Ask Our Expert Soapmakers

Knowledgeable Answers to YOUR Questions!

Ask Our Expert Soapmakers

Do you have a soapmaking question? You’re not alone! Check here to see if your question has already been answered. And, if not, use our chat feature to contact our experts!

Hello… How can I wash the soap that I am making? And how dangerous is lye? – Phionah

Hi Phionah, that is a very important question. Lye can be deadly if it is ingested, and can cause burns on the skin, but that can be said about many substances. Knowing the correct ways to handle lye keeps you safe. Here is an excellent story about safety precautions when handling it. If you follow all the recommendations and keep the lye away from children and pets, you will be just fine.

As far as your other question, regarding how to wash the soap you’re making, I’m not sure I understand. Are you trying to remove a layer of soda ash that appeared on the top of the finished soap? – Marissa

Thank you for the help with lye, but in our chemistry lesson, a teacher told us that after forming a soap solution, sodium chloride is added to make the soap float. After that, the soap is washed and adding other ingredients like perfumes bleach, etc. Now I don’t even know how we separate soap from the cake. – Phionah

It sounds like you learned the chemical process of a commercial detergent versus homemade soap. One of the most preferred traits of home soapmaking is that people don’t have to learn the chemistry or even handle any of the chemicals other than lye. It relies on the simple act of mixing the alkali with the acid (oils and fats) to create a salt (finished soap), and adding in fragrances and colors as desired. It’s a completely different process. – Marissa

I would like to know, which colors do I add to soap? Is it OK to use food
– Phionah

Food coloring is not strong enough for soap, and the color often morphs from the alkalinity or the heat. If you are interested in coloring your soap, this tutorial on our site explores some of your best options. Good luck!

Hi, I am new to soap making. Where do they buy oils (olive oil, coconut oil, lard, and others)? Of course, all grocery stores are too expensive. Please advise. – Lisa

I am located in the United States, so the companies I can suggest from first-hand experience are limited to the ones that sell here. It is true that the larger the bulk, the less expensive the base price when it comes to oils. As a beginner, of course, you can always use what is easily available at your local store and save on shipping costs, but when you are ready to start purchasing in quantities of a gallon or more, it really does pay to use one of the many soap supply companies out there. One of my favorites is They have everything you need from oils to molds, fragrances, and colors, plus equipment and supplies for making lotions, scrubs, and many other bath and body goods. If you order $25 or more, shipping is free. is another good source for all things soap making. They sell their oils in bulk and also feature pre-mixed oils that only need lye and water added. Their oils come in bulk bags that can be frozen, boiled or microwaved for convenience. They are located in Washington state, so they are a good choice for shipping if you are on the west coast. Last, I would be remiss if I did not mention, one of my all-time favorites for a wide variety of fragrance oils to use in soap. They now sell fixed oils in bulk as well. Their quality is always top-notch, and their shipping times and rates can’t be beat. They are located on the East coast and so might be a better choice for those located over in that area. – Melanie

I want to ask you if mixing black soap and egg is good for black skin. – Idowu

While I have not been able to find any examples of this particular combination — congratulations, you’ve invented a new soap! — both African Black soap and egg soap are lovely for all skin tones. The rich shea butter in African Black soap is well-known for its emollient and soothing properties. The toning effects of egg whites in egg soap, and the rich proteins provided by the egg yolks, would certainly yield a soap with a unique set of virtues. If you decide to try mixing the two, please let me know how it goes! – Melanie

As a soapmaker starter, I wish know what percent of lye is required to make five ounces of shea butter soap. – Bambidele

If you are using ONLY 5 ounces of shea butter for your soap, you will need .61 oz of lye and at least 2 fluid ounces of water for a 5% superfat soap. Be aware, however, that a soap made with nothing but shea butter will not have the best features for a soap. It will be a very hard soap, but the lather will be poor. It is best, when making a soap, to use a mixture of oils to capture all of the best properties of each. Try adding some olive oil and coconut oil to your recipe for better results. A lye calculator is located at if you need help! – Melanie

I want to make soap using coconut oil 90% and castor 10%. Kindly help me with optimum superfat percentage. – India

Hi, that sounds like nice, sudsy soap. Since your coconut oil percentage is so high, I wouldn’t recommend going below 15% superfat. Probably 20% is going to be best, if you don’t want a bar that is drying. I’m curious why you want 10% castor oil, as coconut oil already provides a great lather and it’s usually not recommended that you exceed 5% castor oil. If you choose to use 10%, I would love to hear how it turns out and if the hardness of the coconut oil counteracts possible stickiness from the castor oil.

