Making Soap

Soap is used to wash many things such as dishes or clothes, and in all cases it acts in the same way. It works as something called a surfactant, which emulsifies oils and allows water to transport them. Historically,

soap

was made using a combination of rainwater, animal fats or vegetable oils, and ashes. Over thousands of years, the process was slowly refined and eventually it was discovered that the main ingredient in the ashes was base. For a long time, all

soap

was solid, and it wasn't until 1865 when a man named William Sheppard patented a liquid version. From then on, more and more liquid soaps were developed, and now we have a huge variety of different options.

The invention of a suitable form of liquid soap was actually a big deal, because it made cleaning things like floors and clothes much easier. Soap is derived from triglycerides, which are fat storage molecules used by almost all plants and animals. Animal fats and vegetable oils are almost pure triglycerides. There are two main parts of the triglyceride molecule: the glycerol backbone and the fatty acid tails. An ester bond connects the tails to the backbone and is a relatively sensitive bond. When triglycerides are treated with a strong base such as sodium hydroxide, they undergo a saponification reaction. This leads to cleavage of the ester bond and the formation of glycerol and fatty acid salts.

Desalted fatty acids are pretty much what soap is. One end has a strong charge separation that makes it polar, while the long tail of the carbon chain is nonpolar. The polar end is hydrophilic, which literally means water-loving, and the chain is lipophilic, which means fat-loving. In general, nonpolar molecules dissolve in nonpolar liquids such as oils, and polar molecules dissolve in polar liquids such as water. Because this molecule has both properties, it acts as a kind of bridge between oil and water. When soap is shaken with water, the molecules organize into spherical structures called micelles. The hydrophilic and polar heads are in contact with water on the outside and the non-polar tails are protected on the inside.

Micelles are technically not dissolved in water and exist as a colloid, which is a very finely dispersed suspension. If oil is present, the micelles can collect and retain a small droplet within their non-polar interior. The glues inside dissolve in the oil and the entire drop is protected from water. The polar heads give the surface a negative charge that helps repel other micelles. This prevents the oil from merging and keeps it separated in the form of very small, stabilized droplets. When it comes to

making

soap, it can be surprisingly complicated. It always involves basic hydrolysis of triglycerides, but the ingredients and process differ quite a bit.

Depending on the base used and the source of the triglycerides, the final soap can have very different properties. In fatty acids, the most important characteristic is the length of the chain. As the chain length increases, it becomes less polar and therefore less soluble in water. Long-chain fatty acid soaps also tend to be harsher and don't lather as easily. The base used will influence the fatty acid salt produced in the end. For example: with sodium hydroxide we obtain sodium salt fatty acids, which tend to be harder and less soluble. Potassium hydroxide forms much softer salts that are soluble in water, which is why it is the base used to make liquid soaps.

It's not as common, but lithium hydroxide can also be used to make lithium soap. However, this soap is not intended to clean things; It is usually dispersed in an oil to form a thick lubricating grease. It is non-corrosive, adheres well to metal, and is used to lubricate many household products. Soap can be made through two main processes: one cold and one hot. The hot one is done at about 90°C, and the cold one is close to room temperature. The main benefits of the cold process are that it is easily molded into many different shapes and is compatible with a wide range of additives.

The main disadvantage is that it typically takes four to six weeks to cure before it can be used. The benefit of the hot process is that it is quick and only takes about a day to cure. However, it is very thick and can only be molded into very basic shapes. Additionally, since it needs to be heated, many additives are not compatible. For this video, I have decided to cover both processes and will be

making

both solid and liquid soap. There's a lot to cover, so I've split it into two videos. For this one, I will make solid soap using the cold process; and in the second part, I will make liquid soap using the hot process.

Well, to make the solid soap, I will need three main things: olive oil, coconut oil, and sodium hydroxide. It is also possible to use other oils such as sunflower or almond, and the properties of the oil you choose will change the characteristics of the final soap. There are a few types of olive oils you can buy at the store, but when it comes to making soap, it doesn't really matter too much. On the right I have all the additives I plan to put in the soap. With cold process we can use a lot of different additives and I'm going to add things like lavender, cinnamon oil, and maple coffee.

One thing I want you to remember is that making soap is like cooking and there are many different things you can do. The recipe I'm following is just one of thousands, and if you decide to try it yourself, don't feel like you need to do exactly what I do. I highly recommend you do some searching online and find the recipe that best suits your needs. To start, I need to make a sodium hydroxide solution, so I measure out 200 milliliters of distilled water. I then weighed out about 80 grams of sodium hydroxide. Sodium hydroxide is a strong base, so you should be careful when working with it.

