Lotion foam

[Mschwartz]

I have developed a lotion recipe that absorbs well and is the thickness I like. My problem is when stick blending the mixture there’s always foam that builds on top. I’m not removing the wand out of the liquid but it’s foamy on top every time. I have been scraping it off the top but it’s a pain and was wondering if there’s a way to keep the foam tamed? Thanks

 

[AliOop]

If you want to list your recipe with all ingredients and additives, that might help us pinpoint the issue. It's typically the emulsifier that causes foam, because most of them are also surfactants. The more emulsifier used, the more foam there will be during the blending, and the more "soaping" effect you will get when applying it to your skin. But other ingredients can contribute to this, too.

Also, do you burp your stick blender after putting it into the mix, and before blending begins?

My lotion doesn't get super foamy while blending. When bubbles do appear, I use the spatula to smush most of them against the side of the bowl. The rest of them dissipate as the mixture cools. Have you tried letting the foam sit to see if it dissipates during cooling?

 

[Mschwartz]

If you want to list your recipe with all ingredients and additives, that might help us pinpoint the issue. It's typically the emulsifier that causes foam, because most of them are also surfactants. The more emulsifier used, the more foam there will be during the blending, and the more "soaping" effect you will get when applying it to your skin. But other ingredients can contribute to this, too.

Also, do you burp your stick blender after putting it into the mix, and before blending begins?

My lotion doesn't get super foamy while blending. When bubbles do appear, I use the spatula to smush most of them against the side of the bowl. The rest of them dissipate as the mixture cools. Have you tried letting the foam sit to see if it dissipates during cooling?

My recipe is: 70% distilled water, 5% emulsifying wax, 3% stearic acid, 5%Shea butter, 5% cocoa butter, 6% sweet almond oil, 5%olive oil, and 1% preservative. The foam does dissipate some when it sits. I’ll try the burping the stick blender better.

 

[AliOop]

Assuming you are adding the preservative after the initial emulsion has sufficient cooled, I don't see excess emulsifier or anything else that would cause excessive foaming. Sorry I can't be of more help; hopefully my "expert" tip of smashing the bubbles and then letting the rest dissipate will work for you, too.

 

[Mschwartz]

Thanks for the reply. You ever try putting honey in your lotions?

 

[lsg]

"In some formulations, using more than 8% of alcohols and long-chain esters in association with self-emulsifying waxes is enough to provide what we call a “foaming effect.” Formulators may face this problem while developing a product that contains a high amount of oils, as they will certainly need enough emulsifier to prevent creaming."

Source: Foaming Effect in Skin Care Emulsions

 

[AliOop]

Thanks for the reply. You ever try putting honey in your lotions?

I haven't tried it yet. In the back of my mind, there is something about honey, which is similar to aloe vera, in that both are high in electrolytes, which makes them harder to preserve, or maybe it was that the pH gets out of whack? I can't remember exactly, and I'd love to learn more about it if you research this!

 

[Zany_in_CO]

wondering if there’s a way to keep the foam tamed?

If you do the "Heat & Hold" method like I do, you can "tame the foam" by preparing an ice bath ahead of time. The batch starts out watery (foamy) but thickens as it cools and the foam is less likely to form

1. Heat water phase 10 minutes to 170°F (77°C), hold for 20 minutes.
2. Heat oil phase 2 minutes to 170°F (77°C). Gently stir. Cover and hold.
3. Combine. Keep stick blender near the bottom and blend.
4. Stop blending briefly. Place bowl into a cold water bath in sink. SB until thickened, incorporated and cooled. (about 2-3 minutes.)
5. Check weight*. Add more water if necessary.
6. Place back into the cold water bath and mix to 95°-100°F (35°-38°C) this should take no more than 1-3 minutes more. Remove the pot from the water and place on the counter.
7. Add preservative and mix well. Add fragrance now or later. Let set until completely cool. Cover lightly with paper towel.
8. Pour into Ziploc. Snip corner to dispense into containers.