Here is a great story that details the properties of many oils used for soap: – Marissa

I’m trying to figure out how much lye water to add to frosting for soap cupcakes. Everything I’ve tried has failed. Please can you help me? – Rebecca

When making soap frosting, simply use your regular soap recipe and omit the fragrance, which can cause acceleration. Mix in the lye and water per the recipe instructions, there is no difference for frosting. Do not blend the soap batter to a medium or hard trace — a light trace is sufficient. Then set aside a portion of your soap batter for frosting, and continue with the rest of the batter as usual, adding fragrance and color and pouring into the molds. Then, you wait. Check the frosting portion every 5 minutes and give it a stir until the proper texture is achieved. Then fill your icing bag and have fun! The trick to frosting is to be patient and wait for the right texture, then work fast. – Melanie

I’ve tried twice to make sulfur soap. It worked once. I read somewhere online that adding sulfur during the trace phase changes it chemically by neutralizing the lye and can slow it down or stop the saponification process. Timing is everything. I’m thinking that’s the reason one batch worked and one never got hard. It was solid but soft. Since re-batching a batch of basic soap that has already gone through the process of saponification,  It sounds like this could be the way to add sulfur to the batch without changing it chemically. I make a simple tallow soap. – Bryan

Sulfur can be added at up to 1% of the total oil weight to your soap recipe. Add it to your base oils and blend well before adding lye and blending to light trace. Using any more than 1% sulfur can result in a brown, mushy mess instead of the soap you are expecting. If you want to add a slightly higher percentage of sulfur, you will need to use a Hot Process recipe and add the sulfur at the end of the cook. I am not aware of a chemical reaction between sulfur and lye at normal temperatures, however, it does produce sodium sulfate, sodium sulfide and water in a reaction that occurs at temperatures above 1,112 degrees Fahrenheit — not something that will be a problem in your soap. – Melanie

Commercial sulfur soap claim 10%. How do they do that? What’s 1% of 3#? Thanks for the response. – Bryan

Commercial soap is usually not actually soap — it is a combination of surfactants that are pulverized and mixed with active ingredients and then compressed to form bars. Thus a higher level of powdered Sulphur can be used before compression is compromised.

1% of 48 ounces is 4.8 ounces, if by 3 lbs. you are referring only to oil weight. Always measure by oil weight. – Melanie

Does the 1% hold true with a rebatch? – Bryan

Yes, because the issue with the sulfur is that it is a powder, absorbing water, and taking up space in the soap’s structure. – Melanie

I like to know what’s the benefits of use cinnamon in m&p soap making? – Atu

Use of cinnamon in melt and pour soap is going to be purely for aesthetic reasons. For instance: if you would like a nice cinnamon-brown color in your soap but don’t want to resort to dyes or pigments. If you made oatmeal soap using a melt and pour base, you may want to sprinkle a little cinnamon in the mold before pouring, so the finished soap resembles a baked good. There is a small chance some cinnamon fragrance would present in the soap, but it wouldn’t be much.
Cinnamon bark oil HAS been shown to have antimicrobial effects against certain drug-resistant bacterial strains. However, the use of cinnamon oil is highly irritant to the skin when used full-strength, and to achieve a concentration high enough to harness these antimicrobial properties, your soap would cause more problems than do any good. Scientists who studied these effects recommend diluting cinnamon oil at NO HIGHER than one drop per 30-40mL of carrier liquid if you’re going to use it on skin or hair. If you want a cinnamon fragrance in soap, and don’t want any other fragrances (essential oils) that can dilute cinnamon bark oil and its potential to cause contact dermatitis, I recommend choosing a fragrance oil blend from a reputable soap supply company. – Marissa

Hi there! I just made an essential oil soap and I accidentally added too much essential oil to it (double the required quantity) will that be a problem? – Sara

Hello Sara, the answer is yes — this may very well be a problem. Every essential oil has a Safe Usage Rate to be followed, whether you are making soap or lotion or other bath and body products. The Safe Usage Rate is a very important set of guidelines that can protect you and those using your soaps from skin sensitivities, irritations, or even chemical burns from too much essential oil. To save this batch, I would recommend shredding down the soap and mixing with an equal amount of fresh, unscented soap batter to dilute the overall scent load. The shredded soap will also give a lovely confetti effect to the finished soap. In the future, Safe Usage Rate Calculators can be easily found online and will help you to keep your soaps safe, no matter which essential oils you are using. – Melanie

