Monday, September 26, 2011

Question: How do I modify the recipe when I add or subtract an ingredient?

This question comes up a lot, and although I thought I'd covered it before, I figured this question deserved its own post!

How do I modify a recipe when I add or subtract an ingredient? For the most part, we take the same percentage from the water in the heated water phase. A few examples...

You add 10% aloe vera to a lotion. Take 10% away from the water amount.

You add 2% panthenol to a shampoo. Remove 2% from the water amount.

You add 2% panthenol, 5% liquid green tea extract, 2% hydrolyzed oat protein, 0.5% polyquat 44 to a conditioner. Remove 9.5% from the water amount.

If you use 20% lavender hydrosol, 10% aloe vera, 10% chamomile hydrosol, 0.5% powdered grapeseed extract, 0.5% powdered honeysuckle extract, 0.5% allantoin, 0.5% MSM, 2% niacinamide, and 2% salicylic acid, you would remove 44% from the water phase.

I realize many of the ingredients in this last example are powdered, but that doesn't change that we remove the additions from the water amount. This will change the consistency of the product - you've added 6% powders and removed 6% water, which will likely make it thicker - but you've kept the recipe relatively the same.

It doesn't matter if your added ingredient is in the heated water, heated oil, or cool down phase. You still remove the addition from the water amount.

A final example: You add 5% oils to a lotion. Remove 5% from the water amount - AND recalculate your oil phase. You have 5% more oil in your product, so you must recalculate your emulsifier. For Polawax, you would add 1.25% more, and remove a total of 6.25% from your water phase. (If you are using an emulsifier other than Polawax, you'll have to recalculate according to the manufacturer's suggested usage rates.) For the most part, it's easier to substitute one oil for another rather than doing all the recalculating, but I encourage you to add more oils and recalculate as it is one of the first steps to making your own recipes!

If you want to know more about modifying lotions and how to add or subtract ingredients, I wrote about it fairly extensively in the learning to formulate series few months ago. I'm writing this on my iPhone so I can't link, but if you can't wait for me to update this post tomorrow, scroll down and look for formulating in the labels. It's one of the first few posts.


Tara said...

I think the best way to make a recipe is to list all of your ingredients (MINUS the water) in precentages, then QS with water. This way the amount of water is merely the subtraction of the total amount of ingredients from 100%.

Cory said...

Great explanation!

Along similar lines, would you be willing to explain in a future installment how to simplify an existing recipe?

I'm interested in making a cream like this one:

But that's an intimidating list of ingredients for a beginner, to be frank! For a more basic version, do I really need five emollients and three emulsifiers?

To simplify such a recipe, could I add up the %s of ingredient groups? (So add up the %s of emulsifiers to 13.7% and use that amount of, say, Polawax or another emulsifier of choice?)

Or is that totally wrong-headed?

Thanks so much!

Leman said...

Thank you Susan, this is a great post and great examples!

Cory, I have seen that recipe and printed out! I like to try it too but perhaps once I mastered some of Susan's recipes! I am very interested in AHA type of creams. I'd like to be able to add lactic, glycolic and salicylic acids to creams/toners.
Cetyl Alcohol is not an emulsifier but a thickener though there are still two emulsifiers in the recipe!

Susan Barclay-Nichols said...

What interests you about that cream. I'm curious if it's something specific - salicylic acid, the emulsifier, the emollient - or if you have heard good things about it. You can add salicylic acid or AHA to any recipe you wish - just add it at the appropriate stage and ensure your pH is correct! Click on the links in the ingredient listings on the right hand side for AHA or salicylic acid.

Cory said...

Hi, Susan!

It's the Salicylic Acid. To be honest it just now occurred to me that I could take a simpler lotion recipe and add Salicylic Acid to it.

I'm sure this will seem silly to an experienced and knowledgable crafter such as yourself, but my mind reels when I try to contemplate formulating a recipe myself, with what seems like thousands of choices...although that's probably good for the old brain, eh?

I'm reading through your archives to gain a better understanding of the processes involved with formulating! I'm reading your posts about basic lotion-making, and trying to understand what each ingredient does and how to build out from there to a recipe I would want to use. Thanks for the wealth of info!

Leman said...

I'd like to see more recipes for lotions and formulating lotions. And I am hoping you would go back to your posts on duplicating products sometime in future!.

An e-book on formulating from scratch would be superb!! How about an e-book on duplicating products?

I'd like to donate sometime soon to recieve your e-books. What I have been wondering (this may sound silly I know!) whether you include the comments on your posts in the e-books! I find them incredibly useful, sometimes after reading a post I would have questions in mind, than when I read the comments I find the answers in the comments!

Susan Barclay-Nichols said...

Hi Leman. I haven't included the comments but it's a great suggestion for future e-books! I learn so much from these comments and I'm sure that others will as well. Thanks for the information.

And thanks Tara. The water q.s. is always a great idea - as long as we remember to write the number down before we get into the workshop. I hate having to do the math when I'm in the middle of pouring! (But I love the doing the math any other time!)

madux said...

Hi, Susan

I have trouble getting specific amount in my shampoo recipe, i wanted to get 250 ml but ended with about 220 ml of shampoo. I wonder if that is because of the powdered ingredients... Could you explain to me why that happened and how to fix it?

Heated water phase - 61% distilled water,15% SCI,5% Cocoamidopropyl betaine,4% glycerin,3% hydrolized oat protein,4% Glycol Stearate,1% Chondrus crispus(for thickness)

Cool down phase - 4% honeyquat, 2% panthenol, 1% preservative

Susan Barclay-Nichols said...

Hi madux! Check out today's Friday Wonderings to see the answer. The short answer is that it has to do with density of our ingredients!

Emma said...

Great post,

Would this be the same concept for silicones?

Susan Barclay-Nichols said...

Hi Emma. For what kind of recipe? Generally, no. They are considered as part of the oil phase v