introduction to soapmaking

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this page is not "soapmaking 101" -- it's merely a presentation of some facts about soapmaking and an overview of the various processes. i'm not offering complete and detailed instructions on all of the processes here [on this page].
the topics covered below are:
history of soapmakingmaking cold/hot process soap
soapmaking processesmaking m&p soap
a word on glycerinmaking hand milled soap
a word on curing and bar hardness

i do, however, expand on "my" approach to the various soapmaking processes on their respective pages:
i've chronicled my adventures with cold process and hand milled soap on the making "soap from scratch" page.
the "whipped soap" page details an inovative variation on the cold process that requires no cooking, no tracing, and no gelling. it produces a light fluffy bar that floats, and the process itself allows for a wider creative range.
making liquid soap requires a rather intricate form of hot process which starts out like the hot and cold processes listed below, but takes off in a completely different direction. the process is not included here but is addressed in detail on the "liquid soap" page.
the "cream soap" page(s) cover the process(es) for making this wonderful thick soap that stays soft and ranges in texture from that of a thick pourable batter a fluffy whipped cream a thick frosting ...depending on the formulation and processing method you choose.
i do go into detail, below, on the m&p process, since the soaps featured on my "designs and recipes" page use that process, and the page itself just covers the design and recipe for each soap listed. it doesn't really go into detail about the overall process.
the "transparent m&p" page covers my process for making not only a transparent soap, but a base that can be used in any m&p application.
history of soapmaking
while the origin of soap is not well documented, it appears to have been available to the early civilizations of the fertile crescent after 2000 b.c. during this epoch soap was used as a wound medication or hair dressing because the cleansing properties had not yet been discovered. even the well chronicled baths of queen cleopatra were absent of soap. essential oils were used for her bathing rituals. cleopatra used fine white sand as an abrasive agent for cleansing.
the grand baths of early ancient rome employed cosmetics, essences, and oils but no soap. later some romans understood the cleansing properties of soap, but its use was not widespread. arabs in the arabian desert and later the turks were the first societies to recognize the value of soap. when the turks invaded the byzantine empire, soap was introduced to europe. however, isolated tribes of vikings and celts discovered soap independently. the celts are even credited with introducing soap to england around 1000 a.d.
it is not until the 13th century that the history of soap making becomes more concrete. marseilles emerged as the first great center of soap making and remained an important producer through the middle ages. genoa, venice, and bari in italy came to rival it, as did castila in spain. each of these regions had a plentiful supply of olive oil and barilla (a fleshy plant whose ashes were used to make lye). this formulation became the standard through the 17th century. in the early 18th century, a number of poor olive harvests induced soap makers to investigate the use of other oils rather than olive. parallel advances in steam navigation improved the access to oils from far away ports. these changes resulted in a modification of the basic soap formulation from olive oils to a carefully selected blend of fats and oils.
though a fair amount of soap was being produced, it was most often used for laundering. it is worth mentioning that until the 18th century people did not consider cleanliness a positive virtue and bathing a social norm. in the 18th century bathing came into vogue as a medical or restorative treatment. water was considered a magical fluid which if correctly applied could be benefical for all manner of infestation. as more doctors prescribed the water cure, the idea of bathing slowly became acceptable. at the same time non medical bathing became increasing popular in europe. advances in plumbing, including running water and bathtubs which could be drained, took soap over its last hurdle for mass acceptance. soap manufacturing thrived in europe and england.
as soap was not here when they arrived, early settlers where required to make it themselves. making soap as far as the settlers were concerned was women's business. the women stored cooking grease and animal fat all year long for soapmaking day, a yearly event that preceded spring cleaning. ashes from the fireplaces were also stored to make lye. rainwater was trickled through the ashes to leach out the lye contained in the potassium salts of the burned wood. a fresh egg was used to determine whether the lye was of proper strength. if it sank slowly, all was well. if it floated, the lye was thought to be too strong, and would have to be diluted; if it dropped, the lye was too weak, and would be run through the "ash hopper" again or boiled down.
solid fats would have to be rendered, and then all fats boiled and skimmed to rid it of extraneous hair, dirt, spices, and other debris. then it would be strained through a fine cloth. the lye was then stirred into the fats. if the mixture formed a thick ingredient the project was successful. if it separated, they tried again. this process would take most of the day to complete. over 150 years passed before some enterprising persons decided to produce soap for mass distribution and consumption. these early soap entrepreneurs appeared in the mid 18th century. they made rounds of local households, purchased their stored fat, and sold the soap back to housewives. they were called tallow chandlers and soap boilers.
