Dr. Kevin Dunn, Professor of Chemistry at Hampden-Sydney College and author of “Scientific Soaping” and “Caveman Chemistry”, presents the “Secret Life of Soap”, in which we learn the chemistry involved in the conversion of oil and lye into soap. His presentation includes lessons on what actually occurs during saponification at the molecular level, and answers questions that many soapers don’t even know they have. Dr. Dunn dispels myths and wives tales and gives you permission to experiment with other tactics. Temperature, water volume and gel phase are scientifically analyzed, and an important distinction is made about why nerds and cheerleaders don’t sit together in the lunchroom. If you never loved science in school, Dr. Dunn will change your perspective and make learning soap chemistry an adventure.
KD – Normally I would introduce myself and tell you something about myself, funny stories, but I know that I’m on a clock. Well while that’s going on I’ll tell you a funny story. Derek was right, the whole thing started with the idea of walking naked into the woods. And we were going to take people into the woods and we would make everything from scratch. So we would make fire from fire, we would make pottery with clay. So I developed this course “Caveman Chemistry” with that notion of starting at the beginning and building up the history of chemical technology one project at a time. And one of the projects was soap. So Cavemen Chemistry was kind of the course that I’m famous for, and in 2005, Jackie Thompson from the Handcrafted Soap Maker’s Guild, asked me to speak at their convention. And I said, “What do you want?” and they said “We want you to speak for 90 minutes about the chemistry of soap.” I said, “I don’t think you know what you’re asking for. I know that I can talk for 90 minutes about the chemistry of soap but I’m pretty sure your people don’t want to listen to 90 minutes of the chemistry of soap.” But, “Oh yeah, that’s what we want.” So that’s what I did and, not only did they listen for 90 minutes, they canceled their break and kept me another 20 minutes with questions. So um, that’s how I got into soap; Derek said I have all the answers and I want to step back from that. When I started, I thought I understood soap and every time somebody asks me a question, I get all kinds of new questions I never thought of before. It’s still an exploration for me. And so, one thing, if you think about the kind of scientist you might see on TV, the scientist says, “That’s impossible.” I never say that. I always say, “Well, that would surprise me.” If somebody says, “Oh I think you can make soap without lye.” Well, that would surprise me. And I’ve been surprised a lot. But nevertheless, when I say “That would surprise me,” it really would surprise me. So I’m never going to tell you that you can’t do something or it can’t be done. And the thing that I live for is those surprises. I love to be wrong, because if I’m wrong, that means that I now understand something that I didn’t understand before. This surprises me too! So, I’m going to go ahead and get started without the slides because there’s a parable I can tell you. I’m going to be talking about molecules. I don’t want you to be frightened. For some of you, it might look kind of terrifying and I’m going to be here all weekend to answer questions, and in addition to that, if you additional questions, you can email me at ****. You need to include the word “soap” in the subject line. If the word “soap” appears in the subject line, it goes into a special folder that separates it out from the Nigerian widows who are constantly pestering me to launder money for them. ******* So I’m going to tell you the parable of nerds and cheerleaders. Everywhere in the United States, in high school cafeterias, there is a pattern that is in place. You will see tables where the cheerleaders sit, and you will see the tables where the nerds sit. And the nerds are never sitting with the cheerleaders and the cheerleaders are never sitting with the nerds, and why in the world would that be the case? Some people would say it’s because nerds hate cheerleaders. Not the case. I was a nerd, maybe I am a nerd, and I can tell you cheerleaders are awesome. You might think that the cheerleaders hate the nerds and that’s also not true. Because I knew cheerleaders in high school and you know, we were perfectly friendly. Nevertheless, I never sat at the cheerleader table. So you wonder, why is that? Why would that be the case? All that’s necessary is that the cheerleaders like other cheerleader MORE than they like nerds. It isn’t necessary that they hate the nerds. They just have to like the cheerleaders more than they like the nerds. And that means whenever there’s an empty seat with the cheerleaders, there’s nothing stopping a nerd from coming and sitting down. But if he does, every cheerleader at the table is thinking “could have been another cheerleader sitting there”. And so what happens is that the cheerleaders tend to congregate. Now what about the nerds? Why do the nerds sit together? No place left to sit. So, that’s what’s going to happen with molecules. I’m going to talk about two kinds of molecules, polar molecules and non-polar molecules. All chemistry is driven by electrical charges. Molecules can be positively charged, negatively charged or not charged; and as you know, opposites attract. Positive charges attract negative charges, negative charges attract positive charges, and that’s what makes the