However, unlike what they showed in Fight Club, touching it won't melt your skin. If it comes into contact with your skin or hands, remove it quickly and, just in case, wash it with plenty of water. Anyway, now it's time to dissolve the sodium hydroxide, and this is where the real danger comes in. Unlike the solid form, a sodium hydroxide solution is much more corrosive. Additionally, dissolving sodium hydroxide generates a lot of heat and the solution will get quite hot. You might notice here that I'm not wearing gloves yet, and this is because the contact with your skin isn't that bad yet.

However, if you accidentally splashed some into your eyes, it could quickly cause significant damage and potentially blind you. So for this step, some type of eye protection such as glasses is absolutely mandatory. You can also wear something like a lab coat to protect your clothing if you're worried about damaging it. Just to show you that it's not the end of the world if it comes into contact with your skin, I purposely wet my finger. After doing this, I simply washed my hand with some water and felt absolutely no irritation or anything. Anyway, all the sodium hydroxide eventually dissolves, but the solution is still quite hot, so I temporarily set it aside to cool and prepare the oils in the meantime.

So for the olive oil, I need 500 grams and I weigh it with a kitchen scale. When I'm done I put it aside and move on to the coconut oil. The oil is solid, so I have to scoop it out with a spoon. When I finish weighing one hundred grams I put it in the microwave. The melting point of coconut oil is only slightly above room temperature, so it doesn't take much heat to completely melt it. The now liquid coconut oil is then mixed with the olive oil and stirred well. To the oil mixture I add the sodium hydroxide solution from before.

By the time it is added, we can already see some turbidity, which is the beginning of the reaction. With a spoon I give it a quick mix and then continue with a hand mixer. Before I start, I cover the top with some plastic wrap to try to prevent splatters. Anyway, if you are going to make soap using the cold process, I recommend investing in a hand mixer. I think this one only cost ten dollars or something. It's definitely possible to do it manually, but it takes a lot more time. Well, what we're happening here is known as a saponification reaction.

The ester bonds in the triglycerides of olive and coconut oil hydrolyze, forming salty fatty acids and glycerol. As for the mechanism, we start with an attack by the hydroxide ion that opens the carbonyl. Electrons from oxygen moved to reform the double bond and the carbon-oxygen bond between the fatty acid and glycerol is broken. The negative oxygen charge of glycerol picks up the acidic hydrogen from the fatty acid. This reaction is repeated two more times to completely separate the glycerol backbone. When making hard soaps, it is very important to use a little less sodium hydroxide than necessary to completely saponify all of the oil.

The sodium hydroxide is consumed in the reaction and we want little or nothing left at the end. Otherwise, it can sometimes be irritating to the skin. Plus, leaving a little extra oil in the soap will make it gentler on your hands and less dehydrating. This idea of ​​using more oil than necessary is generally known as supergreasing. Since this is all done cold, the reaction is quite slow, taking about two weeks to complete. It is then left for another four weeks for excess water to evaporate, which helps harden the soap. With very little mixing, it really doesn't take long to reach a stage called "trace." At the trace point, we have a stable emulsion and the oil will no longer separate.

However, the soap may still be quite thin at this point and if we continue to mix things up, it will thicken. There is no truly perfect thickness to go by, and it really just depends on the person making the soap. There are some people who like to stop when it is very thin and runny, and others like to continue until it is quite thick. From what I read, the point at which you stop doesn't really affect cure time or anything like that, and mostly affects design possibilities. The light stroke is very liquid and seems to be the best for making swirl designs.

It is also an ideal point to add liquid additives because they will mix very easily. The middle trace is good for adding solid things like poppy seeds or coffee grounds because it's still easy to mix, but they will remain suspended in it. The thick stroke is quite viscous and holds its shape when manipulated, so it's really good for making textured designs. It's also good if you want to make soap with multiple layers. Anyway, I'm not doing anything fancy and kept going until about a medium trail. I chose to get to this point because I need to mix liquid and solid additives, and I can do it all in one batch.

I wanted to make seven different types of soap, so I transferred almost everything to separate beakers. I tried putting the same amount in each, but clearly failed. To the first glass, I added cinnamon essential oil, which is practically pure cinnamaldehyde. Then, using my stirring rod, I mixed it as best as I could. One thing to point out is that I'm not an expert on this, and in each case I think I added too many things. When I was done, I quickly marked the glass with “cin” for cinnamaldehyde and then moved on to the next. For this one, I added bitter almond essential oil, which is pretty much just benzaldehyde.

Benzaldehyde has a very pleasant almond odor that smells like cherry candy. One of the main reasons additives are added after reaching trace is because, at this point, most of the sodium hydroxide has been consumed. Certain products, especially cinnamaldehyde and benzaldehyde, are quite sensitive to strong bases. If they had been added immediately at the beginning, much of it would have reacted with the sodium hydroxide and been destroyed. In the third I added freshly ground lavender. For the fourth I used a bunch of dark cocoa and the end result looked like a chocolate pudding. In the next one I decided to make a scrub, so I added some poppy seeds.

