Newbie Tuesday: Formulating lotion bars

I love lotion bars. They're super easy to make and you can customize them in so many ways! But what is a lotion bar, exactly? These are generally solid-ish, anhydrous products made with oils, butters, and waxes. The basic recipe is generally 1/3 butter, 1/3 oil, 1/3 wax, but you can make loads of modifications to this ratio. (From this post...)

What does this mean? This means that you place your heatproof jug on the scale and measure out 33 grams of your favourite butter, 33 grams of your favourite oil, and 33 grams beeswax. Heat it up until it melts, add up to 1 gram fragrance oil, then put into a mold of some kind and allow to cool until solid. (I like to put it in the fridge or freezer.)

That's it! Seriously? That's it?

Yep. Seriously? I said, yep!

It's amazing how simple it is to make these anhydrous or without water containing products. Whipped butter required two ingredients, and lotion bars require three. But making the product isn't the hard part in most recipes. It's coming up with the skin feel you really want in a product. The fun is experimenting in the workshop with the oils and butters you love! Let's take a look at each component of the lotion bar.

If you want to skip ahead, here's my really detailed post on making lotion bars from the Back to Basics series. This post is more about choosing your ingredients. 

THE BUTTERS
The kind of butter you choose will determine what other ingredients you'll want to use, so this is the logical place to start. If you choose something like cocoa butter, you'll have a harder and less greasy than you would with refined shea butter.

If you came up with a whipped butter-oil combination you loved in your whipped butter, I suggest using those as the base of the lotion bar. I love a mango butter - sunflower or soy bean - rice bran oil combination for my slightly oily skin when I'm using them as a foot or chapped skin bar, but I really like mango butter with lanolin, lecithin, hazelnut or soy bean oil for my cuticle balm.

The colour will also depend upon the type of butter you choose. I can make my all white lotion bar using mango butter and white beeswax or the slightly beige kokum butter bar, all coloured by the butter. (Click here for a post on other butters...)

THE WAXES
How much wax you'll use will depend upon the type of butter you chose. Cocoa butter is a harder butter, so you'll use less beeswax (as low as 25%). Mango butter is in the middle, so you can use 28% to 33%. Shea butter will vary, but I generally use 33% with my refined and ultra refined shea butter because it's so soft. The goal is to keep the bar solid when it is in the container or your hand, but to have it melt when it hits your skin. The beeswax will increase the melting point and drag on your skin, so you don't want to use more than you need.

There are other waxes you can choose - click here for a list - and you'll have to play around with them to see what works with your oil and butter combination. In general, carnauba and candellia require about half the amount you'd use for beeswax and soy wax will require a little more than beeswax. It really is something you have to try in the workshop.

THE OILS
Choose an oil that goes with your skin feel. Again, if you found a combination you love for the whipped butter, go with that and add the beeswax to it in the right proportions.

Because your oil amount is larger, you can play with oil combinations. Try 10% of one thing and 23% of another or 16% and 17% or 10%, 10%, and 13%! Spend a bit of time reading up about your emollients if you want to get creative.

A FEW LOTION BAR RECIPE IDEAS
As usual, feel free to alter pretty much anything in the recipe to match what you have in your workshop.

BASIC RECIPE
33% beeswax
33% butter of choice
33% oils of choice
1% fragrance or essential oil

REFINED SHEA BUTTER LOTION BAR
33% beeswax
33% refined or ultra refined shea butter
33% oils
1% fragrance oil

Consider non-oils like cyclomethicone (2%, cool down), dimethicone (2%, cool down), IPM (up to 5% in the heated part), and so on. Cyclomethicone makes the bar feel drier and adds some silkiness to it. Dimethicone will offer some barrier protection and a glidy feeling. And IPM helps reduce the feeling of greasiness that might come from the oils.