world go round. So I’m going to talk about non-polar molecules and polar molecules. Polar molecules have charges, typically they’ll have a positive charge and a negative charge. The two charges attract one another. So I do want to touch on the acknowledgements. It’s the Secret Life of Soap – and I’m on the acknowledgements page. There are people, I can’t do all this myself. I go to soap conferences and people ask me questions and I don’t know the answers and that’s what drives me. I go home and I think, “How can I figure out the answer to that question?” I don’t have enough time to do all the lab work for that and so I have students who work for me every semester, doing the grunt work of the ideas that I’ve put together to answer questions. The things I’m going to talk about today, Mike Lawson at Columbus Foods – you might know them as SoapersChoice.com – years ago when I first started lecturing, I said, and we got our oils from SoapersChoice, and he has donated all of our oils ever since. So, um, I want to give a recognition to him. I want to recognize Derek for putting this weekend together and all the work that he does for you. Hampton Sydney College has allowed me to be a nut, for twenty-eight years, and I really appreciate that. And the students that did the actual grunt work on the things I’m going to talk about. John Campbell did the phase diagram work, Avery Moncure did the microscopy we’re going to look at, Andrew Bassinger and Tyler Bowman did the temperature profiles. In addition we had some X-ray diffraction work done; we don’t have an X-ray diffractometer and so we had an alumnus at Proctor & Gamble and he roped some of his people into working on the project for us. So Jody Akin and his coworkers I also want to acknowledge. So let’s look at the chemistry at the top of the next page. Oil and water. Oil and water don’t mix, you all know that. When you mix oil and water, the oil floats to the top and the water falls to the bottom. I have color-coded these molecules. The molecule at the top is an oil molecule, we use the word oil in two ways. We use oil to describe petroleum, and we use oil to describe animal and vegetable oil. The molecule here is a petroleum kind of oil molecule. I want to get started that even though we don’t use that kind of oil in soap making, it’s still that kind of oil that we’re trying to wash off, and the chemistry of it is very similar. I’ve color-coded this molecule green, it’s a non-polar molecule. It doesn’t have a positive end or a negative end, it’s uncharged along its whole length. And you don’t have to understand the details of the chemical structure, I just want you to recognize that that green molecule is non-polar, and non-polar things tend to be oily or greasy. So we can remember green and greasy, any green molecule actually is going to be greasy. At the bottom I have two water molecules. A water molecule is a much smaller molecule and it’s peculiar in that it has a positive and a negative charge. The oxygen atom is red colored for negative and the hydrogren atoms are colored white for positive. So, if you can think whenever you see a red and white molecule in this presentation, you’re thinking the red end is attracted to white and the white is attracted to , and how about the green? Not so much attracted because the green goes wherever there’s anyplace left to sit. So you can see I’ve drawn two water molecules here and they’re not randomly oriented, they’re oriented in such a way that the white atoms in one molecule are trying to get as close as possible to the red part of the adjoining molecule. This in the middle is our kind of oil. This is an animal or vegetable fat and it isn’t as simple as the petroleum oil, but if you look at its color, what color is it? It’s green so it’s . Greasy – it’s a green greasy molecule. If you look I’ve also drawn three other molecules. And what color are they . Red means . Negative, red is negative. There’s no white attached to them, there’s a hydrogen atom there, that little tiny molecule is a hydroxide ion, why is that important to us? Because we use Sodium Hydroxide to make soap. So here’s an oil molecule with three hydroxide ions hanging around it. And if you look at the, uh, you said this is a green oil molecule, but if you look in the center, you’ll see something. . How many? Three white atoms. Those are positively charged carbon atoms down in the core and now, if we think what’s going to happen here? We’ve got this situation going on – what’s going to be attracted to what? Red’s going to be attracted to the white. And I’ve drawn three of them because there are three carbon atoms in the center of the molecule. Next slide Doink! That’s what’s just happened now. The reaction has started, how many hydroxides do I have now? Hydroxides are – that’s one of them and that’s one of them. One of them went the wrong way, where did it go? It’s now right there – it’s stuck onto the carbon atom. You can imagine this molecule used to look like a knuckle with three fingers and we’ve just amputated a finger. This little guy right here, looking like a caterpillar with big red eyes, that’s a soap molecule. And if you look at its structure, what’s it look like? At this end it looks greasy, at this end it looks like water –we’ll say it’s watery. So one end of the molecule is greasy, the other end of the molecule is watery. Still got two hydroxide ions left and we’ve got this guy here. So what we had before with the three fingers attached is a