Editing Soap (section)

==Soapmaking==
{{Main article|Soaper}}

The production of toilet soaps usually entails [[saponification]] of [[triglyceride]]s, which are vegetable or animal oils and fats. An alkaline solution (often [[lye]]) induces saponification whereby the triglyceride fats first [[Hydrolysis|hydrolyze]] into salts of fatty acids. [[Glycerol]] (glycerin) is liberated. The glycerin is sometimes left in the soap product as a softening agent, although it is sometimes separated.<ref name="Cavitch, Susan Miller 1994">Cavitch, Susan Miller. ''The Natural Soap Book''. Storey Publishing, 1994 {{ISBN|0-88266-888-9}}.</ref><ref>Garzena, Patrizia, and Tadiello, Marina (2013). ''The Natural Soapmaking Handbook''. [http://www.demetra.com.au/ Online information and Table of Contents] {{webarchive|url=https://web.archive.org/web/20150730033519/http://www.demetra.com.au/ |date=2015-07-30 }}. {{ISBN|978-0-9874995-0-9}}/</ref> Handmade soap can differ from industrially made soap in that an excess of fat or coconut oil beyond that needed to consume the [[alkali]] is used (in a cold-pour process, this excess fat is called "superfatting"), and the glycerol left in acts as a moisturizing agent. However, the glycerine also makes the soap softer. The addition of glycerol and processing of this soap produces [[glycerin soap]]. Superfatted soap is more skin-friendly than one without extra fat, although it can leave a "greasy" feel. Sometimes, an [[Moisturizer|emollient]] is added, such as [[jojoba]] oil or [[shea butter]].<ref>{{cite web |title=The Process of Making Soap |url=http://edtech.mcc.edu/~abaker/comw100/finalproject/process.html |website=edtech.mcc.edu |access-date=8 March 2020 |archive-date=15 July 2019 |archive-url=https://web.archive.org/web/20190715192100/http://edtech.mcc.edu/~abaker/comw100/finalproject/process.html |url-status=dead }}</ref> [[Sand]] or [[pumice]] may be added to produce a [[wikt:scouring|scouring]] soap. The scouring agents serve to remove dead cells from the skin surface being cleaned. This process is called [[exfoliation (cosmetology)|exfoliation]].

To make [[antibacterial]] soap, compounds such as [[triclosan]] or [[triclocarban]] can be added. There is some concern that use of antibacterial soaps and other products might encourage [[antimicrobial resistance]] in microorganisms.<ref name="AntibacterialABC">{{cite web |url=https://abcnews.go.com/Health/story?id=117985 |title=Antibacterial Soaps Concern Experts |publisher=ABC News |access-date=12 November 2014 |url-status=live |archive-url=https://web.archive.org/web/20141112070010/https://abcnews.go.com/Health/story?id=117985 |archive-date=12 November 2014 |date=2006-01-06}}</ref>

The type of alkali metal used determines the kind of soap product. [[Sodium]] soaps, prepared from [[sodium hydroxide]] (soda lye), are firm, whereas [[potassium]] soaps, derived from [[potassium hydroxide]] (potash lye), are softer or often liquid. Historically, potassium hydroxide was extracted from the ashes of [[bracken]] or other plants. Lithium soaps also tend to be hard. These are used exclusively in [[Grease (lubricant)|greases]].

For making toilet soaps, [[triglyceride]]s (oils and fats) are derived from coconut, olive, or palm oils, as well as [[tallow]].<ref name="Ullmann">David J. Anneken, Sabine Both, Ralf Christoph, Georg Fieg, Udo Steinberner, Alfred Westfechtel "Fatty Acids" in Ullmann's ''Encyclopedia of Industrial Chemistry'' 2006, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a10_245.pub2}}.</ref> Triglyceride is the chemical name for the [[Ester|triesters]] of fatty acids and [[glycerin]]. Tallow, ''i.e.,'' [[Rendering (animal products)|rendered]] fat, is the most available triglyceride from animals. Each species offers quite different fatty acid content, resulting in soaps of distinct feel. The seed oils give softer but milder soaps. Soap made from pure [[olive oil]], sometimes called [[Castile soap]] or [[Marseille soap]], is reputed for its particular mildness. The term "Castile" is also sometimes applied to soaps from a mixture of oils with a high percentage of olive oil.

{| class="wikitable" |
|+ Fatty acid content of various fats used for soapmaking
|-
|+
! !! [[Lauric acid]]!! [[Myristic acid]]!! [[Palmitic acid]]!! [[Stearic acid]]!! [[Oleic acid]]!! [[Linoleic acid]]!! [[Linolenic acid]]
|-
! '''''fats'''''!! C<sub>12</sub> saturated!!C<sub>14</sub> saturated!!C<sub>16</sub> saturated!!C<sub>18</sub> saturated!!C<sub>18</sub> monounsaturated!!C<sub>18</sub> diunsaturated!! C<sub>18</sub> triunsaturated
|-
| [[Tallow]] || style="text-align:right;"| 0 || style="text-align:right;"| 4 || style="text-align:right;"| 28 || style="text-align:right;"| 23 || style="text-align:right;"| 35|| style="text-align:right;"| 2|| style="text-align:right;"| 1
|-
| [[Coconut oil]] || style="text-align:right;"| 48 || style="text-align:right;"| 18 || style="text-align:right;"| 9 || style="text-align:right;"| 3 || style="text-align:right;"| 7|| style="text-align:right;"| 2|| style="text-align:right;"|0
|-
| [[Palm kernel oil]] || style="text-align:right;"| 46 || style="text-align:right;"| 16 || style="text-align:right;"| 8 || style="text-align:right;"| 3 || style="text-align:right;"| 12|| style="text-align:right;"| 2|| style="text-align:right;"|0
|-
| [[Palm oil]] || style="text-align:right;"| 0 || style="text-align:right;"| 1 || style="text-align:right;"| 44 || style="text-align:right;"| 4 || style="text-align:right;"| 37 || style="text-align:right;"| 9|| style="text-align:right;"|0
|-
| [[Laurus nobilis|Laurel oil]] || style="text-align:right;"| 54 || style="text-align:right;"| 0 || style="text-align:right;"| 0 || style="text-align:right;"| 0|| style="text-align:right;"| 15|| style="text-align:right;"| 17|| style="text-align:right;"|0
|-
| [[Olive oil]] || style="text-align:right;"| 0 || style="text-align:right;"| 0 || style="text-align:right;"| 11 || style="text-align:right;"| 2 || style="text-align:right;"| 78|| style="text-align:right;"| 10|| style="text-align:right;"|0
|-
| [[Canola oil]] || style="text-align:right;"| 0 || style="text-align:right;"| 1 || style="text-align:right;"| 3 || style="text-align:right;"| 2 || style="text-align:right;"| 58|| style="text-align:right;"| 9|| style="text-align:right;"|23
|}
{{anchor|Soapmaking|Soap-making}}