MANGO BUTTER LOTION BAR
28% beeswax
30% mango butter
31% oils (16% sunflower oil, 15% rice bran oil)
5% IPM

COOL DOWN PHASE
1% Vitamin E
1% fragrance or essential oil
2% cyclomethicone
2% dimethicone

Can you predict what this lotion bar might feel like? 

LOTION BAR FOR CUTICLE CARE WITH LANOLIN AND LECITHIN (from this post)
28% beeswax
30% mango butter
10% lanolin
10% lecithin
20% oils of choice - hazelnut or soy bean are good choices
1% Vitamin E (optional)
1% fragrance or essential oil

Melt everything except the Vitamin E and fragrance or essential oil in a heat proof container in a double boiler. When the ingredients have melted, remove from the heat and add the Vitamin E and fragrance oil. Pour into mold or container and let set. Rejoice.

MAKING THE RECIPE
I don't recommend you make more than 100 grams the first time you make lotion bars for two main reasons. (In fact, may I suggest trying 50 gram batches?) One, you are experimenting, and you don't want to make a ton of them so you have a cheap excuse to play further. And two, 100 grams makes a lot of lotion bars.

If you're putting them in lip balm containers, consider that the ones I bought from Voyageur hold 4.5 ml, a little less than a teaspoon, so 100 grams is going to make more than 20! If you're putting them in these little deodorant containers, consider you can make something like 10 of them with 100 grams. If you're putting them in little tins, consider that the the little chocolate molds held about 12 grams, so you can make 8 of them! I love lotion bars, but I can make them last a really long time!

THE MOLDS
There are many ways to store your lotion bars. Lip balm tubes, deodorant tubes, little tins...or you could go with plastic chocolate molds, silicone ice cube trays, soap molds, massage bar molds, and so on. Just have something you can put the non-containered lotion bars into when you're done. I like little tins or cellophane bags.

You can make quite large lotion bars - think of massage bars, for instance - but I really do suggest you start small and work your way up in size once you find a recipe you really like.

ONE FINAL NOTE...
I regularly say you can use 1% fragrance or essential oil to fragrance your products...be careful with essential oils, and read up on them before using in your products. Some have lower than 1% suggested usage rates, some aren't suitable for leaving on the skin (citrus might make you photosensitive, for instance), some aren't suitable for some applications (peppermint might not be the best choice for a bath bomb), and some aren't suitable for some conditions, such as pregnancy.

Well, what are you waiting for? Get into the workshop and make some lotion bars! And post your results here so we can talk about it next week! (As usual, posts will be eligible for a random draw for your choice of an e-book!)

I've created a visual tutorial on SnapGuide to help you make lotion bars! 

Posts on lotion bars:
Back to basics: The basic recipe
Back to basics: Lotion bars - tweaking the waxes
Back to basics: Lotion bars - tweaking the butters and oils
Back to basics: Lotion bars - let's get complicated
Back to basics: Lotion bars - wrap up and link-o-rama
The chemistry of our nails: Lotion bar with lecithin and lanolin

Want to join in the fun? Check out the previous posts in the Newbie Tuesday series!
Newbie Tuesday: Learning about oils and butters - an introduction
Newbie Tuesday: Testing the skin feel of our oils
Newbie Tuesday: We're pushing the schedule back a week (great discussion here about the skin feel of our oils!)
Newbie Tuesday: What did you learn about the skin feel of your oils?
Newbie Tuesday: Creating a body oil
Newbie Tuesday: Creating whipped butters - choosing your butters
Newbie Tuesday: Creating whipped butters - recipes to try
Newbie Tuesday: What did you think about your whipped butters?
Creating whipped butters: A visual tutorial (Snapguide)

Join me next week when we take a look at your questions, comments, and recipes for awesome lotion bars! 

My visual guide to creating lotions!

I've just completed my visual tutorial on making a basic lotion at SnapGuide! I've based the guide on this Newbie Tuesday post on making a lotion for the first time, and you can download the accompanying PDF as it goes into more detail than the guide (but as much detail as the original post). If you're a complete newbie, I hope this helps you dive in and try it for the first time. If you've made them before, I hope it helps you see where you're doing it right!