the soap was first peddled door to door. eventually it was distributed in general stores, where it was sold from enormous blocks. customers would indicate how much they wanted and the amount would be cut off and wrapped for carrying home. in 1806 william colgate opened up a soapmaking concern in new york called colgate & company which was to become the first great soap making concern in this country. it was not until the 1830's that the company began selling individual bars in uniform weights. in 1872 colgate introduced cashmere bouquet, a perfumed soap.
the soap market becomes competitive: at the same period that colgate & co. introduced cashmere bouquet, a perfumed soap, william procter and james gamble set up business together in cincinnati. the two sold candles and soap house to house from a wheel barrow. within a few years procter & gamble became a large manufacturer and distributed large quantities of products to major cities along the ohio river, including pittsburgh, memphis, and louisville. in 1879, procter and gamble introduced ivory soap to the marketplace. in the western united states, the b.j. johnson company was making a soap entirely of palm and olive oil. the soap was popular enough to rename their company after it - palmolive. it should be mentioned that today's palmolive soap is not the same as the original. in the midwest, a kansas based soap manufacturer known as the peet brothers merged with palmolive to become palmolive-peet. in 1928, palmolive-peet joined the colgate company to create the colgate-palmolive-peet company. (in 1953 peet was dropped from the title, leaving us with colgate-palmolive.) meanwhile, lever brothers, an english firm, sent over some of their staff to get things started in the united states. the company introduced lifeboy soap in 1895.
the establishment of these major players transformed soap into a multibillion-dollar industry. each of these companies were very competitive and determined to make their product the market leader. advertising in the form of promotions and print advertisements was the primary communication tool used to sell soap at this time. this intense competition lead to the introduction of laundry detergents in the early 1900s and aggressive radio and television advertising later.
some facts about basic soap: soap is made by mixing fat with an alkali, a process called saponification. in days of old, soap makers added the ashes of plants like the soapwort and barilla for their alkali. since the late 18th century, when someone figured out how to synthesize the active ingredient, sodium hydroxide (lye), soap makers have been combining lye with fats to make soap. most soaps are made from animal fat. soap makers have been using it since a phoenician boiled-up some goat fat with wood ashes about 2,500 years ago. why animal fat? it s cheap and makes a hard long lasting soap. however, these soaps often tend to make ones skin dry and cause irritation.
the second stage of soap manufacturing entails the addition of perfumes, dyes, superfats, chemical stabilizers, brighteners, and anti-oxidants to the soap base. these are mixed, milled on huge granite rollers to distribute the additives evenly, then compressed and extruded in a continuous shaft to be stamped and wrapped.
what distinguishes vegetable based soap: these soaps use emollients extracted from vegetables such as olive, peanut, palm, safflower, soy bean and coconut oils, instead of animal fat. combined with alkali and spring water, the fat from vegetable oils produces a soap which tends to make the skin feel soft and smooth while helping to retain natural moisture. the ingredients are then so thoroughly mixed together they appear to be homogenous. this process can take as long as 2 hours. fragrance oils and/herbs are added to provide a distinct aroma.
after mixing, the soaps are poured into a stainless steel tube where they are allowed to set for 24 to 72 hours, depending upon the herbs and oils added. after setting they are slowly pushed out of the stainless steel tube and cut. the soaps are neatly stacked to afford maximum exposure to air while they cure for 2 to 4 weeks. finally, the soaps are packaged for use.

soapmaking processes
what is cold process (cp) hot process (hp) soapmaking?
soapmaking is a craft and profession which extends back in time for thousands of years. today, most people buy their soap from commercial vendors such as proctor and gamble, ivory, etc. but handcrafted soapmaking has recently seen a resurgence both in availability and in consumer interest. as with any handcrafted item compared to a commercially produced item, hand made soaps often use more expensive and exotic raw materials and result in a soap bar which is unique and luxurious. "soap" is created when fixed oils such as palm oil and coconut oil are blended with sodium hydroxide (known more commonly as "lye"). the laws of nature demand that you cannot make soap without lye. so, cold process soapmaking involves working with oils and mixing them with lye which has been dissolved in water. as the two are stirred together, a chemical reaction begins in which all the ingredients are turned into a salt called soap. a properly made bar has no free lye in it, and is gentle and cleansing. once you get past any concerns you may have about working with lye, cold process soapmaking is a relatively easy process. with the proper tools in hand, you can produce several bars of soap in a few hours, in the comfort of your kitchen. the soap will still have to cure to finish saponification (the chemical process by which lye and fats are converted to soap). hot process soapmaking starts out the same as cold process but the soap is cooked in order to complete saponification. no curing is required with the hot process.
what is melt and pour (mp) soapmaking?
