Saturday, February 9, 2013

Weekend wonderings: Rice bran oil, stearic acid, shampoo bars, and using glycerin in anhydrous products

Every day I see so many great comments and e-mail messages from wonderful readers like you, but I find I have a hard time getting to them when I only have so much time to write in the mornings. So I've decided to create a new series called Weekend Wonderings where you can find those great comments and questions! Here's the first one...Let me know what you think!

In this post, Michele asks: Oh, I just made a lotion with rice bran for the first time last week. I like it. What are the chances of it staining clothes/sheets at 3%?

I use a lot of rice bran oil - it's one of my favourite oils - and I've never had it stain my clothes or other fabrics! I use it in large quantities, too. I might use it at up to 20% in my lotions, and I've used it at 75% in these Lipidthix experiments. I haven't had a problem with stains of any sort using these products!

Aditi asks in this post on stearic acidInteresting......I was searching for an answer to reduce oilyness in my creams. Do we first dissolve stearic acid in water and then mix it with oil?

Hi Aditi! Stearic acid is oil soluble, which means you can't dissolve it in water. You would include it in your heated oil phase with your other oil soluble ingredients, and it would melt in that phase.

Stearic acid won't reduce the feeling of greasiness in your products. Its purpose is to make our products thicker and offer emolliency. If you want to make your product less oily, I've put together a little reading list below about creating drier feeling lotions. The easiest ways to create a drier or less greasy feeling lotion include choosing your oils carefully - using hazelnut or macadamia nut oil - or choosing your butters carefully - mango instead of shea - or adding esters - up to 5% IPM or IPP in the heated oil phase.

Related posts:
Men's products: Formulating a drier feeling lotion 
Men's products: Formulating a drier feeling light lotion
Men's products: Formulating a drier feeling lotion with esters

In an e-mail, Gabrielle asked: I've been reading about shampoo bars and saw your shampoo bar overview post, but have a question about it. Was wondering why your recipes for shampoo bars call for powdered and liquid surfactants? Is there a reason why they must be made with a combination of both? If so, are you able to advise why, please?

I've never been asked this before...but it's a great question! The answer is pretty simple - if you use all powdered surfactants, the product would fall apart. And we use liquid surfactants to give us other qualities we can't find in the powdered ones. For instance, SCI has a lovely foam and elegant skin feel, but C14-16 olefin sulfonate is great for oily hair, SMC taurate is good for dry skin, cocamidopropyl betaine is fantastic for increasing mildness, and so on.

Bob writes in this postHi Susan- I totally love your blog! I just found it while looking for info on Allantoin after discovering it wasn't soluble in either oil or water. : ( I make creams that are entirely fat based (shea butter, coconut oil and olive oil), infused with herbs and with essential oils added. I like the fact that they are 100% organic and that I can grow some of the herbs. Here is my question and I'm sorry if it is off-topic to the conditioner post!- How can I put say 10-20% glycerine infused with allantoin into my fat based product? I guess I will need an emulsifier? The shea butter is loaded with Vitamin E so it might have enough preservative already. The coconut and olive oil seems to preserve a very long time as well.

Hi Bob. Thank you for your kind words!  Allantoin is soluble in water - I choose to use it in the heated water phase of my products, while others use it in the cool down phase. As for adding it to an anhydrous or oil based product - I don't know how you would do that. You can't add glycerin - it's water soluble - to your oil based product without an emulsifier, and if you're going to go to all that trouble, you might as well make a lotion.

Vitamin E is an anti-oxidant, not a preservative. It retards the rancidity of our oils. If you're using coconut oil, olive oil, and shea butter, you should have a shelf life of one year. If you want it to go longer, add up to 0.5% Vitamin E to the product. But one year is a very nice shelf life. (If you add other things to this product, it can alter the shelf life of your product. I'm only basing it on the ingredients you mention.)

What is it you want from the allantoin? Perhaps there's something else that can add those qualities? If you want an approved occlusive, try cocoa butter. If you want something anti-inflammatory, consider adding something that contains a lot of great phytosterols, like olive oil or rice bran oil, or consider using a bit of another butter, like mango butter. (I realize you use olive oil...)

Join me tomorrow for more weekend wonderings, including questions about coco-caprylate caprate, preservatives for solid hair care products, and using all-in-one emulsifiers!


Lesley said...

I like the "wonderings". This is a great way to learn about other processes and ingredients.

Lise M Andersen said...

hear hear! More wonderings! :)

p said...

Love these questions! It's like a cosmetic chemistry advice column ("Dear Susan"?). :)

Leslie said...

I really, really like this idea!

catherine said...

Re staining, I made an after shower body oil with hemp seed oil...without knowing beforehand that hemp oil is dark green!

I still wanted to use it so used an old beach towel in case of staining. Guess what? The green-colored body oil did not stain my towel. I applied it right after showering and before towel drying.

Has anyone else noticed this?

Anonymous said...

Thanks Susan! I want the allantoin because it has skin-regenerative properties. It is considered the "active ingredient" in Comfrey, also known as knitbone! I use comfrey extract, which makes my cream a beautiful green color (and which doesn't stain anything btw!), but the allantoin won't extract into water or oil. Comfrey has traditionally been used as a poultice, so it is thought that the active ingredient penetrates the skin from contact with the plant.

Check out this interesting looking cream that has allantoin and also a lot of herbs. They seem to use only two emulsifiers- cetyl alcohol and polysorbate 80. Anyway they give a serious breakdown and explanation of their ingredients that you and your readers might get a kick out of.

I guess I'm going for what they claim to have- a daily moisturizer that is healing. One of my creams (shea, olive oil, grape seed oil and coconut oil) with comfrey extract and calendula extract and lavender, thyme and carrot seed essential oils) seems to make sunburn just disappear overnite.

Maybe I will just go for a lotion in my next experiment.

Thanks again and all the best!

Anonymous said...

BTW I just stumbled on this amazing database from Environmental Working Group

Called Skin Deep- it examines all the ingredients in personal care products for toxicity. Amazing. Cetyl Alcohol looks good!

All the best,

Susan Barclay-Nichols said...

Hi Lesley, p, and Leslie! Thanks for the support! I'm going to do this on the weekends from now on because I have the time on Saturday and Sunday to go through all the comments and emails and see what piques my interest!

Hi Catherine! I'm not sure why there is the concern about staining sheets because I've certainly never done that with a normal amount of oil in a product! I've used sea buckthorn - really orange - and refined hemp seed and avocado oil - really green - without problems! I think perhaps some people might use huge quantities of oils on skin or in bed, and staining might be a problem? (I'm thinking massage therapy, not anything naughty!)

Hi Bob! That ingredient list is interesting, but I don't get the bottom comment about "ingredients that make corium 21 special - water". Huh?

We don't use the EWG or Skin Deep databases as a resource around here as their sources are dubious and their posts are filled with huge data gaps that don't seem to stop them from making all kinds of claims about ingredients being harmful. (At one point, they had a warning that you should rinse your mouth out immediately if you got olive oil into it. I'm not joking. I saw this myself. I did take a screen cap of it, but I can't find it since I switched computers.) I've written quite a few posts on this group, and I really encourage you to find a more trustworthy site for your information. I'm sorry if I sound harsh, but I really really don't respect that database at all, and I really want you to enjoy making your products!

Catherine said...

Hi again. I was actually pleasantly surprised that my after shower oil blend did not stain my towel. I was fully expecting it to stain since it was a dark green color. I applied after shower...didn't rinse off...then towel dried. And it didn't stain my old white beach towel. Maybe the oils absorb better than I think?