have lipid-replenishing and soothing properties. [more]
what‑it‑does soothing | emollient
irritancy, com. 2, 3
An emollient plant oil loaded with nourishing and moisturizing fatty acids. It's a very rich source of linoleic acid (66-76%), and also contains the soothing and healing superstar fatty acid, gamma-linoleic acid. [more]
what‑it‑does emollient
Though it says fruit oil in its name, the rosehip fruit contains the seeds that contain the oil. So this one is the same as Rosa Canina Seed Oil,  or Rosehip Oil, known for its high omega fatty acid content (linoleic acid - 51%, linolenic acid - 19% and oleic acid - 20%) and skin-regenerative properties.  [more]
what‑it‑does solvent
what‑it‑does emollient | perfuming
A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.
what‑it‑does emollient
A light emollient ester (C8-10 fatty acids connected to C12-18 fatty alcohols) that absorbs quickly and leaves a dry but silky finish on the skin. In terms of skin feel, it is similar to Dicaprylyl Carbonate, another commonly used light emollient.  [more]
what‑it‑does antioxidant | soothing | skin brightening | perfuming
Turmeric Root Extract that has nice anti-inflammatory, antioxidant and skin-brightening properties. [more]
what‑it‑does emollient
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]
what‑it‑does antioxidant
irritancy, com. 0-3, 0-3
Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does perfuming
The essential oil coming from the rind of the orange. Its main component (83-97%) is limonene, the super common fragrant ingredient. [more]
what‑it‑does perfuming
Sweet, exotic and floral, it’ no surprise that Ylang Ylang is a popular essential oil. It is coming from the yellow, fragrant flowers of the Cananga tree native to tropical Asia and, similar to other essential oils, it is a chemically complex mixture with several pros and cons. Unfortunately, these are a bit tricky to pin down as the composition varies largely depending on where it is so [more]
what‑it‑does cell-communicating ingredient
irritancy, com. 1-3, 1-3
An ester form of vitamin A (retinol + palmitic acid) that is pretty much the least effective member of the retinoid family. Its anti-aging effects are quite questionable as well as its behavior in the presence of UVA light. (Use it at night if possible!) [more]
what‑it‑does emollient | emulsifying | perfuming
The attachment of glycerin and oleic acid that works mainly as a co-emulsifier and stabilizer to create stable water-oil mixes, aka emulsions. It is also popular in cleansing products as it helps to thicken them up and has some refatting and skin-smoothing effect.  [more]
what‑it‑does perfuming
The essential oil coming from the peel of the mandarin orange. Contains the fragrant component limonene (77-86%) and makes things smell nice. [more]
what‑it‑does perfuming
The essential oil coming from the rind of the mandarin orange also called tangerine. In general, the main component of citrus peel oils is limonene (80-97%), a super common fragrant ingredient that makes everything smell nice (but counts as a frequent skin sensitizer). Other than that, citrus peel also contains the problematic compound called furanocoumarin tha [more]
what‑it‑does perfuming
what‑it‑does perfuming
A colorless or yellowish oil that's used as a fragrance with a spicy scent. [more]
what‑it‑does antioxidant | soothing | antimicrobial/antibacterial
Rosemary leaf extract - Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. [more]
what‑it‑does perfuming
what‑it‑does perfuming
A super common fragrance ingredient that can be found among others in lavender, ylang-ylang, bergamot or jasmine. The downside of it is that it oxidises on air exposure and might become allergenic. [more]
what‑it‑does antioxidant
irritancy, com. 0, 2
An oil soluble vitamin C derivative that has mixed data about its effectiveness. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like rose and can be found in rose oil. [more]
what‑it‑does buffering
An AHA that comes from citrus fruits. It is usually used as a helper ingredient to adjust the pH of the formula. [more]
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [more]
what‑it‑does emollient | emulsifying
It's quite the multi-tasker: an emollient and water-binding ingredient but also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes.  [more]
what‑it‑does solvent | perfuming | antimicrobial/antibacterial
A common fragrance ingredient that has a faint sweet balsamic smell. It can also be a solvent and can fight against microbes and insects very well. One of the “EU 26 fragrances” that has to be labelled separately because of allergen potential.
what‑it‑does perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming
It’s a common fragrance ingredient that has a light floral smell.  It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” [more]
what‑it‑does perfuming
With a sweet, light and floral scent, Farnesol is a popular fragrancing ingredient to make your cosmetics that bit nicer to use. It starts its life as a colorless liquid that can either be synthetically created or extracted from loads of plants like citronella, neroli, ylang-ylang, and tuberose.The reason we list it as icky is because Farnesol is one of the “ [more]
what‑it‑does preservative | perfuming | solvent | viscosity controlling
It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically. No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. [more]