In one of the steps, I posted the video of the moment of emulsification. If you've never experienced it, take a peek! I hope you enjoy it! 

(Long) Weekend Wonderings: Altering the pH of our products, freezing fragrance oils, and using butylene glycol as a co-preservative

ALTERING THE pH OF OUR PRODUCTS
In the Weekend Wonderings comment post, Liz asks: First off I have to say your blog is so informative- you are my bath and body hero! And I have a question for you, with summer coming up I wanted to make a sunless tanning lotion. I bought some Dihydroxyacetone and Erythrulose from Making Cosmetics. It says not to use alpha-hydroxy acids with the dihydroxyacetone but the "final product should be in the pH range between 3.5 and 5". I'm trying to figure out what to use to lower the ph. White vinegar? I don't really want to smell like that if possible. Thanks so much with sharing your knowledge so freely with us!

The first thing I suggest is to make sure you have a good way of measuring pH in our products. I'm not a fan of using pH strips as they aren't really that accurate, so if you plan to make products of this nature, you might want to invest in a pH meter. I love my meter, but there are many of them to choose from from our lovely suppliers, and I'm sure you'll find one that you can afford and love.

So how to lower the pH of our products? I don't think I'd want to use vinegar because it's not predictable how much acetic acid it contains - every type of vinegar is different - plus there's a smell involved! Citric acid is a very effective way to reduce pH - I've found that 0.2% in my body washes can reduce the pH up to 1 point, making it more acidic. Lactic acid is another way to reduce it, although I have no suggestions for usage.

Click here to see how I use citric acid
Click here to see how I used it in a body wash!

Having said all of this, some people love their strips, so perhaps they'll comment and let us know how they make them work well for them! And any suggestions for reducing pH that don't include AHAs? 

Related posts: 

pH and bath products

Chemistry: Adjusting the pH of our products

Chemistry of our skin: pH and the acid mantle (scroll to the middle for pH adjusting)

Chemistry of our skin: An updated overview (updated for 2012)

Chemistry of our skin: pH of our skin (updated for 2012)

Chemistry of our skin: pH and our skin care products (updated for 2012)

I'll be writing more about pH in a few weeks as I resume the Chemistry Thursday series! There are so many misconceptions about acids, bases, and pH that I thought it would make for an interesting series of posts!

CAN WE FREEZE FRAGRANCE OILS?
In the same post, Yvonne writes: I have a question about fragrance oils. I have so many of them which I don't use up before the year is up as I only make products for myself (the supplier told me they are only good for 1 year). Could I freeze them like I do my carrier oils?

Yes.

Related post: Heating, holding, freezing, and thawing our ingredients

CAN BUTYLENE GLYCOL BE USED AS A PRESERVATIVE?
In this post, melian asks: I have a question for weekend wonderings. On the Dish (forum) at one time the statement was made: "Butylene glycol may act as an additional preservative in your lotions." Though I keep it in my notes, I didn't keep track of who said it, so I can't go back to them. Is this true? I've already done a search on the blog and read everything about butylene glycol.

I'm not sure about butylene glycol, but I know that glycerin can be considered self preserving by the FDA, "Some cosmetics, i.e., those containing more than about 10% ethanol, propylene glycol, glycerol, etc., and cosmetics in self-pressurized containers, are self-preserving and are not likely to become contaminated with microorganisms." (Original post: Can glycerin act as a preservative?)

I've also seen 15% to 20% suggested (Dweck) or 50% suggested in this discussion thread in the Chemist's Corner forum. I could post references all day, but suffice it to say that a certain amount of glycerin can behave as a preservative for our products.