Hi, how many ml of essential oil per 500g of melt and pour soap? – Will

Essential oils, every single one of them, have a different recommended usage rate to be safe on the skin. In soap making, we measure essential oils either in ounces or in grams. To determine how much of a specific essential oil to use in 500 grams of melt and pour soap base, you will need to look up the Recommended Usage Rate of the essential oil in a melt and pour soap base. Reputable soap making companies provide this information readily on their sites, or you can look it up (simply Google “Safe Usage Rate” and the name of the essential oil) for each essential oil. To calculate the usage rate, take the recommended percentage for melt and pour and divide that amount by the amount of soap being used. For example, if you have a .5% usage rate for melt and pour, you would divide 500 grams of melt and pour by .5 grams of essential oil, which gives you 10.0 grams. These usage rates are approximate, so you can round up or down as necessary. – Melanie

Can you tell me the purpose of the sodium lactate in your goat’s milk lotion recipe? What does it bring to the recipe? – Jannalynn

It’s a humectant that draws moisture toward the skin, so the oils actually soak in and benefit the skin instead of just staying on top. This reduces the greasy feeling, as well. – Marissa

Is it possible to add methyl salicylate to before the saponification process to make salicylic acid? What I really want to know is, is there a way to make soap so that the end product has some salicylic acid? – Joshua

The simple answer is this: You can add salicylic acid to soap, and it may lower the pH of the soap to a gentler level for the skin, but the chemical reaction between salicylic acid and sodium hydroxide will produce sodium salicylate, a Nonsteroidal Anti-Inflammatory drug that is not absorbed by the skin. Salicylic acid in big enough quantities to remain unchanged in the finished soap would yield a rubbery soap with no lather. The best applications for getting salicylic acid into your skin is by way of a lotion, peel or toner. – Melanie

Hi. I am Kaneez Fathima. I tried the tomato leaf soap. I followed every step from the recipe given. It’s three days and my soap looks good and hard from the top. But is still not set at the bottom of the mold. How long does it take to harden so I can remove it from the mold?

The soap looks lovely, nice swirl pattern on top! It looks like, from the level of fullness in the mold, that you didn’t accidentally double any ingredients or anything obvious like that. Sometimes soaps just take a little longer to set up. Is the bottom of the soap soft or completely liquid underneath? If the soap is simply soft, I recommend placing it in the freezer until solid, then turning it out onto waxed paper to air out for a few days. That should solidify things well. This particular batch of soap may end up being a little slow to harden up, but by six weeks of curing it should be similar to others. 

However, if the soap underneath is truly liquid and not set at all, that would indicate separation of the contents. That might be caused by not coming to a full enough trace. It can also possibly be caused by the particular fragrance oil you have used. Whenever buying a fragrance oil for the first time, I definitely recommend reading the comments from other users to see if anyone has had problems with a fragrance oil in cold process soap. 

But if the soap is indeed separated in the mold, never fear – hot process can fix the mess and turn it into usable soap. Simply turn out the contents of the mold into a crockpot set on Low and process, stirring occasionally, until the mixture is fully incorporated and thick like oatmeal or mashed potatoes. Test it to make sure the lye is finished working, either with a pH testing strip or with the tongue-touch “zap” test. If the lye is done, pour into the mold and allow to set. It should be very firm within 24 hours and easy to turn out and slice. – Melanie

Hi for making shampoo bars, what can be the alternative to beer how much is to be used? – Keneez

You can use water, ounce for ounce, as a replacement for the beer. Many other liquids could also be used the same way, but you have to consider the amounts of sugar, sodium, and carbonation present in your chosen liquids. Therefore, if there is a specific liquid you wish to use besides plain water, we will have to consider it individually. – Melanie

Does the recipe for foaming bath butter also require curing time and how long is its expected shelf life? Thank you. – Ja

No, it does not require curing time. The soap is fully saponified, and because it is not being used in bar form on the skin, there is no need to wait for the soap to become milder and for the water to dry out. The foaming bath butter has extra oil added to make it milder and more gentle to the skin immediately. – Melanie

Is mixing black soap and egg good for black skin? – Idowu Ridwan

While I have not been able to find any examples of this particular combination – congratulations, you’ve invented a new soap! Both African Black soap and egg soap are lovely for all skin tones. The rich shea butter in African Black soap is well-known for it’s emollient and soothing properties. The toning effects of egg whites in egg soap, and the rich proteins provided by the egg yolks would certainly yield a soap with a unique set of virtues. If you decide to try mixing the two, please let me know how it goes! 

