Soapmaking Methods

There are a number of ways of making soap.  Here are the main methods.

Cold Process

This is how Amore Soap is made.  It’s the most direct way to transform oils into soap.

The first step is to mix lye crystals with water.  It’s best to do this first because the chemical reaction that happens creates a lot of heat.  It also releases harsh fumes, so you need to work in a well-ventilated area, and use some kind of respiratory protection.  Once the lye solution is mixed, it can be cooled in a container of cold water.

The next step is measuring the oils.  I measure the shea butter and coconut oil first because they’re solid at room temperature, and must be melted.  Then I measure the olive and canola oils and add them to the pot.  I make sure the whole mixture is at my mixing temperature of just under 100°F.

Once the lye solution has cooled, and the oils have heated, I pour the lye solution into the oils and turn on my hand blender.  As I mix the soap, the colour turns creamy, and it begins to thicken.  When it reaches a certain consistency, I pour it into my box mold to cure overnight.

The next morning, I remove the soap from the box mold and cut it into individual bars.  These bars sit on the shelf for a month until they have fully cured, and are ready to package and ship.

Hot Process

Hot process soapmaking is similar to cold process until the lye solution is mixed with the oils.  At that point, instead of pouring it immediately, the mixture is heated until it has the consistency of mashed potatoes, then scooped into the mold.

Melt and Pour

Melt and Pour soapmaking kits are ideal for those who want to make fancy scented soaps without worrying about exact oil quantities or the hazards of mixing lye.

The kits consist of a blend of fats or oils that have already been saponified.  Essentially, these kits are already soap.  The soapmaker simply melts the contents of the kit in a double-boiler or similar apparatus, then adds colours and fragrance ingredients to customize the soap.  After mixing, the soap is poured into a mold for cutting, or into individual molds for decorative soaps.

The advantage of the melt and pour method is that it’s less complicated than the other methods.  The disadvantage is that you have little control over the mixture of fats and oils in your soap.

Commercial-Scale Soapmaking

Commercial-scale soapmaking follows the same general pattern as the other methods, but naturally on a much larger scale.

According to the description I’ve read, it’s not a batch process, but a continuous one.  Fats and oils are added to a large reaction vessel along with lye solution.  The vessel is stirred constantly.  The ingredients tend to be more thoroughly reacted at the bottom of the vat because that’s where the off-take pipe conveys the new soap to the next part of the process.  Because of the size of the vat, the temperature of the soap mixture is closer to hot process than cold process.

A screw conveyor takes the soap to another process area where the glycerin is removed and other ingredients are added.  After this stage, the soap goes straight into molds.  After a relatively short time in the molds, the bars of soap are popped out and conveyed to the packaging section of the factory where they are wrapped, then boxed.  From there, they sit in a warehouse waiting to be distributed to stores.

Unlike handmade soap, which is monitored daily as it cures, most of the curing takes place from the time the packaged bars enter the warehouse.  A few quality control samples are opened to ensure consistent quality.  By the time the soap has reached the store, it is fully cured.

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