5 Reasons to Rebatch Handmade Soap (with 4 ways to do it)

Understanding Rebatched Soap vs. Milled Soap

Soap-making is an art that has evolved over centuries, and with it, various techniques have been developed to enhance the quality, texture, and longevity of soap. Two such methods are rebatching and milling, which are often used by soap makers for different reasons. In this post, we’ll explore what rebatched soap is, explain what milled soap means, and why you might want to consider rebatching your soap.

What is Rebatched Soap?

The most common form of Rebatched soap, also known as hand-milled soap or French-milled soap, is essentially a process of recycling soap to improve its consistency and performance. The method involves grating existing soap bars, melting them down, and then adding additional ingredients such as fragrances, colors, or moisturizers before molding them into new bars. (We’re going to talk about a few other rebatching methods for handmade soap down below too!)

Why Rebatch Soap?

There are several reasons why soap makers choose to rebatch their soap:

• Quality Control: If the initial batch of soap didn’t turn out as expected, rebatching allows the maker to correct any issues without wasting materials.
• Customization: It provides an opportunity to add special ingredients that may not survive the saponification process in cold or hot process soap making.
• Texture Improvement: Rebatching can result in a smoother, more uniform texture if the original batch was coarse or uneven. Note: The final product will have a rustic appearance similar to hot process soap.
• Salvaging Soap: Sometimes, soap batches can have minor aesthetic flaws, or they can totally seize up into a seemingly ruined mass of ugly soap! Rebatching helps in salvaging these soaps and turning them into perfectly good, sellable products.

4 methods for rebatching soap are detailed below including tips on getting a smoother rebatch, and ensuring the soap is safe for use.

What is Milled Soap?

A traditional rebatch is very similar to a milled soap, but it’s also quite different!

Milled soap refers to the process where soap (shredded like handmade soap for rebatching) is passed through a series of rollers (mills) after the saponification process. This milling process thoroughly mixes the soap’s ingredients, which helps in achieving a consistent and homogenous product. Commercial soap manufacturers often use this technique to mass-produce soap bars that are uniform in shape, color, and texture.

A typical handmade soap maker would be be capable of creating a true bar of milled soap simple due to the equipment required.

Benefits of Milled Soap

• Longevity: Milled soaps tend to last longer than their unmilled counterparts because the milling process compresses the soap, making it denser and harder.
• Luxurious Feel: The milling process can create a smoother, more luxurious-feeling bar of soap (well, that’s what some say… I’m partial to my handmade soaps and, to me, they are the most luxurious bars around!)
• Consistency: Milling ensures that fragrances, colors, and other additives are evenly distributed throughout the soap.

Ok, let’s get back to rebatching handmade soap!

Why You Would Want to Rebatch Handmade Soap

Rebatching is particularly appealing for small-scale soap makers or hobbyists who want to refine their soap without the industrial equipment required for milling. Now, admittedly, some soap makers dread rebatching… possibly because they feel they are trying to “save” a batch that failed for various reasons (be it an undesired scent, color, design, or an omission of an ingredient) and don’t want to remember the “fail”.

But another reason to rebatch soap is to utilize soap scraps! Those end pieces, shavings, and other “leftovers” from the production process that would otherwise go to waste.

Let’s explore a few rebatching methods and discuss a few things to keep in mind when rebatching:

4 Methods to Rebatch Handmade Soap

There are four basic methods to rebatch handmade cold process and hot process soap:

1. A standard rebatch – melting down and remolding.
   As mentioned above, this is simply melting down existing soap with minimal additives such as a small amount of liquid or additional superfat.
2. A partial rebatch – melting down with new oils and making a new soap.
   While similar in concept to a standard rebatch, only a portion of the final soap comes from old soap (hence the “partial” part of the name).
3. Confetti soap or Ciaglia – types of cold process rebatching.
   These involve incorporating soap shreds of soap into a new patch of cold process soap for various design effects.
4. Salting out soap – some cool science to extract the saponified soap from any impurities.
   This method is probably my favorite as it can literally save any “whoopsies” soap you end up with… and turn it into floating soap, laundry soap, or hand soap powder which is perfect for traveling!