quality melt and pour is a soap based product and not a detergent. however, it may contain detergents. in general, m&p is around 50% soap and the balance is solvents. it is formulated to withstand re-melting and accept additives. it does not have to be vegetable based, although, most suppliers carry vegetable based m&p. it also does not have to contain "glycerin". the glycerin may be extracted from the soap and other solvents used to render it transparent. all melt and pour begins its life transparent. transparent and opaque m&p bases are exactly the same with titanium dioxide being added to the transparent base to whiten it and render it opaque. plain glycerin soap is not the same thing as m&p soap. many of the plain glycerin soaps on the market are formulated to not melt easily as this prolongs their length of use. this is not to say it is impossible, just remember that plain glycerin soap wasn't designed for soap casting and you will probably have difficulty with more complex designs and techniques. you can use m&p soap as soon as it is cool and firm. unlike cold process soapmaking, the saponification process has been completed at the manufactures so you don't have to allow your m&p soap time to cure before you use it.
what is handmilled soapmaking? (aka: rebatching, working with soap curls)
hand milled soapmaking is a process where you take scraps of pre-made soap or vegetable soap curls, add a liquid and cook it down to a soapbase. this method is also know as "re-batching". -- (this is not to be confused with the "milling" process by commercial soapmakers where the grated soap is mixed with the additives and is milled on huge granite rollers to distribute the additives evenly, then compressed into bars.) -- a soapmaker who has some scraps left over, rather than throw the scraps out, may choose to re-batch them into a new bar of soap. a soapmaker who wants to make a bar of truly natural soap but doesn't want to work with lye, may choose this process. while the concept is simple, re-batching soap is actually difficult enough that many soapmakers refuse to do it. the main problem is that no soap base is 100% the same from batch to batch. even if made from the same recipe, each batch will have a slightly different moisture content, will be slightly more or less alkaline, etc. so, becoming a successful re-batching soapmaker requires practice. over time, the diligent soapmaker will develop a keen eye for when to adjust temperatures and moisture content during the re-batching process. soapmakers either love this method or hate it! the good news is that a re-batch will never fail completely (unlike cold process soap). handmilled soap will always be usable soap. done well, the results are wonderfully creamy and airy. done poorly, the results are less visually satisfying, (i.e. lumpy and uneven), but always usable.
what's the difference between handcrafted and commercial soap: large, commercial soapmakers use none of the "handcrafting" processes listed below. rather, they have developed advanced means of soapmaking which result in more soap being produced faster and to their specifications. there are a couple of essential differences between handcrafted soap processes and those used by larger manufacturers.
one primary difference is the glycerin content. commercial soapmakers use a process called "salting out" to remove the glycerin from their soap stock. they do this for a couple of reasons.
first, glycerin is an expensive and useful product. commercial soapmakers can make good money by removing it from soap (which people like to pay very little for) and putting it into their lotions and creams (which people will pay more for), or by reselling it to other industries which use glycerin (candy makers, etc.).
also, commercial soapmakers have developed processes for making soap which require that the soap stock be ground up, milled, and otherwise manipulated. they need their soap base to be fairly "plastic" and to move easily through their equipment. extra glycerin makes the soap too sticky to do this.
(by the way, commercial soapmakers can skip this process entirely by starting their soapmaking process with the acid components of oils such as stearic acid and palmitic acid rather than working with the full oil. these acids do not result in excess glycerin in the soap base).
another big reason why handcrafted soaps are different than commercial soaps is that commercial soapmakers often use detergents and other additives to their bars which many people find irritating to their skin.

what is glycerin?
when asked why their soap is better than store-bought, cold process soapmakers say (among other things), "because of the natural glycerin. glycerin is a humectant, meaning it attracts moisture to your skin. glycerin is a natural by-product of the soapmaking process and while commercial manufacturers remove the glycerin for use in their more profitable lotions and creams, handcrafted soap retains glycerin in each and every bar." melt and pour soapmakers respond similarly, "commercial soaps remove the glycerin for use in more profit producing lotions and creams, my soap has extra glycerin added to it. this helps make it clear, and also makes it a lot more moisturizing."
but what is glycerin, really? glycerin is a neutral, sweet-tasting, colorless, thick liquid which freezes to a gummy paste and which has a high boiling point. glycerin can be dissolved into water or alcohol, but not oils. on the other hand, many things will dissolve into glycerin easier than they do into water or alcohol. so it is a good solvent. glycerin is also highly "hydroscopic" which means that it absorbs water from the air. for example, if you left a bottle of pure glycerin exposed to air in your kitchen, it would take moisture from the air and eventually, it would become 80% glycerin and 20% water. because of this hydroscopic quality, pure, 100% glycerin placed on the tongue may raise a blister, since it is dehydrating. diluted with water, however, it will soften your skin. (note: while people say this softening is the result of the glycerin attracting moisture to your skin, there is heated debate as to whether or not the glycerin has some other properties all its own which are helpful to the skin. summed up, the current thinking is "we know glycerin softens the skin. some people think its because it attracts moisture, but there could be other reasons.")