How would this work? In a product, the water is bound to other molecules (say, Epsom salts) and isn't free for usage by the microbes. In other cases, the water is bound by humectants like sorbitol or glycerin (anywhere from 10% to 20% will bind water). So water activity is actually a measure of the amount of free (unbound or active) water molecules present in our products. Water activity increases or decreases with with increases or decreases in pressure and temperature. pH also plays a role.

So why am I talking about glycerin instead of butylene glycol? Because they are all poly-alcohols or polyols, and these ingredients bind to water molecules in the product, which is how they could work as preservatives.

Having said this, I wouldn't trust these polyols as the only preservative in a product because figuring out the water activity isn't as simple as adding 10% or 20% of something to a product - click here to see the equations and information. Besides, who wants 10% to 50% humectant in a product? It would feel really sticky on your skin. (I do have a 25% glycerin foot cream I make when my feet are really trashed, but I need to wear socks and I'm covered in fluff in the morning!) I think using them can offer a boost in preservation (and it reduces the freezing point of your product, which is great if you're shipping your product in the winter or storing it on your workshop in colder months).

Have a question? Hie thyself over to the Weekend Wonderings comment post and share your thoughts. I go through all the comments you make every week on this blog, but I check there first! 

Weekend Wonderings: Cetyl alcohol really isn't an emulsifier, making a Vitamin E product, and non-smooth looking lotions

I mentioned in this post on Friday that cetyl alcohol isn't an emulsifier. I want to mention it again. It really isn't an emulsifier. It will not bring together water and oil. It is an oil, so if you mix it with a water soluble ingredient or into a water soluble product, it will eventually float on the top of your product in an icky mess.

If you want to add an oil to water or a water soluble product, you need to add an emulsifier. If you want to add cetyl alcohol to a water soluble product - for instance, if you want to make a conditioner with cetyl alcohol as the only oil soluble ingredient - you need to add an emulsifier. Cetyl alcohol has no characteristics that make an emulsifier or allow it to emulsify with water, so if you melt it and add it to water, it will not mix. (If you're curious why oils float on top of water, read this post on specific gravity!) I'm not trying to be a downer by telling you what you can't do: Im trying to help you make awesome products! 

In the Weekend Wonderings's comment post, Simone asks: My question is: Can I make a petroleum gel style of ointment that would deliver the Vitamin E but not melt into my eye? 

She also asks: I must have missed your post 26th April which includes an anhydrous eye shadow primer. Do you think I could use this base for the Vitamin E cream that I need to use for the scar on my eyelid? If I substitute Vitamin E for the some of the oils. I appreciate your opinion and realise it is just that, an opinion, but you have so much more experience than many of us who read your blog.
The doctor said nothing oily which kind of narrows it down. I still have to research your blog for the Cera Belina.

Hi Simone. I'm really uncomfortable suggesting something to put near your eye, so I'm just making comments on what you've written and ask that you don't do anything I've written here without speaking to your physician. Did the doctor mean "nothing oily" to mean you can't use anything with oil in it or did the doctor mean you couldn't use anything that was thin like an oil? I ask because Vitamin E is oil soluble, so by definition, Vitamin E is oily.

As for making a petroleum style ointment, you could make something like that. A common one we see is about 8% beeswax and 92% castor oil (or another heavy oil). Heat up these ingredients until melted, then whip! (Adding air gets the jelly like texture!) Add up to 1% Vitamin E in the cool down phase. As for using the primer recipe, sure. It's just a lip balm recipe with zinc oxide added. I don't know if the zinc oxide will do anything for you, so feel free to remove it and add up to 1% Vitamin E at the cool down part.

Again, in that post Rosi asks, My comment is although we can add as much and whatever we want in our lotion I haven't got a lotion that looks as uniform and smooth as the ones commercially made. I've been making leave in conditioner for a year and it always have very tiny particles that looks like it has not been mixed/blended in together, whether add more or less emulsifier it does not have a nice consistency. Is it always like that, does it happen with anybody else? I use BTMS 25, one oil, Cetac, cetearyl, water and preservative.

