Superfat? How Dare You. An Intro To Soap Making Terminology - Soap Cult Australia

Superfat? How Dare You. An Intro To Soap Making Terminology

Soap Terminology for Non-Soap Makers

            A glossary of soap making terms for lovers of handmade soap

Connoisseurs of handmade soap often experience soap terminology overwhelm when they try to learn more about handcrafted soap. Even a basic google search result tends to only show maker-level information, which can be overwhelming.

In this blog series, we'll learn about common soap making terms every soap cultist should know about. 

Today's term, is "Superfat" 

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What is Superfat?

Superfat sounds like something a mean girl would say at school but in soap making, it's the reason why handmade soap (such as Soap Cult Australia's) feels so good on the skin.

Sometimes referred to as a lye discount, superfatting is a technique where more butters and oils than are needed to make soap, are added to the soap batter. 

These excess butters and oils are not saponified (see more in Saponification, coming soon!) and remain, almost free-roaming within the finished and cured bar.

Each time you wash with the soap, a tiny amount of those butters are oils are left on the skin, giving a gentle, conditioning feel after you rinse and dry. 

How much Superfat does a soap have?

Most soap makers leave anywhere between 5% to 12% superfat in their soaps, with some formulas needing as high as 20% super fat. 

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The percentage used will depend on the specific formula. For example, a soap maker would have a different superfat and also choose different oils and butters for the formula depending on:

  • which part of the body the soap is intended to clean (hands, body, face etc.)
  • what skin type it's intended for (mature, oily etc.)
  • region or climate the soap will be used in (you'd want a more moisurising soap in a cold climate and less in a hot climate)

Can a soap be Superfatted with a specific butter or oil?

You can't really choose which oils and butters remain in the soap because the lye does what it wants and consumes all it can.

Occasionally some soap makers will say their soap has been superfatted with a particular oil (usually something luxurious for label appeal) but it's not really possible to know which oil remains.

That is, unless the soap has been made using the Hot Process Method and the superfat is added after the cook (see more in Hot Process, coming soon!)

In any case, enough of those yummy, skin loving butters and oils remain in the finished soap to condition the skin. 

And that is why, on Wednesday's, we superfat.

(yeah, that's a Mean Girls reference. You can superfat any day)

What happens if a soap isn't Superfatted?

Aside from the benefits to the skin, a superfat is like a cushion in a soap formula. Without that little cushion, it can be strong and overly cleansing.

Sometimes you want that, like in a dish soap for example. It's no use having a bunch of extra fats and oils in the sink when you're trying to remove them from your dishes.

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In a commercial setting, where soap is made in massive bulk quantities, not only is a superfat not added, they'll remove the glycerin that's naturally formed when  soap is made and on-sell that as a seperate ingredient for profit.

Anything sold as "triple milled" or "beauty bars" won't have a superfat. I suspect there's a few reasons for that.

  • Commercially made soap is made to a very specific formula by contract manufacturers
  • Profit and cost per bar is Queen so that's why you'll often see exactly the same ingredients across a range of different brands. The only difference is typically the scent and wrapping
  • Over time, a superfat can possibly go rancid if the soap isn't stored in the right conditions or isn't used soon enough. When you're making massive  commercial quantities, warehousing with distributers and sending it out to retailers to sell for goddess-knows how long, a superfat can be a liability so they don't do it.


So, that's Superfatting for you

Weird terminology but that's what soapmakers call it. And that's why a superfat is so important in handmade soap. Our skin needs to be clean, sure, but it also needs to be cared for and not have its moisture stripped out.

Any good soapmaker will ensure their formula/s have the right balance of butters and oils (more on the Fatty Acid profile in another post) alongside the right superfat for that particular soap.

However, don't expect a soapmaker to share that information with you. It'd be like asking what's in the "secret herbs and spices".