inch off of each bar to remove this substance.Adulterate — To make impure by the addition of an inferior substance.
Alkali — A substance with a pH greater than 7. Sodium hydroxide is an example of an alkali (or a base) used to neutralize an acid to make soap.
Allergen — A substance which provokes an allergic reaction in the susceptible person, but can have no negative effect on another person.
Antibacterial — If a substance is antibacterial, it fights bacteria effectively.
Antioxidant — Oxidation occurs within fats and oils, as unattached oxygen molecules wander around and latch onto other molecules, forming unstable compounds. An antioxidant is a substance that inhibits oxygen from reacting with other molecules to form unstable compounds. Within soap-making, antioxidants inhibit rancidity and spoilage of the fats and oils.
Antiseptic — A substance which slows the growth of microorganisms on living tissue. The following pure essential oils offer some antiseptic properties: cassia, clove, rosemary, thyme, sandal-wood, and peppermint.
Aromatherapy — The art of using pure essential oils from plants for their physical and emotional therapeutic effects.
Astringent — A substance made mostly with witch hazel (natural) or isopropyl alcohol (synthetic) to remove soap film and dead skin. Thought to contract tissues and close pores. Stick with the witch hazel solutions and use sparingly to avoid a drying effect.
Bacteriostatic — A substance which inhibits the growth of bacteria, but does not destroy bacteria.
Base — The alkali used within soap-making which reacts with the fats or oils to form soap. Sodium hydroxide is the base used most often by the cold-process soapmaker.
Carcinogenic — A substance that causes some form of cancer.
Castile soap — A soap named for the region in Spain where it was first made. Once a pure olive oil soap, castile soap is now generally regarded as an olive/tallow combination.
Chlorophyll — The green matter found in the chloroplasts of plants, chlorophyll contributes antiseptic and antifungal properties to soap. It is also used as a natural colorant (pale green).
Clay — Mixture of natural minerals used in face masks to draw out impurities and excess sebum.
Coal tar — A tar obtained through the distillation of bituminous coal, used to make dyes and drugs. Many soapmakers use these synthetic dyes to color soap, though studies link coal tar dyes to cancer in animals and allergic reactions in humans; try to avoid them.
Cold-Process — The most simple soapmaking method; fats and oils react with lye to make soap and release glycerin, using no external heat once the ingredients have been blended.
Colorant — Perhaps not a generally accepted word, but adopted through use to mean a substance used to dye soaps naturally or synthetically. Non-synthetic examples include chlorophyll, cinnamon, turmeric, wheat germ oil, and herbal decoctions.
Cure — The process that soap bars experience over four to eight weeks as the soapmaking reaction continues within the final bars, leaving the soaps progressively less alkaline and more mild. Saponification, the soapmaking reaction, does not end once the liquid soap is poured into frames. As soaps cure, they are incorporating any remaining sodium hydroxide — changing from harsh to mild soaps.
Decoction — An extract obtained by covering roots and bark (tough-skinned botanicals) with water, and boiling down the liquid to a potent concentration. This is often used medicinally. Soapmakers use decoctions to color their soaps safely. Expect quiet, pale earth tones instead of bright synthetic colors.
Emollient — A substance spread onto the skin to hold in moisture and keep water loss to a minimum. Vegetable glycerin and vegetable oils are natural emollients; mineral oil has always been praised an an inexpensive natural emollient, but there is concern with respect to its petroleum base, which is thought to actually dry the skin over time.
Emulsion — The mixture of two incompatible substances by a third component (the emulsifier) which helps hold all three together in a unit. Soap is an emulsifier, as it holds the dirt and oil in suspension in water. Oil and water are incompatible and soap holds them together; soap pulls the dirt and oils away from the skin and holds it to the water until a rinse washes the whole unit away.
Essential fatty acid — The few fatty acids which stand out above the others as especially effective are called essential fatty acids. Linoleic, linolenic, and arachidonic acids (known also as vitamin F) are essential fatty acids, those unsaturated fatty acids which are not manufactured by the body and are provided through diet and skin-care products, inhibiting the growth of some bacteria and protecting the skin against infection. They also have moisturizing properties. Essential fatty acids affect blood clotting, the transport of oxygen by the bloodstream to cells, tissues, and organs, lubrication and binding together of cells, and the availability of certain vitamins and minerals to the body. Oils which are especially good providers of essential fatty acids include: sunflower, safflower, evening primrose, borage, Rosa Mosqueta rosehip seed, kukui nut, and wheatgerm oils.
Essential Oil — see “Pure Essential Oil”
Extract — Often a concentrated form of plant material. Some plant material is not released completely by just a cold-pressing of the material; these plant materials are better extracted when passed through a solvent (can be organic or synthetic). Depending upon the desired state of the final product (powder, water-soluble liquid, or oil-soluble liquid), some solvents are removed after expression, and some are left as a part of the plant extract. Always ask for oil-soluble extracts, extracted without synthetic intrusion.