I felt like the poppy seeds alone might have been too simple, so I added a few drops of food coloring. I purposely didn't mix it completely, so I could get a slightly swirly color effect. For the sixth, I melted a bunch of menthol crystals and threw them all in. Menthol has a very strong mint smell and is the complete opposite of spicy. Instead of inducing heat, it induces the sensation of cold. For this batch, I added too much and it will probably hurt to use this soap. I thought since it's menthol, it would make sense for the soap to be green.

However, after mixing it for a while, it somehow turned orange. Anyway, for the last one I used maple coffee grounds. I mixed it well and then went back to the first one and added a bunch of red food coloring to make the cinnamon pink. Okay, now it's time to mold the soap. And you can buy one or make it yourselfsame. I decided to do it both ways and would just make a custom mold. Making this is pretty easy: I just mix an equal amount of each part and blend until it's a uniform color. I then squished it around the bottom of a beaker and included a 3D printed model of the caffeine molecule.

When the mold was ready, I took out the glass and took out the plastic molecule. Then, with some scissors I cleaned the edges and it's practically ready. By the time I started transferring things to the molds, it had already gotten much thicker. However, one thing to keep in mind is that each batch is not the same and this is because different additives can affect the thickness. So, for example, the first was cinnamaldehyde and although it was thick it still seemed a little liquid. Now with the benzaldehyde you can see that it is much thicker than the previous one and is almost like a paste.

Most of the others were relatively liquid, except for menthol, which was also a paste. Anyway, it was a little tricky, but I finally transferred everything to the mold. Using my finger, I wiped it off and then temporarily placed it aside. So now I added the coffee mold to the mold I made. Using the spoon, I push things down to make sure the molecule is completely filled. So at this point. I was almost done, but apparently I still had a little more soap left in the original container, so I filled another mold. For the third mold I did the same as with the first bar of soap: I just added cinnamaldehyde and a lot of red food coloring.

I left it out all night and by morning it had hardened quite a bit. So now that it's cured a little, it's time to unmold everything. At this point, all soaps are solid, but still relatively mild. While it is still soft, it is a good idea to shape things because it is very easy to cut. If you wait until it's completely healed, it will be a pretty big pain. When I unmolded the smaller cinnamon oil soaps, you can see that they weren't quite ready. As we just saw before, additives can affect thickness, so it's not surprising to see that it could also affect cure time.

And if you don't take this into account, you will end up unmolding the soap here like I did, and some will fall apart. Anyway, I went ahead and unmolded them all, and you can see that, for the most part, they were pretty good; There were only a couple of terrible ones. These were the last to be unmolded and were pretty easy. However, visually you can see that the cinnamaldehyde and menthol ones are much milder. Now I have to wait four to six weeks for all the soap to dry. All soap should be turned at least once a week to ensure it dries properly.

This is six weeks later, and at this point, the soap should already be ready. All of the pieces look pretty much the same, except they are definitely a lot harder than when I started. Now let's test the soap and see how well it works. I decided to go with the menthol because I wanted to see what cooling effect it would have on my hands. Based on the amount I put in, I expected it to burn a little, but I didn't feel anything at all. Apparently I made a decent bar of soap. Anyway, now that I've managed to make solid soap, I'll move on to the second part where I make the liquid version.

I highly recommend you watch it because, well, I mean, at least I think it's interesting. I also make it using the hot process, so you can see how it compares to the cold process. You can find it by clicking the link on the screen or in the description. I originally planned to keep all of the soap I made, but at the last second I decided to give most of it away. I'm going to do the same promotional thing that I did in a previous video, where all you need to do to participate is follow me on Twitter, visit my Instagram or subscribe to me on this YouTube channel or my other one.

NiloBlue channel. The link to the contest will be in the description and this time I will choose five winners, so the chances will be much greater. Each winner will receive a random bar of soap, not including the caffeine one because I want to keep it, or the menthol one because I used it. I will ship everything completely free and I will also ship it anywhere in the world. And just one last thing. The winner of my previous contest, Jou Young, never responded to my email and never contacted me. So, Jou Young, if you're listening to this, I'll give you another week to contact me either via Twitter or email.

Otherwise, I'll draw another winner. Thank you so much to all my Patreon followers - anyone who supports me will see my videos 24 hours before I post them on YouTube and will also be able to contact me directly. . Anyone who supports me with five dollars or more will also receive her name at the end of the video, as seen here. In the last shot of my video here, I want to start including music. I don't really want the typical royalty free stuff and prefer to support some artists with free advertising. So if you're interested, send me an email or hit me up on Twitter and if I like what I hear, I'll include it.