How Length of Time Spent Stick Blending Affects Fluidity

Updated: Nov 6, 2019


Ultimate Guide to Hot Process Soap- Immersion Blender Etiquette

Someone recently asked me a very simple question that I thought I would address in a blog post. The question was: “Do I have to use my stick blender the WHOLE time when making fluid hot process soap?”


The short answer is no, you do not need to use your immersion blender throughout the entire process, BUT, from all of my experience in making fluid hot process soap, I have found that discontinuing the use of my immersion blender before the recipe has completely saponified results in a batter than is less fluid, compared to if I had continued to use it throughout the entire process. The best way to get a HTFHP (High Temperature Fluid Hot Process) recipe fluid is to use your immersion blender as much as possible, switching to a whisk only during heat expansion and at the very end, if necessary.


You also need to make sure that your recipe is created with an informed HTFHP recipe and the proper HTFHP additives. Without an informed recipe, HTFHP additives and an understanding of the process, you are setting yourself up for failure, disappointment and failed batches. If you follow the directions provided in the Ultimate Guide to Hot Process Soap and make sure that you are using an informed HTFHP friendly recipe, you shouldn't need to use your immersion blender for any more than 4-5 minutes. Anything more than that and there is a "user operated" error.


But what if I don’t have a very good stick blender or there is another reason why I am not able to continue to do this? First, if your goal is to make HTFHP, a quality immersion blender is an absolute must. With any new hobby, you need to ensure that you have the right tools and information necessary to effectively complete your project. Often the immersion blender that you use for CP will not be powerful enough and may result in a very disappointing experience. Our goal when making HTFHP is to increase the rate of reaction, as much as safely possible, and this can’t be done without the proper tools. Your immersion blender should be able to be used continuously for 3-6 minutes. You wouldn’t go golfing with a mini-golf club and expect to do well; it is the same principle when making HTFHP.


Second, if for some reason this just simply isn’t feasible, you can still make High Temperature Fluid Hot Process if using an informed recipe, but it may not be as fluid. The two primary components that increase the rate of reaction in fluid hot process soap making are continuous mechanical mixing and increased temperature. By reducing continuous mixing, you must maintain a high temperature and use this to your advantage so that the heat can take over some of the “slack” that discontinuing the use of your immersion blender creates. There are several options that will allow you to do this:


1. Add your lye solution to your heated oils and use your immersion blender to mix until trace. Cover your recipe with plastic wrap and wait for it to expand from the heat, blend, and then re-cover. Continue to repeat these steps until your recipe no longer expands. (You absolutely must be aware of the temperature during the process, if the temperature falls below a certain point, there will not be enough heat to increase the reaction rate and you may end up having to add more heat or switch to LTHP)

2. Add your lye solution to your heated oils and use your immersion blender until heat expansion begins. At this point, switch to using your whisk and continue mixing until the process is complete. Cover with plastic and continue with the directions as usual. (Again, make sure you that are aware of the temperature of your recipe throughout the entire process!)



When I take the time to soap, I will often set aside a few hours and create several different batches at once. This means that my immersion blender gets put to good use. I ensure that I use it as much as possible, without burning out the motor at the same time. Every recipe that I make using HTFHP, even the 25lb batches, I use my immersion blender throughout the entire process, switching only to a whisk if there is an expansion due to heat, and at the very end of the process if necessary. My favorite recipes allow me to use an immersion blender from start to finish, but because I like to use different ingredients and oils that aren’t always HTFHP friendly, this isn’t always going to be the case.


Please view the "Immersion Blender Etiquette" video for directions to see how to effectively use an immersion blender and whisk to ensure that your recipe is as fluid as possible


Do you have any suggestions or tips on how to use your immersion blender more effectively? Share below!


For more information about soap science, recipe formulating, hot process soap and fluid hot process soap, be sure to get your copy of The Ultimate Guide to Hot Process Soap today by visiting our bookstore now!