A case study which provides a simplified, easy-to-understand, proven method for achieving crystal clear liquid soap with every batch. Liquid soap making is an exact science and if the five underlying principals are followed, in the proper order, it's really difficult to mess it up!
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Step 1: It's Just Not That Hard!
Liquid Soap Lady takes the guesswork out of making liquid soap. These techniques will show you how to make your own liquid soap, in easy-to-understand terms. IT'S JUST NOT THAT HARD! If Liquid Soap Lady can do it - Anybody can do it! There are numerous websites dedicated to cold process soap making, bar soap. But none that are dedicated to hot process soap making, liquid soap. Liquid Soap Lady is here to remedy the situation with a website dedicated to everything liquid soap making. Recipes, tips, blog to answer questions, instructions, education. The one place on the web to get ALL of your liquid soap questions answered, by a liquid soap making community.
How Liquid Soap Lady's 5 principals will take the guesswork out of making your own crystal clear liquid soap. Fifteen years ago when I first wanted to learn how to make liquid soap, there wasn't much information on the subject. A few books that were good, but very technical and difficult to follow. But I was determined, and after much reading and re-reading, taking notes, keeping a notebook/journal of my liquid soap making trials and experiments. I came to realize there are five guiding principals to making a perfect liquid soap. 1. Oil Selection, 2. Determing Lye Requirements, 3. Cook time and temperature, 4. Proper weighing and measuring of ingredients, 5. Dilution rates. Once I realized what they were, I then devised my own simplified version of liquid soap making. I have achieved awesome results! I have made great lathering bubble baths, that lather even in hard water! I've made absoutley wonderful shower gels, that are thick and creamy as well as moisturizing. My hand and dish soaps, create tons of lather and are non drying to the hands. Laundry soap that works better than commercial laundry detergents. Pet shampoos that repel fleas and leave my dog smelling wonderful. Like a lot of things in life, we tend to make it harder than it really is......... Nothing would make me happier than showing others just how easy it is to create your own liquid soaps. Replace those chemical laden detergents found on the grocery store shelves with your own liquid soap. Liquid soap making is fun too!! The five guiding principals; 1. Oil selection 2. Determing Lye Requirements 3. Cook time and temperature 4. Correct weighing and measurement of ingredients 5. Dilution rates Once you understand the concepts behind each of these principals you will be creating and formulating or own, unique liquid soap creations! For personal use or for sale to the public. Let's look at each principal individually and discuss how and why it affects the liquid soap making process.
Step 2: Principal # 1 Oil Selection
Oil selection is the number one principal to understand and apply to your liquid soap making project. The oils used will determine the character of your soap. Make it lather well or not. Moisturizing or drying to the skin. Determine it's clarity or cloudiness. The cost of your project will be significantly affected by the oils used. Organic is more costly than non-organic, exotic oils are rare and more costly than widely available oils. As always the choice is yours as to what oils are used in your project.
But there are some important concepts that need to be addressed in order to produce a liquid soap. If crystal clarity is not your ultimate goal, then your choice of oils can be a little more lax. Some oils though, do not lend them selves to liquid soap making. Oils that cannot be used exclusively to produce a liquid soap are; lards, animal fats, they have particles that will not sapaonify, leaving the liquid soap milky, cloudy and causes separations within the soap. Waxes and butters, cannot be used exclusively, they also have constitutients that will not completely saponify. Causing clouding and milkiness of the soap. Maybe useable, but does take away from the beauty of the soap. If waxes, such as jojoba oil, and butters, such as cocoa butter, lanolin and shay are used, they would be a very small percentage of the formulation to prevent clouding of the finished product. Unlike hot process soap making where hard fats, lard, coconut oil, palm kernel oil, etc, are used extensively. To harden the bar, make it more moisturizing and for superfatting. These fats and oils are used in moderation or not at all in liquid soap making, with the exception of coconut oil. Coconut oil is the backbone of liquid soap