5 Reasons to Rebatch Your Soap

1: Lye Heavy Soap

If your soap is lye heavy, the safest saves are salting out or a partial rebatch. Sure, you can do a standard rebatch… but you have to be very diligent in blending and ensuring you don’t end up with any lye pockets. I much prefer salting out lye heavy soaps.

2: Excess Oil (high superfat)

If you’re rebatching because you ended up with too much superfat in your soap, I highly recommend the partial rebatch. Salting out is suitable as well, but a partial rebatch is more time efficient. Wondering why you might have too high of a superfat? You could have miscalculated your formula when resizing, Maybe your sodium hydroxide was too weak, or maybe you “whoopsie” add too much of one of your oils. Regardless of why your soap is soft and oily from too high of a superfat, a partial rebatch will fix it up in a jiffy.

3: Fixing Ugly Soap

If there’s nothing wrong with the soap, but it’s just doesn’t make you smile, you can use any method to rebatch it. Heck, you could even just use it as is! Maybe close your eyes while showering and imagine it’s the perfect most beautiful bar ever? But seriously, I get it. We want pretty soap. And, sometimes turning something ugly into something beautiful is extremely rewarding. And let’s face it, we’ve all made ugly soap at one time or another! I typically use my ugly soaps to make my Christmas Coal soaps. I’ve included this recipe in the partial rebatch lesson of the Hot Process Rebatching Tutorial… but you’ll also see a great save of ugly soap in the Ciaglia lesson of the Cold Process Rebatching Tutorial.

4: Smelly (or not so smelly) soap

If the only thing wrong with your soap is the aroma you have a few options. A partial rebatch will let you smoothly melt down the soap and either dilute the aroma or you can add more aroma in after the cook. Grating the soap up for a confetti bar provides the same option – allowing you to adjust the scent with a new soap base. And then finally, salting out soap can remove all of the aroma.

5: I forgot to add something, HELP!

If you realize that you neglected to add something to your recipe, there are oodles of options for you.

• If the something your forgot resulted in a lye heavy soap, I really do recommend salting out your soap, but a well blended partial rebatch with light shreds can work too.
• If you forgot to add a color or aroma, consider any of the rebatching options to turn it into something new. You’ll add the color or aroma at the appropriate step for each method.

If you’re not sure what’s wrong, and you just know you forgot something, salt it out! That’s the safest way to handle any unknown in the soapy world.

The following chart is from my Rebatching Soap tutorials, and will help you figure out which method will be most suited to your needs:

The Issue:	Standard Rebatch (hot process)	Partial Rebatch (hot process)	Confetti or Ciaglia (cold process)	Salting Out
Lye Heavy Soap (crumbly soap)		✅		✅
High superfat (oily and soft soaps)		✅		✅
Ugly Soap	✅	✅	✅	✅
Smelly (or not smelly enough) Soap		✅	✅	✅
I forgot to add something, HELP!	✅(sometimes)	✅	✅ (fragrance or color only)	✅
Left over ends and shreds	✅	✅	✅	✅
I don’t know what I did wrong				✅

Ready to Try Rebatching?

If you want to go deeper into rebatching handmade soap, I have several resources that can help — whether you’re trying to rescue a batch, intentionally create rebatch soap, or learn the difference between cold process and hot process rebatching techniques.

Want the full rebatching system?

My Rebatching Masterclass Bundle walks through both cold process and hot process rebatching methods, including troubleshooting, texture, moisture control, and working with difficult batches. By the end of the course, you’ll be able to take a failed batch and turn it into everything from spa quality floating soap to super powered laundry soap!

If you’ve ever wondered:

• why some rebatch turns smooth while other batches stay chunky,
• how to fix dry or crumbly rebatch,
• how much liquid to add,
• or when a batch is actually worth saving…

…this class was made for you.

Prefer to watch free rebatching demonstrations first?

I also have free rebatching soapmaking video tutorials available if you’d like to see the process before diving into a full class.

Still not sure if you need to rebatch your soap?

Sometimes you need to dive into the problem a bit more, and learn how to prevent common soap problems before they happen. If your soap is lye heavy, dry, seized, separated, overheated, or otherwise misbehaving, my soap troubleshooting tutorials can help you figure out what went wrong.

Happy soaping! 🧼