What exactly is lotion?
And how does it compare to cream, body butter, or body whip?
I had a variety of these questions early on, and to my understanding, the definitions aren’t hard and fast.
Very basically, lotion and cream are more or less the same thing*, but lotion is usually thinner and may come in a tube or pump bottle while creams are usually thicker and may be packaged in a jar. Body butter is the least defined—it can be essentially a cream (ie lots of butters mixed with water and packaged in a jar or tub), or an anhydrous (not containing any water) mix of butters and oils whipped together. Body whip is usually a mixture of oils and butters whipped together.
So, we can see theres a bit of a gradient of textures/water contents, and the definitions sort of overlap. Super simplified: lotion is thin, cream is thick, body whip is anhydrous (ie intense and likely greasy feeling), and body butter is somewhere between cream and body whip.
*But what ARE they?!
We know that lotions and creams are similar cosmetics; the key connection is that they’re both emulsions. Think of your favorite vinaigrette: you shake it up to mix it right before pouring it, and if you set it on the table for a few minutes, it quickly separates out into two phases. One phase is aqueous (water-based), and the other is oil. When you mix it up, you’re creating a very unstable emulsion, or mixture of oil-in-water (or water-in-oil depending on your recipe).
The basic principle is that oil and water don’t mix, and so when you physically force them to, they create little droplets of like-minded molecules. Emulsions are everywhere in our daily life: milk, ganache, mayo, toothpaste, bottled shampoo or conditioner, and more.
When we make a lotion or cream (or possibly a body butter), we’re essentially doing the same thing as with the vinaigrette, except that we’re mixing it WAY more intensely, and also stabilizing those droplets with something that will help hold differently-minded molecules together: an emulsifier.
Emulsifiers stabilize an emulsion by making it harder for little droplets to find each other and merge, and eventually separate out into layers. The common thread is that all of them have one end of the molecule that is hydrophilic (water-loving) and one end that is hydrophobic (oil-loving), and so they will coat the little droplets (micelles) and discourage separation of the suspension.
New England Apothecary uses a variety of emulsifiers in our products, including our Magic Hand Cream, Bath Bombs, and Salt Scrub Bars!
In our Magic Hand Cream, we use two different emulsifiers with slightly different properties: emulsifying wax and BTMS-50. Both are doing the same job of holding the oil/butter droplets suspended in water, but the BTMS-50 contains a conditioning agent as well, which changes the skin-feel of my hand cream from a bit waxy to luxuriously silky.
Our bath bombs use a type of emulsifier called a solubilizer (polysorbate-80, aka tween-80 for my labfolk) to help the skin-loving oils actually get into the bath water and onto your skin instead of just floating on the top and leaving a greasy mess.
Similarly, our Salt Scrub Bars use a variety of emulsifiers to help the cocoa butter base rinse off cleanly while still imparting a conditioning feel.
Check back for more detailed posts on why each ingredient was included in our products!