making, it will be used in almost any liquid soap formulation you make. Why Is Coconut Oil So Popular In Liquid Soap Making? Lauric acid, the principal fatty acid found in coconut oil. Lauric acid is very soluble, makes a great lather with a long shelf life. Coconut oil saponifies quickly, making it easy to work with and produces a crystal clear liquid soap that lathers well. Due to it great solubility, it can produce a thicker liquid soap as it requies less dilution to create a liquid. As with all good things there is always a downside or less desirable element. Coconut oil tends to be drying to the skin. Also it will not thicken significantly with the addition of borax and can cost more than other common oils. So what to do, have a soap with weak lather, but is gentler to the skin? The solution it to combine oils to give your soap the desired qualities. This leads us to the two primary classes of oils, "hard fats and soft oils." Hard fats are considered solid at room temperature; such as coconut oil and palm kernel oil or flakes. These oils are highly soluble, easy to work with and produce a very good thick, lasting lather. Tend to have a longer shelf life and does not get rancid as quickly as soft oils. The downside or less desireable elements of hard fats are they can cloud the soap at high percentages of the formula due to high levels of substances that do not saponify and can be drying to the skin. Soft oils are considered liquid at room temperature; olive oil, sweet almond oil, canola oil, etc. They have a shorter shelf life, best to keep refrigerated. Not as soluble as hard fats, but do provide moisturizing properties and make great shower gels. Combining the two classes of oils will give your soap the desired qualities of clarity, great lathering ability and moisturizing properties. How to know how much to use of each type of oil? This is the million dollar question, and that depends on what type of liquid soap you wish to make. Examples: Shower gel - is best when using a high percentage of soft oils in the formulation, such as 95% olive oil and 5% coconut oil. Will give a nice thick soap that lathers well and provides exceptional moisturizing properties. Hand or dish soap - best using a 50/50 formulation. 50% hard fats and 50% soft oil. Will lather well, and provide a stronger cleaning soap. Bubble Bath - What makes a bubble bath a bubble bath? Bubbles! How do you create mounds and mounds of bubbles? With coconut oil....a formulation with 95% coconut oil and 5% soft oil will produce the best bubble baths. Combined with other additives and a combination of lyes to increase the density of the bubbles. These are examples of the thought process that goes into selecting oil combinations for your liquid soap projects. They are just guidelines and rather simplified, but it gets the point across of how the oils you select will contribute to the qualities you want your liquid soap to have. Can Liquid Soap be Superfatted? Yes, but is is more challenging than with bar soap. There a very few oils which can be used to superfat liquid soap. Most oils will cloud and cause separation of the finished soap. The best and really only oil which can be used as a superfatting agent in liquid soaps is Sulfonated Castor Oil, (Turkery Red Oil). It is very soluble, will not cloud or separate the soap and provides added lubricating properties. I use it rarely, as my soap formulations are quite moisturizing as they are. But if you wish to use it, it is added after the soap has been diluted, used at a rate of 1 to 2 oz to the finished soap, while it it still hot. Fatty Acids Are The Key The fatty acids that comprise each oil are the constitutents that give each oil their own unique properties. Such as lauric fatty acids in coconut oil. Making coconut oil quite soluble and easy to work with. Oleic acid in olive oil, giving olive oil it moisturizing properties and good for the skin. Linolenic acid in safflower oil, giving the lather body and making it a good choice as a shower gel. This link takes you to a discussion of fatty acids and what qualities they lend to your liquid soap. http://www.modernsoapmaking.com/the-most-popular-fatty-acid-profiles-in-soapmaking/ We can thank Kenna of "Modern Soap Making" for this valuable information. This section has discussed the importance of oil selection to determine the qualities you want your liquid soap project to have. It is just the tip of the iceberg as an entire book could be written on oils and their properties and what qualities they can lend to your soap making formulations.
Step 3: Principal # 2 - Determing Lye Requirements
Saponification- the process by which lye and oils with water as a catalysts undergoes the chemical reaction by where the end product is soap.
