I went to the local Jungle Jim’s International Market fully intending to buy the ingredients to create basil and lemon essential oils for my next batch of soap. In the bargain bin of the produce section, I came across a surplus of limes and tarragon looking for a caring owner. I looked at them and thought, “Why not?” The lemon and basil soap can wait until a different time. This time belonged to the tarragon. It just felt right. Let me tell you how this chance encounter turned into my first batch of shampoo bars.
Tarragon + Lime = ?
I was excited to experiment with these products in a homemade soap. Tarragon’s scent is reminiscent of licorice. It is subtle, but enticing. The herb is most commonly encountered in tarragon vinegar. The benefits to your skin include improved circulation and anti-bacterial and deodorizing properties. Limes are acidic and contain a significant amount of vitamin C. Their natural properties fight dandruff while nourishing your scalp and hair follicles. Plus, the acidic properties stabilize the pH balance in the soap toward your body. Interestingly, the properties of the tarragon and lime provide great benefit to the hair. It was a total fit. I decided to create my first batch of shampoo bars.
The next day was a rainy Saturday. The indoor time was great for making essential oils and watching college football. The tarragon oil was first. I blanched the herbs, blended them, heated the mixture to infuse and into the refrigerator. Next, I juiced the limes and set aside the juice to include with the soap recipe later. The rinds went into the top of a double boiler in coconut and almond oil for 3 hours. Once infused, the oil was strained and also went into a cool, dark location. My essential oils were now ready for making soap. I really cannot believe Georgia let Alabama come from behind and beat their football team again.
Tarragon Oil pre-emulsification 
Tarragon Oil final
Creating a Recipe
Monday, I went about developing the base recipe for making shampoo bars. I leveraged my spreadsheet in Google sheets. It contains oil properties, saponification values, and the like. I started with the major oils, which usually include olive and coconut types. Since I was going with a shampoo bar, I upped my quantities of coconut and decreased the olive oil content. I did this to improve the hardness of the bar as well as its ability to lather and clean your hair and nourish your scalp. It can be potentially drying when used solo so that is where the olive and almond oil comes in. These oils moisturize the hair and scalp and balance the coconut oil. Almond oil contains significant amounts of vitamin E.
To finish the oils in the recipe, I decided to include castor and jojoba oils. Castor oil lathers well. nourishes hair and scalp, adds shine and promotes new hair growth. Plus, for men, it is great conditioner for facial hair. Lastly, the jojoba oil creates harness in the bar and is nourishing and protective to your skin. From my research, its chemical make-up is similar to the oils created by our bodies. Including the oil in our recipe attempts to help the skin replenish its own oils.
Prep Time
Now, I was set with the recipe and ingredients. It was time to get started. I was going to need the following:
Distilled water and real lime juice
Sodium hydroxide (lye)
Coconut, olive, almond, castor and jojoba oils
Homemade lime and tarragon essential oils
No colorant
Crock pot, glass jar, mixing instruments, stick blender, molds
Preparing the Alkaline Base
I needed 13 ounces of liquid to accurately mix with the lye, so I started by mixing 9 ounces of distilled water with the lye. I planned to add 4 ounces of pure lime juice later. Working in a place with good ventilation, mix the lye into the water in a glass jar and mix until the liquid is virtually clear. Never pour water into the lye. That will cause a volcanic reaction (at least that is what I have heard). Insert a video? The lye water mixture will heat up. Let it cool while you measure out and heat up your oils.
The Hot Process
In a crock pot, melt all oils on high. When all oils have melted completely, bring in your lye, add the lime juice and add all of the liquid to the melted oil. Fire up your stick blender and begin mixing the oil and lye liquid. Blend for a minute and then turn off your blender for 30 seconds but keep manually mixing. This will keep your blender motor from overheating. Repeat this process 3-4 times until your mixture reaches trace. You will know when the mixture dripping off your blender leaves a trace on the surface. Reduce heat to low and cover.
The heat triggers the mixture to now go through the saponification process. The lye reacts with the oils to create chains of soap and alcohol, which evaporates. In a series of stages, the mix will start to look like applesauce then mashed potatoes. As it combines, you will notice liquids collect in the middle of the pot while the oils turn solid around the sides. It is important to stay close by as the soap chain climb up the side of the pot. There is potential for the mixture to boil over.
After about an hour, the soap chains have formed, the liquids have dissipated, and you need to start testing for doneness. The mixture needs to register a pH < 10 to be safe to use. Most soaps have a pH between 8 – 10. You can use one of two methods to determine doneness: 1) a zap test, or 2) pH test. The zap test is taking the mixture and putting it to your tongue. If you get zapped, you need to cook out more of the lye. If not, you are good. The ladies in my house will not allow me to use the zap test, so I use pH strips. When the strips register <10, I turn off the heat and let my mixture cool for a couple of minutes.
Adding the Final Elements
Once cooled, I add the essential oils and mix in. If I were using colorant, I would add at this time also. You add at the end so the heat does not cook your ingredients. This is why some people use the cold process for making soap. It is gentler when adding coloring and essential oils. The main downside is that the saponification takes place with time and aging, called curing, instead of through heat. This process will take 6+ weeks to complete. During the cure process, the saponification process completes, the excess water evaporates and the soap chains harden and crystallize. In hot process, most people let the soap cure for 1-2 weeks, although it could be used right away from a chemical standpoint.
OK, so all ingredients have been added and the cooking is complete. The mixture may now be put into molds. I have found it is easiest to use a loaf mold for the majority and several individual bars to cure and use most quickly. I hate to wait. The bars cure for a week and then they are ready for sampling. The loaf is allowed to cool for the day and then heads to the basement to cure for 2-3 weeks. I recently bought the mold pictured below (affiliate link) and it functioned very well.
Positive Outcomes
I enjoyed conducting the research on the oils to use to obtain the characteristics I am trying to bring out. I found the lye calculations from the saponification values relatively easy to calculate. The logistics of choosing your ingredients and manipulating the recipe make the combinations endless and add to the intrigue and learning process.
I consider the essential oils that I made to be more of scented oils. It was difficult to get to the concentration levels I wanted with the process outlined above being executed in my kitchen. That said, the oils have a nice aroma and that did carry over to the soap. I think with tinkering, I could only improve the process. Plus, doing it at home, opens the opportunity to bring home anything from the produce section and incorporate it into a home product, within reason.
Improvement Opportunities
I will be investing in a digital pH meter. The strips are challenging to use and I don’t think they are accurate enough. I fear I overcooked my batch and I would like to avoid that feeling in the future. For under $15, I have seen digital meters. I will research and have a product link in future articles.
My picture taking during the process clearly has opportunity to improve. I am doing my best. After all, you can only run as fast as you can run. I understand the aesthetics are lacking but I hope you are able to follow the process from beginning to end. Additional efforts will focus on improving this aspect in future articles.
Final Thoughts
I thoroughly enjoy the creativity, development of an idea, and the hands-on application of making soap. It may be as simple or complex as you want it to be. I am currently mulling my next step. Will it be further down the soap making path or what other products do I use that may benefit from a natural creation? I know cold process soap will happen, but what else?
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