The warm-process method is, as you may guess, somewhere between the cold-
process and hot-process methods. Instead of insulating the soap with blankets while it
is in the molding stage, or boiling it to achieve faster saponification, the filled soap
molds are heated in an oven.
To begin oven hot-process (OHP) soap, you can use any hot- or cold-process soap
recipe. Turn your oven to its lowest possible setting – no more than 170°F. As with
cold-process soap, mix the lye and water, heat the fats, and combine when they are at
approximately the same temperature. Stir the batter until it achieves a medium to
thick trace. Be sure to use a large pot, such as a stainless-steel stockpot, so that the
soap mix doesn’t boil over in the oven. If it does, it’s messy, but not a huge problem;
the soap will smoke and smell bad, but it shouldn’t catch fire. Take out the soap,
clean up the mess, and continue cooking it. (The pause in cooking will not cause any
problems with the soap, for this method.)
At this point, place the mixture in the oven, and “cook” it at 160°F for
approximately 10 to 20 minutes. (The exact cook time will vary, depending on your
batch size, and oven.) Turn off the heat, and leave the pot in the oven, with the door
closed, for approximately one hour. After this time has passed, test the soap’s pH to
see if it has completely saponified. If not, put the soap back in the oven for 15
minutes, and test again. If it is ready, add your essential oils or other additives, stir
the batter thoroughly, and pour it into the molds. Once the mold has cooled, the soap
can be removed and cut. Though it is completely saponified at this point, the bars
still need to cure and harden for 2-3 days before use, as with hot-process or rebatched
soap.
FULL-BOILED METHOD
This method is typically favored by commercial soap-makers. All ingredients are
added at once, in a large container, and heated to cause saponification. Glycerin is a
by-product created via this method. The glycerin is typically removed by commercial
soap-makers, and sold; however, your soap, with the glycerin still in it, will be
naturally more moisturizing and skin-conditioning than commercial bars.
TRANSPARENT METHOD
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