Hi Rosi. We really can't add what we want to a lotion as there are ingredients that make our products less stable - for instance, more oil than the emulsifier can handle or large amounts of green tea extract (more on this soon!) - but we can develop recipes to include those things we want. Your lotions, conditioners, leave in conditioners, and other emulsified products should look as smooth and consistent as a commercial products! 

It sounds to me like you are experiencing a lotion fail. A conditioner is a type of lotion - it contains water, an emulsifier, a preservative, and an oil phase - so it follows the same rules as a lotion. I fear your BTMS-25 might not be enough to emulsify your product - it isn't a great emulsifier compared to BTMS-50 - or your oil phase is too large (oil plus cetearyl alcohol). Cetrimonium chloride can cause some separation of ingredients, something I've noticed doesn't happen as much if I put it into the heated water phase, which seems counter intuitive, I know! 

Can you post your recipe so we can take a look at it?

There are a few things we can do to avoid a lotion fail. As I mentioned above, make sure you're using enough emulsifier for the oil phase. Make sure what you are using is an emulsifier. Make sure you're following the basic lotion making instructions, heating and holding both phases at 70C for 20 minutes. Mix well. 

We'll revisit this topic when we see Rosi's recipe! 

Join me tomorrow for the long weekend edition of Wonderings! 

If you aren't curious...

I have to confess I'm surprised at the lack of curiosity from some of the readers of this site. I link constantly in the posts I write, and I can't believe how many comments or e-mail messages I see asking me questions that could have been answered by clicking on one of those links. (I'm thinking about the ingredient cetyl alcohol from Friday's post.)

You don't have to know everything to make a great product, but it's fun when you do! You can make a gorgeous whipped butter or lotion following someone else's recipe, but you're beholden to those ingredients and that process if you don't spend a little time reading and learning. You'll be unable to figure out what makes a good recipe, which leaves you making products that suck and wasting your precious supplies. You'll be unable to fix a lotion fail and you'll end up spending a ton of money on the same ingredient at different suppliers' shops if you don't know INCI names.

Follow your curiosity and see where it leads! Follow that link to the next one, then the next one, then the next one, and read until you see the same information repeated a few times. Get into the workshop and that try that thing that sounded interesting when you thought of it in the shower, then figure out why it worked or didn't work. (Like my solid body wash idea!) Get into the workshop and get a feel for your ingredients (like we did with oils in the Newbie Tuesday series on the skin feel of oils and butters).


If you aren't curious, I really don't think you should consider creating a business making bath & body products. To become a proper artisan, you need knowledge, and the only way to get that knowledge is through hard work and curiosity. (How do you know you have the interest and the aptitude to create products if you don't learn all you can?) You should be able to write recipes and predict the viscosity and skin feel of the product before you consider selling, and you should be able to make substitutions on the fly when you run out of ingredients. 

If you really want to make products, make yourself a promise that you'll be curious for an hour this week and learn more about one ingredient. Check out the emollients (oils, butters & esters) section and learn about one oil or butter this week, check out the extracts section to learn about your favourite botanical ingredient or hydrosol, or look to the bath & body guides to ingredients on the right hand side of the blog and find an ingredient you love! I know we're all pressed for time, but I can guarantee you can find 9 minutes a day to read something interesting on this blog or others you frequent! And by the end of the year, you'll have learned about thirty (or more) ingredients for such a small investment every day!

What are you curious about and where will you start?

Quick note for a long weekend Friday: Cetyl alcohol is not an emulsifier

Quite a few times in the last week I've seen cetyl alcohol referenced as an emulsifier, something that will bring oil and water together. It is not. It's an oil soluble fatty alcohol that should be treated like you would an oil or anything oil soluble, which is to say you can use it in an anhydrous product - like a lotion bar or whipped butter - but you can't use it in anything water based - like a body wash or toner. You cannot use it to create a lotion - you will need an emulsifier for that purpose - but you can use it as a lovely emollient in a lotion. 