up until 1889, people didn't know how to recover glycerin from the soapmaking process, so commercially produced glycerin mostly came from the candlemaking industry, back when candles were made from animal fats. in 1889, a viable way to separate the glycerin out of the soap was finally implemented. the process of removing the glycerin from the soap is fairly complicated . in the most simplest terms: you make soap out of fats and/or oil and lye. the fats already contain 7% to 13% glycerin as part of their chemical makeup. when the fats and lye interact, soap is formed, and the glycerin is left out as a "byproduct". but, while it's chemically separate, it's still blended into the soap mix. while a cold process soapmaker would simply pour into the molds at this stage, a commercial soapmaker will add salt. the salt causes the soap to curdle and float to the top. after skimming off the soap, they are left with glycerin (and lots of "impurities" like partially dissolved soap, extra salt, etc.). they then separate the glycerin out by distilling it. finally, they de-colorize the glycerin by filtering it through charcoal, or by using some other bleaching method.
glycerin is also used to make clear soaps. highly glycerinated clear soaps contain about 15% to 20% pure glycerin. known as "melt and pour" soaps, these soaps are very easy to work with. they melt at about 160° fahrenheit, and solidify fairly rapidly. because of their high glycerin content, the soaps are very moisturizing to the skin. unfortunately, this high glycerin content also means that the soaps will dissolve more rapidly in water than soaps with less glycerin, and that if the bar of soap is left exposed to air, it will attract moisture and "glisten" with beads of ambient moisture.

curing and bar hardness
although some remaining saponification may take place during this period,* the main purpose of the curing is to allow the remaining water (all except approximately 16%) to evaporate. this leaves behind a hard bar which last longer ...the longer the curing time, the harder the bar. an uncured (soft) bar would simply "dissolve".
* further saponification during the curing process will cause the bar to get milder, but the amount of saponification, if any, will only be slight. most of it takes place during the first 1 to 3 days, at which point, if your soap is harsh (read lye-heavy), no amount of curing is going to turn it into a mild bar.)
with the cold process method, curing times vary from 3 to 6 weeks (depending on whose recipe you're following). with the hot process method, the soap is "cooked" during which all the saponification takes place, so when you're finished, (i.e. when the soap is unmolded), it's ready to use. however, the soap is usually allowed to sit for a couple of days to fully harden.
m&p soap: this soap needs no curing time whether in its original production or when being re-melted and reformulated. the soap is liquid at 140°f and solidifies at room temperature. you can make this bar harder by adding beeswax or stearic acid, either of which will cloud the bar's transparency.
cold process: the standard curing time for regular cp soap is four to six weeks.
a variation on this is the cold process oven process method (cpop), where the molded soap is placed in a preheated oven at 170°f to 190°f for one to two hours ...the higher temperature, the lesser time. after this time, the heat is turned off but the mold is left in the oven overnight (10 to 12 hours) and unmolded in the morning. this "cooking" speeds up and completes the saponification and cooks off [most of] the water. take the soap out of the oven, let sit a few hours and cut. when the soap is completely cool, it ready to use, however, for the soap to fully harden, it will still need to cure approximately three days to one week (two weeks for 100% olive oil soap). note that the success of this process depends on discounting the usual amount of water used in making cp soap (say, to 30%).
hot process: with this method, once the soap reaches trace, it is continually stirred while being heated ...(on the stove top, in a crockpot, in the oven, in the microwave ...there are many approaches to this process) ...until it becomes thick and gloppy. this cooking completes the saponification and cooks off [almost] all the water. when the is soap cool, it's ready for use. however, the soap is still somewhat soft, and a little curing is still needed (say, 3 to 7 days) to fully harden the bar. the above-mentioned cold process oven process is actually a form of hot processing called in the mold hot process (itmhp).
rebatching: the cooking during this process removes a lot of the water and the usual curing time for rebatched soap is 2 to 3 weeks. however, the determining factor is the moisture content. was the soap fresh or had it already been cured? did you have to add any liquid to the process? note that the more liquid you add, the easier it is to handle the soap, but this results in a lot of shrinkage and warping while drying, resulting in an unattractive bar.
the above "shorter" curing times refer to minimum curing times. obviously, a longer curing time would result in an even harder bar. in the end, there is no way to "test" when curing is complete. so much depends on your particular environment and production method. experience will dictate when a bar has cured enough.

