While the chemical reaction that creates soap is always the same, different types of soaps can be made
by different methods, all still relying upon that basic chemical reaction that occurs (see
How is Soap Made for more information on the actual processes used.
Cold process soapmaking is the method most often used by soapmakers who make soap from scratch.
It's called "cold" process because no additional heat is added during the soapmaking process, however the process
itself does generate heat.
Handcrafted soapmakers generally pride themselves on their unique recipes, developed to create their
signature soaps. Soap ingredients
are usually food-quality, natural ingredients starting with a variety of
vegetable oils such as olive, coconut, or palm, or purified tallow or lard. To these the soapmaker
might add specialized oils, nut butters or seed extracts to bring the desired qualities to the
Soaps produced via the cold process method are opaque and usually have a creamy feel to the bar.
Without any additives that change the color, the soap ranges from white-white to creamy-tan,
depending on the oils used in making the soap.
The feel of the lather varies, also dependent upon the oils used to make the soap. The lather can range
from tiny, very slippery, long-lasting bubbles (as with pure olive oil soap), to big, fluffy, short-lived
bubbles (as with pure coconut oil soap).
The hardness of the bar is determined by the selection of oils, the amount of water
used and how long the soap was dried. Cold process soaps will continue
to get harder as they age because additional water evaporates out of the soap.
Most cold process soaps are made with a combination of oils, in a recipe developed by the soapmaker
to create a good lather and hard bar, as well as to provide benefits with additional ingredients.
In hot process soapmaking, additional heat is applied to the soap mixture. The chemical reaction is the
same, but occurs faster than in cold process soapmaking. Because of the additional heat, the
finished soap bar tends to feel smoother to the touch. The hardness of the bar again depends on the selection of
oils, amount of water used in the process and length of time allowed for water to evaporate out
of the finished bar.
As with cold process soap, the hot process soap is opaque and ranges from white-white to creamy-tan
depending on the oils used, although clear soaps can be produced (see "Transparent Soap" below).
The type and quality of the lather and other benefits of the soap are determined by the oils and
other ingredients selected to make the soap.
Liquid soap is usually made with the hot process method, The soap ends up liquid because a different
type of lye is used (potassium hydroxide instead of sodium hydroxide) and more water is added. Liquid
soaps are typically off-white to amber colored, depending on the oils used. Most liquid soaps are
clear or mostly clear.
As a side note, most commercial "liquid soap" or "soft soap" is not true soap; it is made with
Transparent Soap is made by the hot process method, with some added ingredients and steps in the
process to make the soap clear. There are a some highly-skilled handcrafted soapmakers who produce
transparent soap from scratch, but a majority of handcrafted transparent soaps on the market are
produced from a ready-made soap base.
Glycerin is a by-product of the chemical reaction of the soapmaking process. In commercial soaps, the
glycerin is typically removed, purified and then sold for other uses including food, cosmetics, various industrial
production and explosive manufacturing. The method for removing the glycerin from soap is complex and
requires considerable equipment and skill. As a result, all handcrafted soaps made from scratch retain
the glycerin (and all it's beneficial properties) and so are all technically "glycerin soap".
Subsequently, the term "glycerin soap" is somewhat of a misnomer. Most people using the
term "glycerin soap" are, in fact, referring to transparent soap.
Rather than make soap from scratch, some soapmakers choose to purchase ready-made soap bases
which they melt into liquid form, add color, scent or other ingredients and then poured into molds.
The benefit to using a ready-made soap base is that the chemical reaction which produces soap has
already occurred, making it easier for the handcrafter to craft elegantly and uniquely shaped and colored
soaps. Many of the artistic presentations of handcrafted soap can only be created with a ready-made soap
There are a number of different ready-made soap bases available on the market. Some are "true soap" (made via the chemical
reaction referred to above) and some contain synthetic detergents as all or a portion of its ingredients.
Images shown above are randomly selected from the Soap Gallery
and are not necessarily representative of the type of soap they are displayed next to.