triacylglyceride. There’s a big long word for you to have fun with. Triacylglyceride just tells you three, acyl is an acid group, and the glycerol is the knuckle that’s down the side. We started with the triacylglyceride, we’ve now got a soap molecule. And what are we going to call this guy? It’s not an oil molecule anymore. I’m going to call it – how about a diacylglyceride, because it’s still got two fingers left. What’s going to happen next? We’ve still got two hydroxide ions left, where are they going to go? To the white atoms. Now you can say as we advance the slide – dink! And there it goes. Another finger just fell off. One of these red atoms is what used to be left of the hydroxide ion and now we have two soap molecules and we still have a piece left, I wonder what we could call it. Monoacylglyceride. From now on, when you look at products and you see the list of ingredients – have you ever seen diglycerides, those two names mono and digylcerides? All it means is oil that hasn’t quite turned into soap. And that’s what’s left. We’ve got a monoacylglyceride. We’ve got one more step to go – dink! And there it went. Three fingers have now fallen off. We’ve got three angry red caterpillars and soap, soap, soap – and the thing left down in the middle that they used to be attached to . Glycerin. People ask me what’s the difference in glycerin and glycerol. No difference, it’s a synonym. Glycerin is the older name and when people discovered that – If you look at it, what kind of a molecule is this? Is it polar or non-polar? It’s polar, because, look, it’s got a red atom and a white atom, in fact it’s got three of them. So if water gets around this guy, what’s going to happen? Is it looking at a cheerleader or is it looking at a nerd? Looking at another cheerleader. So it’s going to be attracted to water, and if you look at these guys – one end of the molecule is not attracted to water, the other end is attracted to water – that’s what makes soap work. It’s like, uh, it’s like a Siamese twin. One twin is a nerd and the other is a cheerleader. So when it comes time to sit down, this is a molecule that can sit down at either table. Next slide. So, this is what happens when you have water in the vicinity of a molecule like soap. The water is going to be attracted to the two red atoms, we’ve got two red atoms and a white atoms, looks like a giant water molecule to another water molecule. Water is going to be attracted to one end and not attracted to another end. Down in the center of this guy there’s a white atom without any red attached to him. Remember we had hydroxide ions before? What do you use to make soap? Sodium hydroxide. Where’s the sodium? Well, that’s it. That white atom in the center there – that’s the captain of the football team. That’s the sodium ion that’s left over from the sodium hydroxide and being positively charged he is surrounded by a harem of nice luscious water molecule cheerleaders. Okay, next slide. Alright, I’m going to talk about an oil “Delight”. It’s in your book, Duckbar’s Delight is what I call this oil. Whenever we, in my lab need a good all-purpose four oil blend, this is what we use. I’m not saying this is the best oil blend, I’m not saying it’s the only oil blend. I’m just saying it’s the one that we use. An important piece of advice that I can give you is, when you’re doing an experiment, you want to change only one thing at a time. So, when we need a four oil soap, this is the one we always choose because we don’t want to be fooled if we were to choose a different four oil blend. We wouldn’t then know whether what had changed was because we used a different oil blend or because we had changed something else. So this is 39% olive oil, 28% palm oil, 28% coconut oil and 5% castor oil. I’m going to talk in parts per thousand. You all know what percent is, right? Percent means parts per hundred. Parts per thousand just gives us one more digit of precision, so a thousand parts of Delight has 390 parts of olive, 280 parts of palm, 280 parts of coconut and 50 parts of castor. You can always convert that to percent just by moving the decimal place one place over. Next. When I talk about lye, people use words synonymously but I’m going to be very precise. I can talk about sodium hydroxide, that’s a chemical name. I can talk about the white stuff in the bottle there, which may be mostly sodium hydroxide, I’m going to call that caustic soda. And I can talk about a solution of sodium hydroxide and water, and when I talk about lye, I’m always talking about the solution. We always make our lye the same way – we make it up exactly 50%. Soapmakers are appalled by that – 50% holy crap! That’s gotta be really dangerous. You know what, 30% is also really dangerous. 50% really isn’t any more dangerous than that. And we use 50% because we can always add more water. We can’t add less water. We can’t subtract water from the lye we’ve already made up so we make up 50% lye and that makes the math really easy. I want to weigh out three ounces of sodium hydroxide, how much lye do I need? I need three ounces of sodium hydroxide, remember I’m using my words very carefully. I need six ounces of lye. The math becomes very easy that way. And if I want it to be more dilute, I’m just going to add some more water. So, we would use 288 parts of lye to 1000 parts of Delight. The saponification value is 151 parts per thousand. In that 288, let’s call it grams, are you afraid of grams? Say 288 grams of lye, how much sodium hydroxide is there? 