This then leads us to question.......does lye soap contain lye? The answer is ...no. The lye has been consumed in the process of saponification, it has been chemically transfromed from lye to glycerin and salts, know as soap. Now that we have that out of the way, let's discuss why is it so crucial to get the lye amounts correct during liquid soap making. You ask is it more impotant in liquid soap making than in bar soap making? The answer, yes...and....no.... Getting the correct amount of lye to saponify the oils is important in any type of liquid soap making venture, be it liquid or bar. But we take it bit further with liquid soap making as our goal is to achieve crystal clarity and not wanting the liquid soap to separate into layers. Which are important for eye appeal and functionality. A bar soap can be fudged a little as it remains opaque and supperfatting is achieved much easier which helps eliminate any excess lye in the formulation. We do not have this luxury in liquid soap making. If the lye amount is not exactly right the saponification process will not completely saponify the fatty acids, leaving the liquid soap cloudy and milky and prone to separation of the oil and water layers. It's quite visible to the eye, no hiding the fact! Using a 10% lye excess in liquid soap making is a common practice. There is more to it than meets the eye............ Let's discuss SAP values for just a moment. A SAP value is usually listed on a chart with various oils. There are SAP values for KOH, potassium hydroxide, used in liquid soap making and another SAP value for NaOH, sodium hydroxide most commonly used in making bar soap. The value tells us the amount of each type of lye it takes to saponify a particular amount of oil. SAP Chart These values are approximations based on the oil tested at that particular time. The chracteristics of each oil will vary from season to season, crop to crop, climate, amount of rainfall, etc,. Each oil produced under those conditions will have slight or even major differences from the oils produced at different times. Using a 10% lye excess is just insurance that all of the fatty acids will be saponified and prevent any suprises with your batch. Hydrosols If you use a hydrosol for the water in your lye solution, the plant material from which it was derived will also contain a small amount of oils. The 10% lye excess in the lye solution will ensure this oil is saponfied as well. Neutralization I've read where the liquid soap maker will formulate with no lye excess so as to skip the neutralization phase. This can be done, but neutralizers are used for more than just neutralization of any lye excess. Borax - is a liquid soap makers best friend. It is an emulsifyer, keeps the soap liquid a lower dilution rates, acts as a water softener, a foam booster and will thicken liquid soaps formulated with a high percentage of soft oils. Borax is actually a mild alkali, and since the pH of Borax is lower than that of a newly made liquid soap, it will help lower the pH of the liquid soap to around a pH of 9 to 10. Borax will assist with achieving a perfect shower gel every time. Citric Acid - is a mild acid, it is also used to lower the pH of the newly made soap. It is also a chelating agent, which helps increase the detergency of your soap. Preventing the hard minerals in water from interfering with the cleansing and sudsing action of your soap. pH of Liquid Soap Can the pH of a true potassium liquid soap be lowered to a pH of 7 ? My attempts have resulted in separation and clouding of the soap with a pH of still around 8.9 or higher. Neutralizers can be added up to at a certain point, it will then begin to degrade the soap back into it's basic components of water and oil. Decreasing it's effectiviness as a cleaner and degrading it's eye appeal.
Lye Calculators Lye calculators can be used to determine the amount of lye to use in your formulations, based on the amount of oil and some additives. They are a good tool to use, but lack human reasoning. They should not be totally relied upon to determine your lye requirements. The formula to figure the amount of lye to use is an easy one and quickly computed. It's always best to know how to do it yourself. If your computer is down and you want to make a batch of soap, then what do you do?
Distilled Water For Lye Solution and Dilution Always use distilled water for the lye solution and for dilution of the finished soap paste to achieve a crystal clear liquid soap. Minerals in water will cause clouding of your soap and formation of unsightly sediment. We are now armed with a little more information regarding determing the correct lye amounts for our projects and why it is important. I'm sure they are more questions, than I have time or room for in this case study. Please leave your comments and questions in the comments section of the post.
Let's talk about principal # 3 Cook time and temperature, to see how this determines how well our soap is saponified and how it affects production time.
Step 4: Principal # 3 - Cook Time and Temperature
Your probably wondering what cook time and temperature have to do with anything, you just cook it, right?
When the proper temperatures are obtained when heating the oils. The temperature of the lye solution when added to the oils. The temperature at which the paste is cooked. All these factors significantly reduce the cook and prep time. It means the difference between day and night, literally! If your in no hurry and you want to let the paste cook overnight in the crock pot, that's ok. You can't overcook it and it ensures complete sapanofication of the paste. But if you want to get it done, and get on with the other things in your life. Then proper cooking temperatures will get you done in a timely manner. Heating the oils, using a crock pot is the most efficent way that I've found. Using the stove takes too long. A double boiler is a pain. A 6 quart crock pot is big enough to accomodate a big six pound batch of soap. Some now have a digital temperature reading, which is very handy for measuring the temperature of the oils and paste as it cooks. When heating the oil, melt the solid fats first, then add the liquid oils. Heat all the oils to 160 F/71C.
While the oils are heating, make up the lye solution. Use a large 20 to 22 quart, glass or plastic pitcher. With a lid and a handle. This facilitates pouring the lye solution into the oils while stirring to mix.