Click here to learn more about emulsification! 

Click here for more about all-in-one emulsifiers. 

An emulsifier or surfactant has to have a hydrophilic (water loving) or polar head and a lipophilic (fat loving) or non-polar tail. One end connects with water, the other with oil, and it brings the two things together. Cetyl alcohol, cetearyl alcohol, behenyl alcohol, stearic acid, beeswax, and other waxes only have lipophilic or oil loving parts. They cannot be used as an emulsifier because they lack the hydrophilic or water loving parts, which means they won't bring water and oil together. 

Cetyl alcohol might not be an emulsifier, but it's a great thickener for our products.  I like to use cetyl alcohol in my lotions to increase the viscosity and increase slip and glide. Stearic acid will increase the viscosity, but it offers a little more drag and thickness than cetyl alcohol. It's inexpensive - I think I pay about $4 a pound for it (about $8 a kilogram) - and it works well to moisturize without oils. I like to use it in my facial moisturizers to offer oil free moisturizing to my acne prone skin, and it's a lovely addition to a lotion bar to make it glide a little better. 

If cetearyl alcohol interests you, take a look at this recipe for turning an oil into a whipped butter. 

Back to the very basics: Conditioner

I think conditioner might be the most popular topic on this site, so let's take a few moments to learn more about it!

Hair conditioner: A hair conditioner is a positively charged or cationic product. Your hair is negatively charged, and for something to be a hair conditioner, it must be positively charged to adsorb to the hair strand. No positive charge, no adsorption, no conditioner. It can be a liquid or a solid (bar form). It can be thin enough for a bottle or thick enough for a jar. The key thing that makes it a conditioner is the cationic or positively charged emulsifier - something like Incroquat BTMS-50, Incroquat BTMS-25, Ritamulse BTMS-225, or cetrimonium bromide, to name a few ingredients you can buy.

Click here to get a full post on how conditioners work. Adsorption means the molecules accumulate on the surface of your hair. It's different from absorption in that it doesn't penetrate, it just sits on top of the hair fibre.) This is called substantivity. 

If you are looking to buy an emulsifying conditioner or a conditioning emulsifier or some variation on these names, read this post on reading INCI names so you buy the right thing! You are looking for something like behentrimonium methosulfate in list of what's in the product. You can get BTMS-25, which has 25% behentrimonium methosulfate, or BTMS-50, which has 50% behentrimonium methosulfate. I use the 50% in all my produts. If you've bought BTMS-25, click here for a post on how to adapt recipes to use it properly. (And click here to see the difference in using the two products on your hair!) Those white pellets in the jug are Incroquat BTMS-50, and most emulsfiying conditioning thingies will look like that. The yellow pellets are Incroquat CR, which I use to add softness, anti-static, and detangling properties to my conditioner bars.

Incroquat BTMS-50 and other cationic quaternary compounds are emulsifiers, which is how you can melt it and add it to water and have it remain emulsified! It also means that you can add oils, silicones, butters, and other oil soluble ingredients to your conditioner and know that it will remain emulsified!

Rinse off conditioner: This is a conditioner you rinse out of your hair after washing. It can have any level of cationic ingredients it wants!

Leave in conditioner: This is a conditioner you leave in your hair after washing. These tend to have 1% to 3% cationic ingredients and a lot of things to help with styling or drying, like silicones or moisturizers. You might find it in a normal or spray bottle.

Intense hair conditioner: This doesn't have a real definition, but generally we use it to mean something that will moisturize or condition our hair really really well and leave it more conditioned than normal. It could mean that. Or it could mean the smell is intense, the container is intense, or anything else is intense. I use it to mean something to which I've added more than 7% BTMS-50 or Ritamulse BTMS-225, but that's only my definition. Everyone's definition will be different.

Click here for information on how the recipes for these products differ! 