144, the math is easy, right? The saponification value is 150. So what does that mean? I’ve used more or less lye than I needed? I’ve used less. I’ve applied a discount here. Next slide. If you do the math, that turns into a 4.5% discount. I don’t want to hear that Dr. Dunn says, and by the way, I’m Kevin, you don’t have to call me, we don’t have to be formal here. Um, I don’t want to hear that Dr. Dunn says you ought to use a 4.5% discount. No, I’m just saying, in the work that we did, that’s what we did. And that’s what I’m reporting to you. Next. So, that means if I use 50/50 lye, 50%, next slide, now I can make soap lots of different ways. I can use 1000 parts of Delight to 288 parts of lye, and I can have 0 extra water. That’s as if I used 50% sodium hydroxide in my soap. I can also use exactly the same amount of oil and lye, but I can add 72 parts extra water, or 144 parts extra water, or 288 parts extra water. I have a lot of flexibility now to add more water or less water depending on what I’m trying to accomplish in my soap making. Next. If you calculate from those formulas, you can determine, the first one is 11% water and the one at the bottom is 27% water. I don’t want to keep talking about parts per thousand and percent so I’m going to use some shorthand now. Next slide. I’m just going to refer to low water soap, medium water soap, and high water soap. Low water soap uses 50% lye, high water soap used 50% lye and then added an equal amount of extra water to get a different formula. Next. So I asked, what is the correct amount of water to use? There is a correct amount of lye to use. We talked about a saponification value, there is an amount that is just right. Remember there were three hydroxide ions to each oil molecule. There is a correct amount of sodium hydroxide needed to turn oil into soap. The same thing is not true of water. Let’s look at it historically. Next. Ann Bramson, anybody know this book – Soap: Making It, Enjoying It. I think this started off, I’m not aware of an earlier book for people like you. Lots of books for people in chemical industry, lots of books for people at Proctor & Gamble. I think this was the first book for people like you – wanting to make soap. She used between 25 and 27% in her lye solution and the average was 26%. Next. Susan Cavitch, in 1977 wrote The Soapmaker’s Companion, anybody know this book? If you look at her formulas, they average 27%. Next. Essentially Soap by Robert McDaniel in 2000, he’s using 34%. Next. And Anne Watson in 2007, her average is 33%. So if you look at the trend, it seems that soapmakers are tending toward, they started out with a high water soap and they moved toward a medium water soap. I want to give you permission to explore low water soaps. I don’t want to hear that Dr. Dunn says you ought to make low water soap. I just don’t want you to be afraid to try making low water soaps. Next. Alright, I’m also going to talk about temperature. And you guys, if I say centigrade, is that terrifying to you? . Alright, so that’s okay. I give you permission to be terrified, but as a scientist, we always work in centigrade, that’s the way my mind is attuned. So I’m going to talk about 40⁰C, 60⁰C, and 80⁰C. Next. You can think of it as about 100⁰F, 140 or 176, and we will apply shorthand to that. I’m just going to call it cold, warm or hot, when I use those terms these are the temperatures I’m referring to. Alright, so what did we do? We took 100g of oil, we added however much extra water that we wanted and we added our lye into a 500mL plastic bottle. We’re making soap on a small scale. I tell people that I make soap one bar at a time and it’s always bad soap. It’s screwed up in some peculiar way to answer the question that I’m interested in. So we have racks and racks of single bar soaps, every bar on the rack is different; every one of them has a batch code, and we will monitor their properties over time to answer a particular question. So we needed a way that we could make one bar and do it reliably to get the same result every time. Instead of using a stick blender – how much oil is 100g? It’s like, you know, the bottom of your coffee cup, it’s like that deep in your coffee cup. Try using a stick blender on that. So we’re not doing that. We put everything into a plastic bottle and we just shake it up. We shake it up and then eventually the sound starts to change and then we’ve reached trace. And we pour it into, we use literally a coffee cup as an experimental mold, put a coffee cup lid on it and I’ve got an insulated soap mold for a single bar of soap. That’s what we’ve done. We put the plastic bottle on a paint shake for 15 seconds, I’m not telling you, you ought to do that. Why do we do that? We don’t want to be fooled – I don’t want one student who shook it for 15 seconds and another who shook it for 30 seconds. I don’t want one student that shook it hard and another that shook it easy. I want it to be that the shaking is the same every time so I don’t get fooled by different people shaking it different ways. We swirled it to trace and poured it into a mess of Styrofoam cups and they recorded the temperature every fifteen minutes for four hours. That’s what the students are for. I don’t want to do that part. Next. So I’m also going to use the word “phase” and phase means something very specific to a chemist. If I’m talking about water, water comes in three phases. You got ice, you got water, and you got steam. That’s an example of what I mean