Fat — Primarily saturated (though not always) compounds of carbon, hydrogen, and oxygen that are attached to glycerol in the form of glycerides, obtained from animals and plants. They are normally, though not always, solid at room temperature, and they offer emollient properties.
Fatty acid — Saturated and unsaturated organic compounds of carbon, oxygen and hydrogen found in animal and vegetable fats and oils that occur naturally in the form of glycerides, a compound of glycerol and fatty acids, or what are called neutral oils. Fatty acids can be isolated from the glyceride through a process called hydrolysis. They must not be thought of as a burning acid, but rather as mild, emollient acids. Fatty acids are wonderful emollients.
Fragrance oil — A synthetic imitation of a pure essential oil. Fragrance oils do not offer the botanical properties found within pure essential oils and they often interfere with the saponification process.
Free-fatty acid — Those fatty acids which are not bonded to glycerol in the form of a triglyceride, but instead exist indepently in a “free” state. They are less stable than the complete triglyceride, and they contribute to rancidity.
Glyceride — A compound of alcohol plus an acid. Neutral oils contain glycerides of glycerol (the alcohol) plus a variety of fatty acids (the acid). When three molecules of fatty acid are attached to one molecule of glycerol, the combination is known as a triglyceride.
Glycerin — A syrupy alcohol derived from vegetable oils and released from the glycerides during soapmaking. Although often removed as a by-product of the soap industry, cold-process soaps retain this natural glycerin and benefit from its emollient and humectant qualities. Glycerin is also known as glycerol and by the trade name, glycerine.
Grapefruit seed extract — This material extracted from grapefruit seeds is used as a natural preservative within soap. It should be added to the oil phase of the soapmaking process, as it will precipitate out of the lye solution.
Humectant — A substance which attracts and holds moisture to the skin; for example, a thin layer of either glycerin or aloe vera draws moisture from the air to soften the skin.
Hydrocarbon — Chemical compounds which contain only carbon and hydrogen atoms. Petroleum products are hydrocarbons. Much controversy surrounds this group of materials: some chemists consider petroleum products as natural, since they come from the earth and were once vegetation; opponents point to their altered state once synthetics are introduced in order to refine them for personal use. These products can be allergenic and phototoxic.
Hydrogenation — The process of adding hydrogen to the double bonds of unsaturated oils to solidify them and to make them more stable against oxidation and rancidity. Warning: any benefits must be weighed against the loss of essential fatty acids which are destroyed during the hydrogenation process.
Lye — Lye can be defined as either the solid caustic (such as sodium hydroxide) or as the liquid solution made by dissolving NaOH (in this case) beads or flakes into water.
Natural — A material which does not contain synthetic chemicals. Watch for products labeled “natural” which contain some organic substances, but also contain synthetic additives or preservatives.
Nutrient — An ingredient chosen for its beneficial properties. Within soap-making, a nutrient is a material added to the formula for its ability to act upon the skin in a desired way.
Oil — Primarily unsaturated (though not always) compounds of carbon, hydrogen, and oxygen that are attached to glycerol in the form of glycerides, obtained from plants and animals. Oils are most often liquid at room temperature.
Organic — If a substance is organic, it is, or was at some point, alive and has not been altered with synthetic materials.
pH — When one hydrogen atom exists on its own, it is a positively charged hydrogen ion. The hydroxyl ion (OH — one oxygen atom and one hydrogen atom bonded together) is negatively charged and the balance of these hydrogen and hydroxyl ions within a solution dramatically affects the solution’s makeup. An imbalance leaves the solution either acidic (more hydrogen ions) or alkaline (more hydroxyl ions). pH is a scale used to measure the hydrogen ion concentration of a substance.
At pH 7, the balance is just right. When there are more positive hydrogen ions, a material is acidic, somewhere between 1 and 7 on the pH scale. When there are more hydroxyl ions, the substance is alkaline or basic, somewhere between 7 and 14 on the pH scale.
Photosensitizers — Substances which make the skin sensitive and reactive to the sun’s energy, especially light.
Potassium hydroxide — A strong, caustic base, also known as lye. Potassium hydroxide, or caustic potash, was the alkali used most throughout history to produce soap. Water steeped through wood ashes yields this caustic chemical which reacts with fats or oils to form liquid soaps and soft soaps.
Preservative — A substance used to slow down bacterial growth and decomposition. Look to natural preservatives for a one year shelf life; however, avoid synthetic preservatives which can offer years of shelf life, but adulterate a pure product.