instructions for making cold processed (cp) and hot process (hp) soap
the following instructions are just to give an overview of the cold process. Before attempting to make cold (or hot) process soap, you will need exact instructions with a recipe giving exact measurements.
in addition to the information contained in my "soap from scratch" page, i would suggest [for anyone seriously considering a venture into the world of cold process soapmaking] a visit to "kathy miller's soap pages". here you'll find a ton of detailed information as well as some interesting recipes. this is but one of many, many internet sites with soapmaking information, but this is a good start.)
measure each of your ingredients carefully according to whatever recipe you are following. always use an accurate scale to measure your lye, oils, and additives. water is typically measured by volume (which means using a measuring cup instead of a scale), but recipes can vary on that point so check your recipe before starting.
measure your lye very carefully. then, carefully pour your lye into your water (or other liquid). never, ever pour the liquid into the lye! this can cause an explosive "volcano" of extremely caustic liquid that can burn or blind you. please, please, be ultra careful with sodium hydroxide and potassium hydroxide! wear latex gloves, protective eye goggles, and an apron whenever you handle caustic materials.
combine your oils in a pot over the stove and heat them until they're the desired temperature. generally, soapmaking recipes call for a temperature between 100° and 140° fahrenheit. higher temperatures can seize, lower temperatures take longer to trace.
get ready to mix your soap! gather all your tools and materials and have them handy.
if you choose, decant your oils from your melting pot into a stainless steel or glass mixing bowl.
once you have reached your desired temperatures, slowly pour the lye-water into the oils. your mixture will turn cloudy as you combine the oils and lye. eventually it'll turn into a milky, pudding color. when it is a pudding texture, and your spoon leaves "trails" when you stir (imagine making instant pudding; when the pudding is "set" your spoon leaves trails through the pudding), you have reached trace. -- ("trace" is when the mixture is very thick, about the consistency of a milkshake or honey. when a little is dribbled from the stirring spoon onto the surface, you'll be able to clearly see a trace on the surface ...try writing your initials.) -- it will only take 15 to 30 minutes to trace, however three hours isn't uncommon, so be sure to do this when you have lots of time. sometimes, you can use a stick blender to help speed things along.
once you are at a light trace, add your superfatting oils (if you choose to keep them separate until trace), fragrance or essential oils, and any herbs or other additives. mix everything together until it's well combined and homogenous.
once you've completed mixing your additives, immediately pour your soap into your mold or molds. cover the mold with plastic and wrap with blankets. leave undisturbed for 24 hours. after 24 hours, remove from mold and slice into bars. set bars in a dry place to age for two to three weeks before using. (note: the soap will be safe to use after 3 weeks, but it will still be somewhat soft and won't last very long in the bath/shower.)`

a variation on the cold process soapmaking theme is the hot process. the two methods start out the same, but with the hot process method, you cook the soap while you stir. constant exposure to heat makes the oils and lye interact more quickly and more thoroughly than in the cold process method. with the hot process, saponification takes place during the "making" and no long curing times are required. the advantage of the cold process is that you have greater control over the soap and the additives. like cold process, hot process soaps can also be made at home, however there are few books currently available on the topic. there is, however, an abundance of information on the internet from various sources.

instructions for making melt and pour (mp) soap
melt the soap:
the best and recommended way is to melt the base is in a double boiler with the cover on. your goal is not to have the soap pan directly over the heating element. this will cause your soap to get too hot. you will want to keep the double boiler covered to prevent a thick layer of soap from drying on the top of the melted soap and to prevent moisture loss.
a second method is to use a microwave. a microwave can be used safely with some soap bases. use a medium setting and short times. each soap base is formulated differently so check with your manufacturer. melt the soap base slowly and avoid boiling.
the soap melts at about 140 degrees. you can use a thermometer, but this is not really necessary. the key is to not let your base boil or get too hot. there are three reasons for this. firstly, you will evaporate too much water from the base and it will become brittle and prone to cracking. secondly, you may caramelize the sugars in the base and it will change color and loose transparency. lastly, it just smells bad.
a good method for keeping the soap at its lowest temperature -- there are some techniques that require working with a cooler soap base -- is to melt the soap about half way in the double boiler, then cover it with a lid and turn the heat off. the hot water and time will melt it the rest of the way.
you don't need to add any water to your soap base, however, if you're re-melting base that has been melted down multiple times, add a bit of water to compensate for the previous evaporation.
you can give the soap pieces a gentle nudge to encourage melting, but do not stir vigorously, as this will incorporate air bubbles into the base. this is also the case when incorporating colors, scents and other additives; all you need is gently stirring.
add fragrance:
once the soap base has turned to liquid, remove it from the heat. add your essential oil or cosmetic grade fragrance oils. please do not use candle or potpourri scent oils. they were not created to be applied to your skin and can cause severe reactions.
it is recommended to add about 1/4 tsp. (25 drops) to a maximum of 1 tbs. (300 drops, 1/4 oz.) per pound of base. but oils differ in strength and noses in sensitivity. it's best to start with a smaller amount and add more as your personal preference dictates.