by phases. Next. It’s not the only one. I can talk about ice and cream and I can talk about ice cream. Those are three different phases of that system. Next. I can talk about gel and sol. You guys make Jello? How do you make Jello? You add hot water. Okay, if you add cold water, then what? It’s in the sol phase, if you heat it up then it turns into the gel phase. Two different phases of the same system. Next. We can talk about sugar and water and honey. What is honey? It’s a mixture of sugar and water and it’s a separate phase from either sugar, which is solid and white, or water, which is clear and runny. Next. We can talk about, do you guys make gravy? You mix flour and water, and then what? You mix flour and water and then what’s it like. It’s just pasty, it’s not appetizing at all. But put it in a skillet on the stove and it turns into something different. It turns into a different phase we call gravy. Next. I’m sorry. Soap is far more complicated. Next. Oh my god. I give you permission to be frightened by this diagram. It’s very complicated. Each one of these little regions is a separate phase of soap, and I don’t even know how many are up there. It’s something like a dozen. Good news for us is we don’t work over the whole range. This is percent soap, going from 100%, that means dry anhydrous soap, to 0%, that means just water. So this is soap and water, 100% soap, 100% water and anywhere in between. This is temperature, sorry it’s in centigrade. There’s 50, there’s 100, that’s like 200⁰F and that’s like 100 And where do we live when you’re doing the dishes? Do we live at the high soap end or the high water end? High water end. So when you’re washing dishes, you’re over here and how high up are you? The water coming out of your tap is like, 120, that puts us up here. This huge region is just dishwater. But that’s not where we live. Next. This is where we live. When we’re making soap, we’re down here at like 10% water, remember the percentages water we talked about, and we’re talking between 40⁰ and 180⁰, we’re talking in this red area, and in that red area there are two main phases of soap. One of them is solid, and the other is, the soap makers at Proctor & Gamble call this “neat soap”, but you guys know it by the name “gel”. Or you know, anybody ever talked about gel phase? Describe that for me, some people may not know what are you talking about when you say that? . Yeah. It looks like, correct me, it looks like Vaseline, right? It goes from being solid and white and you stick your finger and it’s hard, to being soft and mushy and it doesn’t separate. It’s not clear like dishwater and it’s very thick but not as hard as regular soap. So, we’ve got two different phases there – the Proctor & Gamble people call it neat soap and the handcrafters generally call this a gel phase. And there’s lots of discussion, anybody want to find out what that’s all about? Yeah, I’m glad, so you’re curious about it. That’s what I need, I need you to be interested, otherwise you’re just slogging through a boring chemistry lesson. Should you do it – shouldn’t you do it? Can you do it – can’t you do it? That’s what I’m going to be talking about. Okay, next. This is, so the previous diagram was from a journal article in chemical literature. This is a diagram that we generated using differential scanning calorimetry, which you don’t need to know about; and X-ray diffraction, you don’t need to know about. But remember, these are our soaps, this Aq₀ is what – low water soap, and this is the high water soap, and we’re going anywhere from 40⁰ to 200⁰F. And this is kind of a close up on that larger diagram – now this is not a generic soap, this is specifically for our Delight oil that I talked about. And these are actual experimental data that we recovered from actually making soap, shipping it off to Proctor & Gamble, they put it into expensive machines and sent us the results back and we tried to make sense of those results. At the bottom, this is solid soap. At the top, this is the gel phase, the Vaseline jelly looking stuff, and in the middle you have a two-phase region where you can have a mixture of both of them in equilibrium with each other at the same time. Next. Alright, I’m going to teach you some words and these are fun words you can use to baffle your friends, you’ll sound like a genius. So what is Neat Soap? It’s a lamellar lyotrophic liquid crystalline phase of soap and water. I’m going to teach you what each of those words mean and you can practice all weekend. Lamellar, say it with me, lamellar. Lamellar lyotrophic liquid crystalline phase of soap and water. Okay, next. Liquid crystalline, the molecules are free to move, what’s the difference between a solid and a liquid, molecularly? In a solid, the molecules are kind of close together and they’re locked in place, they can vibrate but they can’t really move around. In a liquid, molecules, they’re still close together but they slide past one another. And in gas, they’re far apart and they’re bouncing off the walls like a teenager on a sugar rush. So, I’m talking about something liquid crystalline, what does that mean? Liquid means the molecules can flow past one another but crystalline means they aren’t randomly oriented. They’re oriented in very specific ways. Any you know the word liquid crystal, you probably have some liquid crystals on your person right now. Look at your cell phones. The displays are all liquid crystal displays and there’s an electrical charge which orients