Ever find yourself scrub-a-dub-dubbing
in the bath or shower, musing upon the origin of intelligent
life in the universe and how they make soap? Well, as far
as the first question goes, the jury is still out on whether
there is indeed intelligent life in the universe. But we
can certainly answer your question about soapmaking.
Soap base is made by mixing fat with
an alkali, a process called saponification. In the
old days soapmakers used the ashes of plants like the soapwort
and barilla for the alkali. But ever since Nicolas Leblanc
figured out how to synthesize the active ingredient, sodium
hydroxide (a.k.a. lye), in late 18th c. France,
thats what everyones been using.
When it comes to which fat to use, however,
there are still lots of options: saturated, unsaturated,
ploy, mono, animal, vegetable.
Most soaps are made from a tallow base
(thats right, animal fat
whence comes the expression soap
rendering). It doesnt matter how many flowers
are on the package, or even how transparent the bar is,
unless it specifically says "vegetable base" its
probably tallow.
Why tallow? Its cheap. It makes
a great base for soap. And people have been using it for
soap ever since Phoenicians started boiling up goat fat
with wood ashes about 2500 years ago. (The first solid
soap bar was made in the Middle East around the 8th century.)
We have a preference, aesthetic and
otherwise, for soaps with a vegetable-base, which tend
to be made with a blend of 80% palm oil and 20% coconut
oil, but can also contain olive and/or other vegetable
oils. The base for true Castile soaps, for example,
is primarily olive oil, as is the base of our Jardin
dOlivier soap.
How about gylcerine soaps? Well
heres a little-known fact: you dont have to
add glycerine to make a glycerine soap base. You just have
to leave it in! When you mix fat with lye, the reaction
creates about 93% soap and 7% glycerine. Usually all but
about 1/2% of that glycerine is removed. In glycerine soap,
its left in (and, occasionally, more is added to
bring that level up to around 10%). Also, just because
the soap is clear doesnt mean it has a vegetable
base. The only glycerine soaps we carry are in the Essence line
from France, and they do have a 100% vegetable base.
Whats a superfatted soap?
Once where theyve added additional oil or fat (often
lanolin) to the base after saponification. How about Castile
soap? A soap with a base thats primarily olive oil
and made in the Castile area of Spain. (Unless, of course,
its just a soap word with the word "Castile" on
the label).
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