A note about KOH, potassium hydroxide. Only pour out what you need for your project when you get ready to add it to your lye water. It absorbs moisture form the air and eventually it will become a liquid and no longer useable. If degrades over time with each opening of the container. Take out what you need and replace the cap to prevent as much moisture as possible from being absorbed. After you've added the required amount of distilled water to your pitcher, under the hood vent, to prevent inhaling the fumes. Put on your gloves and goggles. VERY IMPORTANT, LYE IS CAUSTIC, CAUSES BURNS! Have vinegar nearby, to rub or douse on any lye solution that splashes on you. If you get it in your eyes seek medical attention right away! ALWAYS add the KOH to the water, never add water to the KOH. It will get very hot, fume, hiss and sizzle. Have the vent hood fan on. Leave the lid off the pitcher to allow it to cool down, once it has cooled to 140 F, place the lid on the pitcher and check the temperature of the oils. When the oils are 160 F and the lye solution is 140 F, now it the time to combine them. Using a stainless steel, wire whisk, slowly pour the lye solution into the oils while stirring with the whisk. Being careful not to splash any on yourself. Having the correct temperatures of the oils and lye solution when combining will prevent separation of the finished soap after it has been diluted. Once the paste is diluted it is virtually impossible to correct. Continue to stir alternating between your wire whisk and a sturdy stick blender. The stick blender will create bubbles. The bubbles can slow down saponification so use the wire whisk to stir them down. Be sure the crock pot is on high while stirring as heat speeds up the saponification process. If the oils begin to boil over, turn the crock pot to medium. Keep the heat as high as you can while stirring. This will assist with achieving paste faster. Once paste has been achieved, place the lid on the crock pot to keep the heat in. Turn the crock pot to low. Cooking on a high temperature causes continual puffing, which slows down saponification. Check the paste frequently within the first few hours of cooking. If it puffs up, stir it back down. Constant heat, preventing puffing of the paste and keeping the lid on the crock pot, will faciliate achieving a neutralized soap paste in four hours. A neutral soap paste will be evident as it has a translucent appearance. Test for neutrality by boiling 6 oz of distilled water and dissolving 1 oz of paste, then letting it cool.
If the solution is not cloudy or just very slightly cloudy then it has completely saponified. The use of a pheno solution will let you know if it contains any excess alkali. If you have accurately measured your ingredients and used the proper temperatures, excess alkali is a rare occurance, even with a 10% lye excess. Now we understand why the proper temperature at each phase will assist with faster saponification of your liquid soap project. Which equates to faster completion of your liquid soap project. Let's discuss accurately weighing and measuring your ingredients Really!
Step 5: Principal # 4 - Correct Weighing and Measurement of Ingredients
Maybe in actuality this should be principal # 1. I can hear you! "Yea, tell us something we don't already know!"
Mis-measurement of ingredients is the number one reason why liquid soap making projects fail. Hands down! Do yourself a favor, shell out a few bucks for a decent scale, that has a tare feature. Weighs in oz, lbs and grams. And while your at it get an accurate thermometer. The money you will save in time and wasted materials over the course of a year will pay for these items. Measuring cups, beakers, are also a valuable item to have. Make sure to have at least one measuring cup that will hold up to 64 oz at a time. It will save you a lot of frustration. Always weight in the same units from start to finish. If using ounces, use ounces for all your measurements. If using pounds stay with pounds for all measurements. The same goes if using grams. The unit of measurement does not matter as long as your are comfortable with it and your measurements are accurate. Let's discuss stick blenders, though not a measuring device, it is a time saver. Spending the money on a good commercial stick blender, is money in the bank. After you've burned up several cheaper models you will wish you had bought the heavy duty commercial stick blender to start with. I learned this one the hard way! Weigh your pots and crock pot, write down how much they weigh in a notebook for future reference. This will save a lot of time. Or write down what the pot and crockpot weigh on the pot and crockpot themselves with a permanent marker. Check and double check your measurements! Now we've seen the most common reason for liquid soap making failures, mis-measurement of ingredients. Which equates to wasted time and money. Not to mention undue frustration.
Step 6: Principal # 5 - Dilution Rates, How Is It Determined and What Factors Affect It?
We all want to achieve a nice thick liquid soap. Commercial detergents are thicker, look and smell nice. This is achieved by adding fillers and other chemicals with names we cannot even begin to pronounce. A lot of us want to get away form that, me included!