the molecules one way when it’s on or orients it another way and they change colors depending on which way the molecules are oriented. So, this neat soap we’re talking about is a liquid crystalline phase. Next. Lyotrophic means there’s at least two kinds of molecules and the properties depend on the concentration. In your cell phones, the property depends on the electrical charge. In soap, it depends on the concentration. Now what’s in the soap? It’s soap and . The lye has already been used to make up the soap, so it’s soap and water. Glycerin is in there too, very good, so there’s actually three things in our soap. Lyotrophic means there’s at least two kinds of molecules and the properties depend on the concentration. So low water soap is going to be a different property from the high water soap. Next. Lamellar means the molecules are arranged in sheets. There’s lots of ways for molecules to line up. So in this lamellar phase, the molecules are arranged in sheets. Next. So this is what’s going on. We’re going to build this up. Can you make that a little bigger? Maybe not, I don’t want to screw it up. You’ve got the pictures there in your handouts as well, but you can see, this is just the little soap molecule that I drew earlier with the red eyes at the top, the water molecules are up there, and there’s a sodium ion in the middle. You’ve got the red eyes at the top and the green, greasy stuff at the bottom. If two soap molecules get together, how are they going to align? They’ll align two ways. The two watery ends will be attracted to one another and the two greasy ends will also be attracted to one another. So what we see here are two soap molecules lined up so that their greasy parts are close to each other. I have two more of them next door and next door and next door to get a whole row of soap molecules lined up tail to tail. Next. That’s what happens if I build it out in the third direction, we now have a watery layer and a greasy layer and another watery layer. And one more time and there it is. That’s what neat soap looks like on a molecular scale. All that’s necessary there is that you see the greasy ends are in the same vicinity and the watery ends are in the same vicinity, and that allows them to generate these sheets. A greasy layer and a watery layer, like a cake. A greasy cake layer and a watery cake layer, and greasy cake layer and watery cake layer. Interesting thing about this is that, if I’m light, and I’m going through this, it’s different for me if I’m going through this way than if I’m going through that way. Light is going to behave differently depending on when it is coming up through the bottom of the cake or coming in through the sides of the cake and we’re going to use that to our advantage when we look at the microscopy to see what’s going on on a tiny scale. Next. Alright, this was my place to remind myself that this was the end of the first half of my presentation. All of this has been on the molecular chemistry scale. In the afternoon, I’m going to pick up and talk about, well what happens to actual soap. We’re going to look at actual soap under the microscope to see what’s going on, and since I am told that I have until 9:30 that means that I have the luxury of answering questions for another 15 minutes if you have questions. Yes? KD - If you did correctly, there will be no lye left, and we’ll talk about the timescale, how long does it take for that reaction to happen? That’s a real question. When I started, somebody said well, how long is it before the lye is all used up? And I said, “I don’t know.” And we went away and I sicked students on the problem, and they sat with thermometers and stuff, you know, every 15 minutes for hours and hours and hours, so I have an answer to that question. But to answer your question right now, by the time you are selling your soap, the lye is all gone. There’s no lye left in there. KD – Okay, there’s two ways to label soap. And you know you’re talking to a professor when you can never get a straight answer. So there are two ways you can label your soap. You can tell your customer what went into it, or you can tell your customer what’s actually there. The easier thing for you is to tell them what went into it. And that’s the thing that you have the most control over. If you look at a soap label from Proctor & Gamble, it’s going to list sodium palmitate. It’s not going to list palm oil. Their listing the things that are in the soap rather than the things that went into making the soap. So you get a choice which way you want to label it. It’s also, if you’re just selling soap, you’re not required to list the ingredients at all. KD – You can make no claims, you can’t say this is my gentle to the skin soap. You can’t say this is my anti-aging soap. You can’t say this is good for poison ivy. All you can say is it’s soap. If you do that, you don’t have to label the ingredients. I’m going to encourage you to label it anyway. People have allergies, and they appreciate knowing what’s in their soap. Now, if you’re going to label it, you have to label it correctly. There’s a book by Marie Gale, and it’s all about labeling requirements for soaps and cosmetics. It’s a thin little book, it’s not very expensive, and anybody that’s in business ought to have that book to help them figure out the labeling part. KD – It’s, I don’t remember the name. It’s something like “Soap Labeling, Cosmetic Labeling”, but if you look up Marie Gale on the internet, on the Handcrafted Soap