one key thing to remember is that each scent has a "flashpoint", this is the temperature at which the scent "whooshes" into the air and burns off. some fragrance flashpoints are quite high while others can be as low as, say 120 degrees. since our soap base melts at about 140 degrees, this means it must be as cool as possible to retain fragrances. it's best to get into the habit of adding your scent when your soap is its coolest, just before pouring into the molds ...or alternatively, add the fragrance when the base is about 3/4 melted (off heat and covered). this allows it to be distributed throughout the base without being subjected to excess heat.
add colorant:
for your protection, it is recommended you use cosmetic grade colorants. just because a company says a color is safe for soap, it doesn't mean that the color is cosmetic grade. the fda has very loose guidelines for soap colors. cosmetic grade colors meet very strict guidelines and give you the most protection.
you will want to add a cosmetic grade colorant. add the color very slowly because it is easier to make it darker and impossible to remove color. if you are using color creams you'll want to microwave the cream for 20 seconds and mix with a small amount of melted soap. once mixed, you can then add the small mixture to the larger batch of soap. if you are planning to reproduce your soap, you may want to use specific measurements so you'll know exactly what to add to produce the same results. there are different color additives available from different suppliers. the best direction is to follow the directions from your supplier.
cosmetic quality mica is a transparent mineral [mined from the earth] that adds a pearlescence to your soap. best used in clear m&p soap, (because the mica needs light to shine and shimmer), mica adds dimension as well as color and greatly broadens the scope of creative possibilities.
food colors work and are safe. however, they are not designed to be used in soap and the colors will fade and/or mutate. you may also use herbs, spices and juices to color your soap. you may add them directly to your soap but remember that whatever you add will come in contact with your skin, so you don't want to add anything to scratchy. you can also make a tea or infuse oil with herbs and/or spices and strain this before you incorporate it into the base.
you should note that some fragrances may naturally color your base. for example, vanilla may change the color of a white soap base to a lovely caramel. many florals will turn it slightly yellow, lemongrass will turn it more yellow, and spices will turn it slightly brown. the color change may not be immediate. you may find that it is weeks later that your soap has changed color due to the fragrance. some fragrance oils (if they contain certain levels of alcohol) can actually make your [transparent] soap more clear.
other additives:
you can add lots of things to your soap base, dried herbs, ground spices, luxury butters such as shea or cocoa, cosmetic clays, and of course dried flowers. a word of caution: many herbs and flowers turn brown in soap ...chamomile and calendula are two flowers that retain their color, lavender and rose petals do not.
using additives, you can customize your soap to meet your particular needs. you should be aware that each additive has its own characteristics and affects the final product and its performance in a specific manner. if you add oils [or butters], you may also want to add a preservative, (i.e. vitamin e), because the oil will mold over time. honey, [goat's] milk, ground oatmeal, and cosmetic clays are just some of the other additives that you can incorporate into your soap. see "additives" for an list of the additives used in the m&p soap recipes featured on this site. this is but a sampling of the myriad possibilities.
changing the nature of the soap base -- a soap base will accept up to 1 cup of extra liquids per pound of soap. these extra liquids include scents and oils:
to make it harder: add 1/4 ounce beeswax per pound of soap. this will make a transparent base less clear.
to make a transparent base clearer:
add 1/4 cup of high-grade alcohol per pound of soap. alcohol can make the soap more drying and impart an odor, or
add 1/4 cup water. this will also make the soap softer, or
add 1/4 cup glycerin. this will make the bar softer, clearer, more gentle to the skin but more prone to "sweating", or
add 1/4 cup sugar water in a 50/50 solution. this will make the soap clearer and softer but can make it more sticky.
emollient additives:
you can add all sorts of things: olive oil, jojoba oil, shea butter, cocoa butter, vitamin e, etc. how much depends on what you are adding. generally, it's recommend you experiment with about 1 tsp. to 1 tbs. per pound of soap. too much can result in soap that's soft and causes lots of oily residue in the tub.
herbal additives:
there are a few points to consider when adding herbs. you don't want to add anything that'll make the soap "scratchy". there's a technique to adding herbs (and other stuff) so that they stay evenly suspended and don't all sink to the bottom of the mold. some herbs don't do well in the soap. frankly, they rot and turn brown, like rose petals, even well dried ones. if unsure, make a trial batch. if the additive is going to turn brown in the soap, it'll do so within a few days.
when do i incorporate the additive(s)? if it needs to melt, add it when you're melting the base. if it needs to melt at a higher temperature, melt it separately and incorporate it into the melted base. powders can clump. the best way around this is to scoop out a bit of melted base and make a paste with the powder. incorporate this paste into the melted base. liquids may be added to the pot when you're melting your base.
