Lye and it's essential role in soap making

Lye and it's essential role in soap making

What is lye?

Lye is an alkali metal hydroxide, Sodium Hydroxide. It is often used as a drain cleaner because it creates heat to melt and dissolve grease, hair, soap, scum, and other drain clogging material.
AND for our job making Cold Process Soap, chemically speaking, you cannot make soap without lye. So how does such a harsh ingredient make mild and gentle soap bars? This is due to a process called saponification, or magic as I like to call it.
Lye is added to water, and reaches a very high temperature, once it's cooled to a particular temperature it gets added to heated oils of a similar temperature. Lye then causes the oils to saponify and here is the science part -
'Saponification is the process of making soap from alkali and fat (or oil). Vegetable oils and animal fats are fatty esters in the form of triglycerides. The alkali breaks the ester bond and releases the fatty acid salt and glycerol'
Once cured, the process of allowing saponification to complete and for water to evaporate out, there is no lye left in the soap, the chemical reaction changes the lye so it is no longer present - see, it's magic!

So why do we always keep a bottle of vinegar close by?

So why the vinegar? I'd guess all soap makers at some point have splashed themselves with a little lye mixture or got a grain on their skin, I know we have here, and it is a corrosive chemical it is extremly painful and burns badly, therefore we need an acid to neutralise the alkali, and vinegar stinks, but does the job! We always keep a bottle nearby, just in case!
All of our soap bars are made by cold process method and you can find our large selection on our website. Here is our gorgeous Milk Soap selection for you to browse.
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