Maker’s Guild will have that book on their site. KD – I myself have food allergies, and it’s a life-threatening thing for me. I have to know what I’m eating. And your customers, you don’t know, they may be the same way. I would encourage you to label your ingredients one way or the other. What else? KD – Yes, so in the second half I’m going to talk about why does it gel sometimes, why does it not gel. Can I make it gel, can I prevent it from gelling? Is there any difference between whether it gelled or didn’t gel? We’ll get into all that in the afternoon. KD – Yes, so, if we just want to parse this. If I’m at a low water soap, how hot does it have to get before I get to gel phase? Gel phase is up here. If I’m at a low water environment, how hot does it have to get to gel? KD – No, this is where it starts gelling, but you aren’t going to see it. You’re not going to recognize it as gel phase until it’s all the way up here. So, a low water soap is not going to gel until well above 200⁰. Do you ever process at 200⁰? Hardly anybody ever does that. If you’re doing a low water soap, my prediction to you is, you’re never going to see gel phase. If you’re a high water soap, how hot do you have to get before it gels? Like 140⁰. Is that an area where people process? Yeah, it is. So people in the high water end will reach gel at a lower temperature. The less water you use, the higher temperature is going to be. And people are talking about hot process, I’m not necessarily talking about hot process, because even a cold process soap gets hot. So that’s why sometimes when you’re making a cold process soap, one time you saw gel and the other time you didn’t see a gel, and even more interesting, sometimes – has anybody ever seen a partial gel? Sometimes you see a partial gel. Why is that? Why did I see a partial gel? And I don’t want to steal from this afternoon, well I’ll have an answer for you. Derek, you had a comment? DH – Organic soap. How can soap be organic if it’s got lye in it? Can you call soap organic? KD – That’s a good question. That’s a legal question. I’m not a lawyer. He’s saying, “Can you label soap as organic when it has sodium hydroxide in it?” Okay, and people use the word organic in different ways. As a chemist, all I mean when I say organic, is it has carbon in it. So, benzene is organic to me. You know, benzene is associate, you know, it’s a cancer causing chemical, blah blah blah. Lots of horrible, horrible - strychnine, organic. Lots of things are organic to a chemist. But you guys use the word organic in a different way. You mean, organic means it hasn’t been made with pesticides, there’s all kinds of legal requirements for what, when you label something organic in commerce means. It’s a legitimate question, can you label any soap as organic? As a chemist, I would say, well I would say both yes and no. If I’m using my word organic, obviously it has carbon in it so we’re perfectly good. If you’re saying, oh, I understand you mean it hasn’t been made with pesticides, etc. etc. You know, sodium hydroxide is not organic in any shape. I would not label it organic myself. But now, we’re really talking about a legal requirement. Is it legally organic when it used organic, certified organic oils and sodium hydroxide? That is a term that can be defined by lawyers and legislators. And I think they’re still sort of in a quandary as to whether that’s what they want to do. Obviously, the soap makers want to distinguish a soap that was mad with certified organic oils from a soap that wasn’t, so I think eventually we’ll come down to a place where, there is a place for a certified organic soap. I think right now, legally, the most you can say is that it’s made with certified organic oils. And at least that gives your customer an idea of what they’re buying. KD – And if that’s the direction you’re going, you’ve got to jump through all kinds of hoops to make sure that you can legally use those words on your product. KD – Okay, so I’m going to answer as a chemist, and my answer is no. Because you’ve got a molecule with 3 fingers on it, the lye is going to clip each of those fingers off. Okay, but now I’m going to answer as a consumer. If I care about organic stuff, if I care about not using pesticides, if I care about all that stuff, I care whether or not you’re lying to me when you tell me what’s in your soap. And now, if you’re charging a customer who cares about an organic product, you have a responsibility to be honest with that person. KD – Chemically, I think not. But why are people interested in organic. They’re interested for two reasons, one is they think that ordinary oils would have something dangerous in them. Okay, they also think, I don’t want to promote practices that I don’t agree with. I don’t want to promote the use of pesticides. I don’t want to promote the destruction of rain forests. There are political aims that people have when they buy products. This is the beauty of the business you’re in, because Proctor & Gamble cannot market to those people. There aren’t enough of them. They couldn’t set up the smallest experimental plant to produce a soap that you can do very easily. If you have a customer that has a fetish for macadamia nuts, you can make them ten bars of soap with macadamia nut oil. Proctor & Gamble can’t compete with you. So when you’re marketing to the health food, organic, if you’re marketing to that segment; if you ask me, is the soap physically different, is there a danger element to the soap that