I write this post about how I'm back, then I forget to hit publish on yesterday's post! I guess I need more vacation time!
white willow bark, salicylic acid, or papaya, for instance.
The main attraction in pineapple extract is bromelain, which is (to quote the University of Maryland website) "a mixture of protein-digesting (proteolytic) enzymes found in pineapples". This mixture has been shown to be good at debriding (removing dead skin) from third degree burns and can be used topically to reduce swelling from insect stings and bites (which I really need right now, stupid mosquitoes). Like the papain in papaya, bromelain can be used as an exfoliant in cosmetic products, which is why I suggest not using it with another exfoliant. It has some anti-bacterial benefits
In theory, bromelain would work reduce the adhesion between the dead skin cells on the surface of our skin and encourage them to slough off to reveal nice new skin cells, much like salicylic acid does. (Click here to learn more about desquamation!) Unfortunately, there has been very little study on how bromelain works with our skin (source) and the third degree burns study above appears to have used 35% bromelain as opposed to the 0.5% pineapple extract that we'd use in our products. There is no guarantee that there is enough bromelain in 0.5% pineapple extract to encourage desquamation.
Bromelain is used as a meat tenderizer because it breaks down proteins, and we can find it in a powdered form in grocery stores for this purpose. I was reading about a company that is using bromelain in their products as it "hydrolyses proteins into peptides and amino acids" (link to press release), although I'm not really sure why this would be a good thing in a product because our proteins are already hydrolyzed (like Cromoist) and I can get peptides and amino acids to put into my products. I guess I'm thinking more like a formulator and less like a consumer here, eh?
There are many reasons to take bromelain internally as it may be good at reducing pain, swelling, and water retention, but this isn't a blog about taking supplements, so we'll leave that topic alone. And there's some evidence that bromelain might be able to remove protein stains from laundry.
My mom's best friend used to put meat tenderizer on our bug bites and stings as a kid. I thought it was odd, but I trusted her because she was a nice adult. I guess she was right!
There are other benefits to pineapple extract such as anti-oxidants that will retard rancidity in our products, anti-inflammatory properties to reduce redness, swelling, and inflammation, and possible anti-bacterial properties (but not enough to make it a preservative!). Pineapple extract can cause irritation to those with sensitive skin, so be wary before adding it to every facial product you own (in fact, if you want to use it, try it in one product - like a facial cleanser - before adding it to each product individually to avoid extreme exfoliation).
If you want to make a coconut oil and pineapple extract product and call it a pina colada lotion, have at it, but I don't think there's enough information yet that the amount of bromelain found in pineapple extract will benefit our skin.
When you're using fruit extracts - and, indeed, most extracts - you'll be adding them to the cool down phase at around 0.5%. For something like a shampoo, lotion, or other thick product, I like to pour a little heated water at 45˚C to 50˚C (the temperature of our cool down phase) - not much, maybe 5 to 10 ml - into the powdered extract and mix until it dissolves. Then I add it to the product and mix well. If I'm adding it to something like a mister or toner - something that's pretty much all water - I don't bother dissolving it!
Join me tomorrow more fun with why did I buy that ingredients!