Does this work? I said it’s good for all skin TONES, not all skin TYPES – because some people find shea butter clogs pores or are irritated by the natural latex content. -Melanie

I would like to know the use of fresh fruits in soaps hot process. – Nisa

“Using fruit puree in hot process soap is as easy as working with a water discount. Simply use one ounce of fruit per pound of base oils as your maximum usage rate, and subtract that amount of water from your recommended water amount. For example, if your recipe is two pounds of base oils, 10 ounces of water and 4.5 ounces of lye, you would use two full ounces of fruit puree, and subtract that 2 ounces from the 10 ounces of water used to hydrate the lye. Add your fruit puree after the cook and during the cool-down period before pouring into the mold. Although the soap is no longer caustic once cooked by hot process, it is still a high enough ph level to preserve the fruit puree in the form of finished soap. One last tip – be sure that your fruit puree is totally blended, without chunks or small bits which can go rancid in finished soap. Use a sieve if necessary to achieve a smooth puree.” – Melanie Teegarden

Is mustard oil safe to use in soapmaking? It is from India and I bought it in Hong Kong. Thanks. – Raja

There are two products that are referred to as mustard oil. The first is a cold-pressed oil that is extracted from the seeds. The second is an essential oil derived from distilling the crushed seeds with water. Only the cold-pressed oil can be used in soap making, and only with an abundance of caution: mustard oil can be a strong skin irritant. These soaps should never be used on the face or any part of the body with mucous membranes because it can be too harsh. As a hand and foot wash, soap enriched with up to one-half ounce of mustard oil per pound of base oils can be used. Mustard essential oil should never be used in any quantity because it contains natural cyanide products that are a powerful poison. Avoid mustard essential oil completely. – Thanks, Melanie Teegarden

16 thoughts on “Ask Our Expert Soapmakers”
  1. I’ve seen recipes for homemade Castille soap, but retail Castille soap also comes in liquid form. Is it possible to homemake liquid Castille used in many DIY recipes? What do you do differently? (Not to make bars and grate them into water)

    1. Hi Cindy, I know which soap you are talking about, and if you read the label, you will learn that “Castile soap” can have a very broad definition and is starting to lose its actual identity as a pure olive-oil soap from Spain. One huge difference between liquid and solid soaps is that the liquid version usually uses potassium hydroxide while the solid version uses sodium hydroxide. I know many soapmakers who go through the extra labor to make a liquid soap such as this, especially one that’s clear, but they tend to be few and far between.

  2. Hi, I was wondering if you have to wrap up the shampoo bar soap after putting in the mould to keep it warm, since you have said it gets very hot? I want to try this out soon if I can x

    1. Hi Camilla, that may depend on the temperature of your own workspace. Since it gets so hot, you most often would NOT have to insulate it, unless you make soap in a cold shop or garage. Watch the soap as it gels; if oil pools on the top, it’s too hot.

  3. I found a recipe for 100% coconut oil soap (3 lbs) that calls for 4oz cinnamon essential oil? Is this a typo?? I am nervous to try it, but really want to.

    1. I would also be nervous to try it! Both cinnamon bark and cinnamon leaf essential oils can cause contact dermatitis in even small amounts. Reputable soap supply sites, like Brambleberry, instruct that cinnamon leaf essential oil should not be used at more than 1% of the recipe for wash-off products like soap, and should never be used in stay-on products like lotion. Since 3 pounds of coconut oil is 48oz, that 4oz of cinnamon oil is less than 10% of the recipe, but I still would not recommend this recipe for sensitive skin. Another important factor in this recipe would be the superfat percentage. If this recipe calculates at less than 20% superfat, a 100% coconut oil soap would be too drying, and that cinnamon oil would be especially irritating. Another option might be to purchase a pre-mixed cinnamon-scented fragrance oil specially formulated for soap. That way, you get the cinnamon fragrance but don’t have to worry about dermatitis from the oils.

  4. Very new to soap making, do you have to do use many different kinds of oil or you can use only one kind of oil like just shea butter?

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