was made with non-organic oils, my answer would be no. The amount of pesticide in it is so small and it’s a wash off product. It’s never going to bother you. If you lied to those people, and sold them soap, claiming that it was organic when it wasn’t, there is probably not a chemical test that they could even pay for that would distinguish that soap from the certified organic soap. Nevertheless, the people that politically want to promote non-use of pesticides, rain forest preservation, they deserve to have people that will sell them the kind of soap that they would like to buy. Does that answer your question? KD – It’s a regulatory mess, and these are all legal questions, not chemical questions, and it’s all a regulatory mess. KD – Is it worth it; it depends on who you are. If you’re Vermont Soap Works, that’s their whole shtick. Every product they make is certified organic, and is it worth it to them to go through the regulatory hoops and I can tell you, oh yeah, it is. They are running a great business. Is it worth it to you? If you’re making bars of soap, probably not. But if that’s the direction you want to go, you need to at least be aware of the hoops that need to be jumped through in order to, and all we’re talking about here is labeling, right? Because you can use certified organic oil and then not claim it on your label. So we’re not really talking about a difference in products, we’re just talking about a difference in labeling. KD – Not worth it for you, but it might be worth it to somebody in this room. And it might not be worth it to them today but it might be worth it to them five years from now. KD – So you think about how does pesticide get applied. It gets applied as an aqueous product. They have bins of chemicals, of nasty, horrible chemicals have been dissolved in water, they are sprayed out of airplanes or however they’re applied. Then it gets rained on. Then the crop gets harvested and it gets pressed. And what are you getting out of it, you’re getting the oil. Now, if you think about the pesticides, what were they? Were they oily or watery? They were watery. So, if you said to me, “Oh, horrible, nasty pesticide molecules are making it into the oil,” my answer to you would be “That would surprise me.” But, have I gone and taken an oil and analyzed it chemically, I haven’t done that so I can’t tell you. KD – That would also surprise me. It’s soap. By the time the lye gets finished with it, it’s three angry caterpillars floating around, and whatever else was in there, is pretty much eaten up by the time you get it to soap. KD – We always use, and I’m going to use a different term, we use deionized water. Distilled water has been heated and boiled and the steam has been collected. We have huge filters that filter out all the ions. The main thing for us is that we want to use a water that’s reproducible from one batch to the other. For the soap guild one year, I wanted to do a demonstration and I made up like 80 bottles of this demonstration stuff, and you shook it up to make suds. And I shook it up and there were no suds. And I thought, what? It’s soap and water, how in the world are there not suds in here? And I had used tap water, and our water at school is hard. It’s hard and acidic, which was exactly what I didn’t want. So we always use deionized water because we don’t want to be fooled if you made one experiment with deionized water and one with tap water, and you didn’t pay attention to that. You might get a result that you are attributing to something other than the difference in water. So we always use distilled or deionized water. If you’re doing experimental work, I would encourage you to use, whatever water you use, use the same water all the time. And the easiest way to get something that’s controlled is to use distilled water. KD – It depends on how hard your water is. If you are on well water, and it can be all over the map with well water. At my old house, we had horrible hard water, and at my new house, not so much. KD – So the thing that happens with soap is, two oxygen atoms and I’m, this is the last question, the two oxygen atoms are negative, and metal ions are positive. So what happens is calcium and Iron particularly – calcium sticks on to that, these are now neutralized, they’re not so attracted to water molecules like they used to be and so this thing falls to the bottom as you know it, as soap scum or bathtub ring. Now imagine it in your manufacturing process, you’re building the bathtub ring right into your product. Is that what you want? I don’t think it’s what you want, but depending on how hard your water is, is there half a percent bathtub ring, is there five percent bathtub ring, it’s going to depend on how hard your water is. The harder your water is, the more I would encourage you to use distilled water. And distilled water is expensive because you have to heat it. If you’re going to go to a larger scale, you might look at a water softener or a deionizer, or reverse osmosis will do the same thing. KD – If you’re going to the grocery store they’re just going to have distilled water, but if you want to buy equipment, you can buy water softener, that would be a less expensive option. Reverse osmosis would be a little more expensive, and a full-out deionizer would be the most expensive. That might be worth it to something that was producing thousands of bars a week. But might not be worth it to someone who is producing ten pounds a week. Alright, thank you for your attention.