Pure essential oil — The highly concentrated volatile oil obtained from plants which carry the scent and the beneficial properties of the particular plants. They are volatile because they evaporate quickly at room temperature when exposed to air. Watch for synthetic imitations which do not offer the botanical properties and which are less stable throughout the soapmaking process.
Rancidity — The decomposition of a substance which leads to a spoiled quality and odor.
Refinement — A process used to remove the impurities within a fat or an oil. Cold-pressed oils, those oils released without applying heat, contain the least amount of impurities and do not require refining — any impurities found within a cold-pressed oil can be filtered out. Pressing coarse meal further, while heating it, releases more oil, but this oil usually contains a higher percentage of non-glyceride impurities, like free fatty acids. Don’t think of impurities so much as unclean, inferior materials, but rather as out of solution wanderers which are less stable and more likely to react because they are separate from the neutral oil. These are the culprits which can start reacting with the wrong mates, causing rancidity of the oil, and eventually our soaps. When an oil is refined, it is combined with an alkali solution, encouraging the non-glyceride portion to react with the alkali to form soap. The soap is drawn off, leaving the oil behind to be washed of any excess alkali or soap.
Rendering — The process of heating beef fat with water and salt, eventually leaving a clean, pure tallow which can be strained, cooled, and finally sliced away from the impurities.
Salt — Compounds that result from the replacement of part or all of the hydrogen of an acid by a metal. In soapmaking, sodium hydroxide replaces the hydrogen in the fatty acids (the fats or oils) to make a salt (or soap) of those fatty acids.
Saponification — The conversion of a fat or oil and an alkali into soap and glycerin.
Saponification value — This measures the amount of potassium hydroxide (in milligrams) required to saponify one gram of that particular fat or oil. Also known as SAP value.
Setting up — (See page {00}.) As the soap mixture converts from a liquid to a solid state, the soap is “setting up.” This process should take place in the frames, and not in the soap pan. Occasionally, a synthetic fragrance oil, or certain pure essential oils will cause the soap to begin setting up right in the soap pan, making it very difficult to pour the soap into the frames.
Sebum — A fatty substance secreted by the skin’s sebaceous glands. Sebum lubricates the skin; however, without proper hygiene, the oil can build up and plug the pores, creating a breeding ground for bacterial growth, inflammation, and infection.
Soap — A mixture of salts of various fatty acids made by an alkali acting on the fatty acids. Fats or oils mixed with an alkali form soap and free glycerin; the resulting soap is a cleansing product.
Soda ash — Sodium carbonate, a grayish-white, powdery residue which forms on the surface of the soaps once they are exposed to air. Sodium hydroxide reacts with water or air to form this compound, which is not as harsh as sodium hydroxide, but is still drying to the skin. Slice inch off of each bar to remove this substance.
Sodium hydroxide — A strong caustic base, also known as lye or caustic soda. This highly alkaline chemical can combine with fats or oils to form hard soaps.
Superfatting — To superfat a soap is to leave unsaponified oils in the final bars for a less harsh and more emollient soap. These unsaponified oils do not form compounds with the other soapmaking components, but instead remain in their original form within the bars. Superfatted soaps are more prone to rancidity, but worth the reduced shelf life.
Surfactant — A substance which reduces surface tension (the tight molecular bonds). For example, water molecules are tightly bonded, so water beads up on fabric, rather than soaking in to wet it. A surfactant, like soap, breaks down the bonds and enables it to spread and evenly wet the fabric.
Synergism — When two or more substances work together to create a benefit greater than the sum of each individual benefit.
Synthetic — A substance which is produced or altered artificially.
Tallow — The fat from the fatty tissue of cattle, sheep, and horses used for thousands of years to make soap. It may, however, cause eczema and blackheads.
Tocopherols — A classification in the vitamin E group. Fat-soluble, antioxidant compounds of vitamin E that are used to preserve soap. Look for the natural tocopherol made from vegetable sources and avoid the synthetic imitations. Note that tocopherols protect tallow and lard soaps better than they protect vegetable soaps.
Triglyceride — Fats and oils found in nature are almost always found in the form of triglycerides. These are different arrangements of fatty acids and glycerol (a form of glycerin): three (tri) fatty acids link to one molecule of glycerol to form a triglyceride, which will usually contain two or three different fatty acids, rather than just one kind of fatty acid.
Unsaponifiables — The portion of a neutral oil (including squalene, sterols, and fatty alcohols) which do not participate in the soapmaking reaction, but rather retain their original makeup in the final bars of soap.
Veganism — A philosophy based upon the belief that animals should not be killed or treated with cruelty, even for the benefit of mankind. In practice, this means eating no meat, fish, honey and dairy products, including butter, eggs and milk. Vegans (those who practice veganism) choose not to wear wool, leather, or fur, and they do not use any products which have been tested for safety on animals.