We can find three different versions of apple extract for our cosmetic formulating - the powder, the distillate, and the oil. I've found very little about the oil, so we'll concentrate on the powder and the distillate (hydrosol) for now, both of which are water soluble.
Apples and their peels contain a ton of polyphenols - quercetin, epicatechin, procyanidin, chlorogenic acid, coumaric acid, gallic acid, malic acid, catechins - but it's hard to know what's in the extract without specific information from the manufacturers (click here for a great study).
Quercetin is an anti-oxidant, anti-inflammatory, and (possible) anti-viral found in a number of different fruits and vegetables - apples, tea, onion, citrus, tomato, broccoli, cherry, raspberry, cranberry, sea buckthorn, gingko biloba, olive oil, St John's Wort, mango, and grapeseed oil.
Procyanidins are part of the proanthocyanidins group, and occur as esters of gallic acid in green and black tea, grapes, and apples. They are quite unstable, reacting chemically in acid or base solutions, reacting thermally, and oxidizing easily. They are considered to have anti-viral, anti-microbial, and anti-HIV properties, as well as anti-oxidizing through free radical scavenging.
Chlorogenic acid acts as a low level anti-viral and anti-fungal addition to our creations. It offers anti-bacterial properties, which is one of the reasons it is suggested for acne related products. It's a good anti-inflammatory. And, of course, it is a great anti-oxidant.
Catechins are a type of flavonoid, also called condensed tannins. They offer anti-oxidizing features - they have been shown to be more effective than BHT, which is incredibly effective - as well as anti-microbial and anti-fungal properties.
Apples contain Vitamin C, which is a great anti-oxidant, and it behaves as an free radical scavenger, astringent, and exfoliant. A 100 gram apple has about 6 grams, but I'm not sure how much would be found in the powder or the distillate.
It's hard to know how much of anything is in the powdered extract, so I suggest you ask your supplier for their data sheets as we can't get information from manufacturers easily any more. There are some claims that has some salicylic acid like properties for acne, and I've seen claims that it can help with stretch marks. I've been able to confirm that it is an exfoliating ingredient - thanks to the malic acid - which means you don't want to combine it with other exfoliating extracts like papaya or white willow bark - but I can't confirm the anti-stretch mark properties. We can see that any apple extract will be filled with anti-oxidant and free radical scavenging properties and will likely have some anti-inflammatory properties.
I've been using the apple fruit distillate from Lotioncrafters for a while now, and I love the smell of it! It's a steam distilled water that can be used at 5% to 100% in your products (it's preserved, so you can use it in a spritzer for a lovely apple-y fragrance). There are no claims for this specific product, other than the wonderful fragrance of apples. It has a pH of 5.0.
I think this would be a great addition to a facial product for someone with oily skin. Combine it with something like honeysuckle extract at 0.5% and rosemary extract or hydrosol and you've got yourself an anti-oily party going on! (I'll be writing up more recipe ideas for these extracts when I reach the end of the series in about a week! Look for more ideas then!) As with other powdered extracts, you'll want to use apple extract in the cool down phase at 0.5%. I'd suggest dissolving it in a little warm (45˚C to 50˚C) water before adding it to your product.
As a side note, there is a cosmeceutical on the market called PhytoCellTec Malus Domestica, which is an anti-aging product derived from apples. "PhytoCellTec™ Malus Domestica is a liposomal active ingredient based on stem cells from the Uttwiler Spätlauber apple." To learn more, please click here or here. I understand you can buy it at LotionCrafter!
And finally, you can find out more information about the apple seed oil here (a short summary). Sounds interesting.
Join me tomorrow for an aside on malic acid before we take a look at banana extract!