How long do you think you should leave conditioner on your hair for maximum results? Have a guess! The answer's at the end of the post.

You can make a lovely coconut oil and mango butter hair thingie, but it's not a conditioner if it isn't positively charged. Every day I see people calling things conditioners are clearly aren't. This isn't a matter of semantics or me being picky. Just like a lotion is by definition an emulsified product - no emulsification, not a lotion - a conditioner is a positively charged product that adsorbs to the hair strand. No adsorption, no conditioner. Coconut oil moisturizes your hair beautifully, but it doesn't adsorb to your hair strand, so it isn't a conditioner. Apple cider vinegar does something to your hair - I can't find anything describing what it does, other than "making the cuticle lie flat" - but it doesn't adsorb to the hair strand, so it isn't a conditioner. If you want to know more about conditioners, visit the hair care section of the blog and look at the posts on the topic. There are so many recipes there, you'll have to take a look and see what you like.

Answer? About 2 minutes. That's right! There's no reason to condition overnight, unless you want the benefits of the oils or other ingredients you've included in your product!

Troubleshooting a lotion recipe...

In this post on making a basic lotion, Courty asks: I tried your summer lotion the other day. (Was it this one?) I love it but have a problem I was hoping you could help with. It rubs in very well when my skin is dry but if I apply it after I get out of the shower it drags and skips and doesn't rub in smoothly at all! Do you know why this happens and if I can fix it? I used what I had so I simplified a lot when substituting your recipe.

Here's my formula:
71% Water
3% Vegetable Glycerin
20% Organic Olive Oil
3.6% Glyceryl Stearate
1.4% Cetyl Alcohol
.5% Potassium Sorbate
.5% Vit E

Quick aside: Please always include your process when writing to ask me for help. It makes it so much easier to figure out what you did.

It sounds like the emulsion is breaking when you apply it to your skin. I think the problem is that your lotion isn't properly emulsified. You aren't using an all-in-one or combination emulsifier and you don't have a complete HLB emulsifier. Glyceryl stearate is a low HLB emulsifier (HLB 3.8) that needs to be paired with a high HLB emulsifier to create a complete emulsifier. Cetyl alcohol isn't an emulsifier - it's an emollient like our oils and butters - so you have an incomplete emulsifier in the form of glyceryl stearate. You could include any of the higher HLB emulsifiers to make this work, but you'll need to work on the math again!

So why is this happening only after a shower? It could be you're adding just enough water to mess with the product or it could be coincidence. Either way, the lotion is unstable and the emulsion will break sooner rather than later.

Why has it remained stable for a while? Emulsification relies upon three things - heat, mixing, and chemistry. The chemistry part is the all-in-one emulsifier. The heat is the heating and holding part. And the mixing is the mixing part of the process. You can get an emulsification using only one of these three things - look at shaking a salad dressing - but it will fail in a really short period of time, like hours. You can get an emulsification using heat and mixing - look at using beeswax (not an emulsifier) in a lotion - but again, it will fail. Using all three ensures we get a nice, stable emulsion that won't fail for a while. (All emulsions will fail eventually, but when we use all three methods, we could see it last for years, well beyond the time it is good!)

Related posts:
Emulsifiers: Questions about VE and MF emulsifiers
Emulsifiers: Check what you've got! 
HLB system (PDF from Lotioncrafter)
When lotions go wrong! 

As a secondary note, you aren't using a broad spectrum or complete preservative in this product. Vitamin E is an anti-oxidant, not a preservative, which is to say that it helps retard the rancidity of our oils, butters, and other ingredients with fatty acids, but it doesn't keep contamination away. Potassium sorbate is good with yeast and fungi, but isn't good with bacteria, which means you're leaving yourself open to some serious beastie growth! (What contaminants can get into our products?) I suggest finding a broad spectrum preservative that offers protection against all possible contaminants!

Let us know how the next batch turns out!