So how does one achieve a nice thick liquid soap? A liquid soap with a honey like consistency? Very easily............ There are two primary factors which affect how thick your finished soap will be. The rate of dilution and the oils that were used to make the soap. How thick do you want your soap? Do you want all of your soaps to be as thick as honey? Or do you want dish and hand soaps to a little thinner? Laundry soap, thin or thick? Once you've decided how thick you want your soap to be you will then choose the oils that will achieve the desired outcome. Let's start with a 100% coconut oil formulations. This make a very good laundry soap, as it's high foaming, strong cleaner and easily stays fluid with the addition of additives. Coconut oil is very soluble due to it's high concentration of lauric acids. It doesn't thicken quite as well with the addition of borax. But it take less distilled water to dilute the paste. Giving us a thicker soap. It can be diluted at 40% and still remain fluid. Adding 9 oz of distilled water per pound of paste. Lets say we make six pounds of paste. This equates to 54 ounces of distilled water. If a thick crust forms on the top after diluting and dissolving the paste, gradually add more distilled water, 9 oz at a time until total dilution has occured. Dilution rates are from 15% to 40%. The lower the percentage, the thinner the soap. For example a 15% dilution rate, actual soap to water means...... 15% actual or true soap, (paste) to 85% water. A very thin soap. So a 40% dilution rate means, 40% true soap (paste) to 60% water. It is difficult to achieve a higher true soap to water ratio than this. The soap tends to congeal back into a paste at percentages higher than this. Listed is a standard dilution chart, showing how much water per pound of paste is needed to achieve the actual soap percentages. This is just a guideline, as borax will significantly thicken soaps made with a high percentage of soft oils and less water. Actual Soap Water Added Per Pound of Paste
15% 48 oz (3 lbs)
20% 32 oz (2lbs)
25% 22 oz (1lb, 6oz)
30% 16 oz (1lb)
35% 12 oz
40% 9 oz
Now on the other side of the spectrum, lets discuss shower gels. Formulated with 95% soft oils and 5% coconut oil. Very easy to produce a nice thick honey like consistency. The secret, dilution rates and borax. After the paste has cooked to a nice translucent paste. Transfer it to a large stock pot filled with boiling distilled water. The dilution factor equates to 1.5 pounds of distilled water per pound of paste. If you make six pounds of paste then the formula would be 24 oz x 6 = 144 ounces of distilled water. See the difference in dilution requirements compared to coconut oil based paste? Formulations higher in soft oils requires more water for dilution, but the addition of 3 oz of borax to the dilution water befor adding the paste, lets the soap stay fluid at lower concentrations of water and acts as an emulsifier which makes the soap thicker. This will work every time to create a nice thick shower gel. Shower gels can thin in hot summer months. Adding a very small percentage of palm kernal oil, like 1 % of the formulation. Will keep it from thinning when the weather gets hot. How about an average thick hand soap? Let's say it's formulated with 50% coconut oil and 50% soft oils, like olive oil. What do you think the dilution rate would be? More than likely somewhere between 30 to 35% acutal soap to water. Since it contains a very soluble oil and less soluble oil, shoot for a median dilution percentage. You can always add more water if needed, 16 oz at a time. Giving it time to show if it is effective at diluting the paste. If too much water has been added allow the soap to simmer with the lid off for a while and test again. How to test to see how thick the soap will turn out after being diluted? Get a measuring up or spoon. Place it in the freezer. Take it out and place a small amount of the liquid soap on the surface. Cover with plastic wrap and let it cool. This will give you pretty accurate representation of how thick the soap will be once cooled. Experiment, experiment, keep notes.............have fun. You can make any type of liquid soap your heart desires.
Step 7: This Concludes the 5 Principals to Master and Understand to Achieve Beautiful, Crystal Clear Liquid Soaps Every Time!
Liquid soap making, just isn't that hard! Once you understand the guiding principals that are essential to the process you can make it too, with ease.
1. Oil selection
2. Determining Lye Requirements
3. Cook time and temperature
4. Correct weighing and measurement of ingredients
5. Dilution rates
After searching the internet and reading the available books. I realize there is not a lot of information out there, related to liquid soap making. I hope to help remedy that with Liquid Soap Lady's website dedicated to the art of liquid soap making. I sincerely hope you find this case study helpful and informative. If you enjoyed the post and found it informative, I'd be appreciative of comments and shares.
Thanks for Reading!