When will my soap be ready to try? How do I know when it is cured? Is it soap yet?
When I embarked on my very first batch of cold process soap, two of these questions came to
mind as I melted the oils, added lye water, mixed and poured the batch into the prepared mold.
The first was, “When will this become soap?” Once the mixture hit trace, I knew it was soap, so
my question was answered—I thought.
After molding and wrapping the requisite towel around the newly born soap, I dreamed of
using it. As I consulted books and early online soaping groups, the consensus was that in six –
eight weeks my soap would be ready to take a shower with me. It never crossed my mind that I
might try it earlier.
Still, I wondered what constituted a fully cured bar and how I could know. I mean, six – eight
weeks? Did that mean that any point between six and eight weeks the soap was ready, or was I
looking for specific signs that the soap was cured? Surprisingly, I found no one who could clue
It took several years, but I am happy to say that I now know the answers to each of the original
Is it soap yet? Although trace is the hallmark sign of saponification, the mixture actually
becomes soap once the oils and lye water come together and emulsify, which occurs before
trace. Soapmakers who want as much time as possible to create designs quit mixing at this
point. Whether you choose to wait until trace or stop at emulsification is entirely up to you, but
if more time to design is important, begin as soon as the oils and lye water combine and do not
When may I try the soap? Soapmakers are always eager to try their creations and may do so as
soon as no lye is present in the soap, but it is likely more harsh than a fully cured bar and some
report skin irritation at this point, so take care. Please be clear that this bar is for testing
purposes and personal use only. Do not give baby bars away or sell them at this point. The soap
is not cured.
How do I know when soap is cured? It was several years before I found an answer to my query,
but I learned that soap is cured when it stops losing weight.
Here is the procedure for curing and judging a cured soap: Make a batch sheet form or at least
an index card. Record the date the soap was created and the date it was ready to cut. On
cutting day, choose one bar and mark it somehow to weigh the same bar each time. Weigh the
bar carefully and record the date and weight. Repeat this procedure each week until the bar
weighs the same two weeks in a row. The soap is now sufficiently cured and ready to wrap.
Now, if you feel strongly that a longer cure is a better cure, by all means, cure longer. Soap does
indeed continue to dry out and become milder as it is affected by the acidity in the
Now you have it. Go forth and make soap!
Until next time, may your days be filled with bubbles and wax.
Beth Byrne for Making Soap, Cosmetics & Candles
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