* Weigh bowl ahead of time.

 

[cmzaha]

Honey is a bug food and very hard to preserve. When homemaker or artesian, for lack of a better word, is making lotions is much better to keep them very simple without a lot of additives, since we do not usually have the knowledge or access to a full testing lab setup. Many additives such as proteins and sugars lend to bacteria and mold growth in lotions which we are not equipped to test for the long term. Sending each batch and tweak out for challenge testing becomes very expensive. Although you might preserve your lotion which is not an option not all preservatives work under all circumstances which is why it is best to keep your lotions simple, using as little bug food as possible.

Sorry I veered off from the original question. Like Zany I use the Heat and Hold and an Ice Bath method. I also have one other addition to that method because I also made large batches of lotions. When I heated my water I heated extra water, measuring my heated water before I poured it into my heated oil mixture, I would chill some of my heated water to add in after mixing my oils after reaching emulsion, to jump-start the cooling. I would use approx 1/4 % of my water for cooling, too much and I would risk my emulsion breaking, depending on how much water is in my formula.

 

[Zany_in_CO]

You ever try putting honey in your lotions?

I sub honey for the glycerin in my lotion for personal use.

Due to Colorado's Alpine Desert Climate (low humidity) straight glycerin stings my hands -- except when it's rainy or snowy. Then it feels nice. Glycerin is a humectant. As such, it draws moisture from the air to your skin. If there isn't enough moisture in the air, it takes it from the skin. YIKES!

Honey, on the other hand, is soothing, when it's wet or dry. It is known to have the longest shelf life of anything on your pantry shelf. (I learned that watching Jeopardy! LOL)

SHORT STORY
I gave a bottle from my personal stash to some friends. When I visited them a year or two later, there my lotion was in the Guest Bathroom! I was SO surprised. I had to sniff it. It smelled like the day it was made. I used it and had no negative reaction.

For all its syrupy sweetness, honey is one of nature's most hard-working creations; rich with antioxidants, it is both a powerful humectant, meaning it's able to draw and seal in moisture, and packed with potent antibacterial compounds...
Source: https://www.nytimes.com/2022/02/09/t-magazine/honey-beauty-moisturizer-oil.html

That being said, @cmzaha 's words about "bug food" are well taken. You don't want to add anything to your lotion that may cause problems down the road. It's not worth the worry.

 

[Mschwartz]

I raise bees which actually got me into soaps and other skin care products so I have lots of honey. I’m using germall plus as a preservative but have read that honey feeds bugs as well that’s why I was wondering. I seen some stuff stocked local that was goat milk lotion and honey and they specifically listed optiphen for their preservative. I thought milk lotion didn’t last no matter what the preservative.

 

[AliOop]

Oooo, you are blessed; I'd love to raise bees someday.

With a strong preservative, I think you can add small amounts of milks and honey for label appeal. Susan Barclay Nichols of the SwiftCraftyMonkey blog mostly recommends honey powder, but she does have an older (2012) lotion recipe that calls for 4% honey in the heated water phase. Here are her words about including honey in products with water in them:

You have to preserve anything with honey very well. As we know, it’s not an effective preservative when we add water to it and it’s going to break down when we heat it, so we need to choose our preservative well. I normally like liquid Germall Plus as a preservative, but I use Germaben II as it is great for things that are hard to preserve, and anything containing honey or other botanical ingredients is generally hard to preserve. You will have to use a broad spectrum preservative or combine two non-broad spectrum preservatives to ensure the product doesn’t become contaminated.

 

[Mschwartz]

Thanks for all the advice. Bees are definitely a lot of fun.

 

[justjacqui]

If you are not opposed to silicone (not natural), a small amount of dimethicone (0.5 -2%) can help with foaming as it also acts as an antifoam.

If you are planning on making a lot of lotion maybe look at investing in an overhead stirrer rather than using a stick blender.

Hope this helps