pour into molds:
look for professional soap molds. you will find they last longer and are well worth the investment. pour your soap slowly into the mold. if any air bubbles rise to the top, lightly spray with alcohol and the bubbles will disappear. the easiest way to get the soap to release from the mold is to place it in the freezer for 20 minutes. then, let it sit for several minutes at room temperature. as the mold warms up it will expand and the soap will pop out.
what else can i use as a mold?
you can use anything for a mold which has some flexibility. for example, a thin aluminum container might be fine, while a glass container would be more problematic. you need something that the soap can "pop" out of. most commercial molds are designed for individual bars, but say, if you wanted to cast a "loaf" of soap to be sliced into bars, you could use pvc or abs pipe or downspout from you local hardware store, plastic food storage, organizing containers ...pretty much anything that's flexible and will give you the shape you want. the only consideration is that the mold be something the cooled soap can "pop" out of
additional notes, tips, and techniques:
most problems are the result of pouring the soap when it is too hot or attempting to unmold it when it is not fully cooled. also, when employing a technique which requires working with soap at its coolest, it's best to work on a bar by bar basis. if you're trying to do six bars at once, your soap has to be hot (read liquid) enough to complete the pour which may mean it's not cool enough for the success of the technique you're using (see "suspending herbs" below). in this instance, one method is to melt and color the total amount of soap and keep it just warm enough to stay liquid. then, remove enough soap for one bar, incorporate the fragrance and additives, and mold using whatever technique. then, move on to the next bar, repeating until all the bars are molded.
creating layered soaps
if, as an example, you want to do a "rainbow" soap, you should pour the first color into the mold and allow it to harden just enough to support the weight of the second layer. add the second layer of soap at a temperature that is cool enough so it won't melt into the first, and so forth. to encourage adhesion between layers, spritz each layer with some alcohol before pouring the next. you can repeat this as many times as you would like. don't let a layer harden completely before adding the next. don't put a layer in the freezer before adding the next. large differences in temperature between layers will result in the two layers not "sticking together" and they will pop apart when you remove the soap from the mold.
to create a surface relief (filling in the raised portions of the mold with a contrasting-colored soap), the principles are pretty much the same as with "creating layered soaps" above. however, it takes time to fill soap into the intricated designs of the mold [with a pipette], and the amount of soap is so little, it cools and hardens quickly. for this reason, the temperature of the remaining soap needs to be not so hot that it obliterates the relief, but warm enough to "slightly" re-melt it so that it adheres. otherwise, the relief details may seem to stick, but when you use the soap, they will just come off. this is a technique which requires some skill (read practice) to master.
suspending herbs
you may want to intersperse herbs or other additives throughout the soap. you should let the soap cool in the soap pot for a long while. let it form a skin on the top. when you pierce the skin, you will see that the soap underneath is thick as pudding. pour the pudding-thick soap into a separate bowl, (or you can blend right in the pot once the pan is cool to touch). blend in the herbs/additives, and stir consistently but slowly (don't create bubbles) and then pour into your molds. timing this just right ...when the soap is pourable but thick enough so your additives remains evenly dispersed another technique requiring some skill, which will improve with experience.
embedding objects
you can put toys and other items in soap, but they tend to not stay in the middle, rather they will float to the top of the mold. there a few ways you can resolve this problem.
pour a bit of soap into the mold and let it harden enough so that you can stick the toy onto it before filling the mold the rest of the way. you will, however, end up with a visual "line" where the two separate pours meet.
pour the liquid base into a mold and then cover the molds until the outside is just warm to touch. while you are waiting, spray the object with alcohol. this will encourage adhesion and dissolve bubbles that may form. once the soap is cooled, remove the lid and gently push the object into the soap.
pierce the bottom of the mold with a strong dressmaker's pin and then pierce the toy onto that pin. then pour soap around it all at once. when the soap is hard, simply remove the pin and rub out the hole with your finger.
embeding soap into soap
start with smaller decorative soaps or cut the desired shape(s) out of a thin layer of soap using a cookie cutter. then put the soaps into the freezer for a good long time. when they are cold, melt down some clear soap. let this clear soap become as cool as possible. then pour the clear soap into the molds and quickly push the frozen images into the middle. the difference in temperature between the two soaps will make them not melt together.
wrapping and packaging
m&p soap is high in glycerin content. as such, it should be wrapped in plastic wrap. the plastic wrap protects it from the ambient moisture in the air. if left out, especially in humid climates, the soap would form beads of moisture on it which are unattractive and messy.

instructions for making hand milled soap (rebatching)
(despite the apparent simplicity of the the two methods below, rebatching seems to be a tricky process. there are those who love it and those who hate. see "kathy miller's rebatching page" to get an idea of some the the intricacies of this process via the successes and failures of those who've actually been there.)
i've developed a process which is an amalgam of the two examples below. see "my rebatch" for a description of the method i've been successful with and some examples of those successes.

using this method to hand mill soap, you start by grating soap you've previously made (either specifically for this purpose or the recycling of soap from other projects), or by purchasing from a supplier soap (in the form of "curls") that's been manufactured just for this process.
you have several options for melting the soap -- do not melt your soap curls on the stove or over direct heat. if your soap turns orange, this indicates that it has cooked too long or the temperature has gotten too high. the soap, however, is still safe to use and the color may fade with the curing process.
crockpot method: place one pound of soap curls and 1/2 cup of liquid (milk, water, herbal tea, etc.), in a crock pot at about 250 degrees f or on low, cover and allow to "stew" for 1 to 3 hours depending on how many pounds you are working with. if the curls do not fill your crock pot at least half way, the oven, double boiler or microwave method may work better for you. stir gently and thoroughly every hour making sure your don't create air bubbles. after 2 hours, stir every 1/2 hour until the curls are melted and you have a mixture resembling marshmallow cream. finish -- (refer to "finishing" below).
oven method: place the soap curls and liquid a stainless steel, enamel or glass pot, cover and place in a 200 degrees f oven. stir gently and thoroughly every hour making sure your don't create air bubbles. after 2 hours, stir every 1/2 hour until the curls are melted and you have a mixture resembling marshmallow cream. finish -- (refer to "finishing" below).
double boiler method: follow the crock pot method using a double boiler instead. check water level periodically. this method may take longer. stir gently and thoroughly every hour making sure your don't create air bubbles. after 2 hours, stir every 1/2 hour until the curls are melted and you have a mixture resembling marshmallow cream. finish -- (refer to "finishing" below).
microwave method: place soap curls in a microwave safe container adding only 1/8 to 1/4 cup liquid per pound of soap curls. cover lightly with lid or paper towel. microwave on high 1 to 2 minutes, depending on your microwave. watch this mixture closely as it will expand and rise out of your container. use caution when handling container as it will get very hot. stir thoroughly and microwave at 1/2 to 1 minute intervals until you have a mixture that resembles marshmallow cream. with the microwave method, you need very little liquid ...if any at all. the absence of liquid will speed up the curing time. finish -- (refer to "finishing" below).
once you have a mixture that resembles marshmallow cream, you may add fragrance (up to 3 tsp. per pound), colorants and herbs. at this point stir. you must be quick as the mixture tends to set up fast. spoon mixture into pre-greased molds (vegetable sprays such as pam work fine). put a layer of plastic wrap over the top and press the soap into the molds completely to avoid any air pockets. allow the soaps to cool in the molds and then remove. if you have problems releasing your soaps, you may put the mold in the freezer for 15 minutes and try again. be careful as excessive force will break your molds, especially when they are cold. depending upon how much liquid you've used, you will want to age your soaps for 2 to 4 weeks so that the bars will harden (otherwise it dissolves too quickly in water).

this alternate method is designed to work with special, all natural, cold process soap base which has been formulated to require little fluid during the hand milling process thus eliminating weeks from the cure time. the soap may be ready to use in as little as 24 hours. another advantage to this new technique is that the soap is less likely to burn and turn brown.
place a 3-quart pot of water on the stovetop and bring to a boil.
grate your soap base with a cheese grater. if you do not have access to a cheese grater you can cut the soap into very small cubes.
place the grated soap into an oven bag ...the kind found at your local grocery store.
close the open end of the bag with a rubber band.
fold over the top of the bag and tie again with a rubber band.
place the bag into a boiling pot of water.
boil for 1 hour untouched.
carefully remove the bag from the water. using warming mitts, to protect your hands, place the bag of soap on a counter and knead the soap.
the soap will turn to a mushy smooth consistency. if at this point you have not reached this consistency, return to the bag of soap to the boiling water for 30 minutes. repeat as needed.
remove from the boiling water and cut the rubber band off. the soap should have a smooth and marshmallow cream consistency. if you have difficulty reaching the marshmallow cream consistency you can add 1/4 cup of water to the soap. this, however, is a last resort since it will prolong the cure time.
add your fragrance, color, and other additives to the soap base.
twist the bag and close with another rubber band.
knead the bag to completely mix the additives.
spray your soap mold with a light coating of pam or other oil of choice.
snip the corner of the bag. squeeze the soap out of the bag into the molds using the technique that pastry cooks use to decorate cakes.
smooth the top of the soap as needed.
let the soap sit until firm. unmold soap. often the bottom of the bar of soap is irregular. you can use a knife to shave the irregularities.
let the soap cure until fully hard. this will take anywhere from hours to weeks. the length of time depends on the room temperature, humidity and the amount of fluid you added, if any.