Generally cold process soap making is straightforward and if you strictly follow the recipes and instructions you should not get any problems. However even the professionals may have batches that go wrong and here are some troubleshooting tips and example of what can happen and how to solve it.
Cold Process Soap Making – Troubleshooting Tips
PROBLEM 1
No Trace
CAUSE
Recipes with thin liquid oils can cause soap to take longer to come to trace. Castile bars can do this. Or you could have added too much water and not enough lye. Or your temperatures are too cold for a good chemical reaction.
SOLUTION
Make sure your temperatures are right. Watch for light trace. You should not have to blend for an hour. Did you add the lye water? Your batter may be very thin, but if you’ve really emulsified the oils with the water, use a good light to look for a slight trail left behind when soap is drizzled over the top.
PROBLEM 2
Coming to trace too fast
CAUSE
Higher temperatures, using a stick blender, and adding certain ingredients can all cause soap to come to trace quickly.
SOLUTION
When using honey and a lot of other hard fats and butters, watch your batter carefully. Don’t use a stick blender if you want to have more time before it sets.
PROBLEM 3
Seizing in the pot
CAUSE
Seizing can occur when the soap comes to trace too quickly or the temperature cools at the same time the soap starts to come to trace, solidifying the oils.
SOLUTION
Scoop as much as you can into the mold. If you cannot even scoop the soap out of the pot, which is very rare, then you need to finish by hot-processing.
PROBLEM 4
Hard, chalky soap that crumbles when you try to cut it
CAUSE
Your recipe has too much lye.
SOLUTION
Measure your lye carefully every time! If this happens, save it by hand-milling (see here ) and add a tablespoon or two of water.
PROBLEM 5
Liquid oozing from soap
CAUSE
You may have had false trace, where the oils were not fully emulsified but cooled and hardened instead of actually reaching trace.
SOLUTION
Save by hand-milling.
PROBLEM 6
Gel-like soap with wrinkled top
CAUSE
Your soap overheated.
SOLUTION
If it is hard, it’s still fine to use. If you don’t like the wrinkled top, shave it with a potato peeler. If it’s soft, it may need to be hot-processed or allowed to cure longer.
PROBLEM 7
Soap begins to crack or bubble up in the middle
CAUSE
This usually occurs only when soap with extra sugars from juices, milks, or alcohol become overheated.
SOLUTION
All recipes with juice, milk, or alcohol have steps to ensure that this doesn’t happen. Start with alcohol boiled off and milk, juices, or alcohols frozen to a slush. If this still happens, carefully uncover and place the mixture in the refrigerator if possible.
PROBLEM 8
White powder on top of soap
CAUSE
This is known as soap ash and is purely cosmetic.
SOLUTION
The only sure way to avoid soap ash is to carefully place parchment paper directly on the top surface of your soap after pouring. This isn’t possible in molds with inserts and can ruin some designs; in these cases try to keep your soap well insulated. If you want to get rid of it, simply shave it off with a potato peeler or rub very gently while you rinse the bar. Don’t touch as it dries to avoid fingerprints.
PROBLEM 8
Dark center and light edges
CAUSE
This is known as a partial gel. If too much heat is lost around the edges of the mold, the outer edges of the soap will not gel. It is purely cosmetic.
SOLUTION
There is no fix for a partial gel. Just make sure that you insulate better the next time you use that recipe. If this happens often, you may want to consider placing newly poured soap in a 170°F oven until fully gelled. The entire batch will look dark. Then remove and allow to cool.
PROBLEM 8
Crooked soap
CAUSE
Curing on an uneven surface.
SOLUTION
Get a level or use an app on your phone to see if the location that you want your soap to rest is level. If your floor happens to be very uneven in that spot, your soap will come out lopsided.
PROBLEM 9
Soap remains soft, even after days in the mold
CAUSE
You probably didn’t add enough lye.
SOLUTION
You can still use this batch for personal use. It will continue to harden over a few weeks but will not be a long-lasting bar. You can turn this soap into a moisturizing hand soap: Shave 4 bars with a potato peeler and add them to a gallon of water, then heat lightly until melted.
PROBLEM 10
Soap separating in the mold
CAUSE
It wasn’t properly blended, so the oils and water did not fully emulsify.
SOLUTION
Scrape the soap back into the pot and blend until emulsified, then return the soap to the mold.
PROBLEM 11
Soap has colored spots
CAUSE
Fresh herbs or teas were not prepared properly or the oils in the soap are going bad.
SOLUTION
Dried herbs are better than fresh, because teas and herbs can bleed into the soap over time. This is why I suggest making tea before using the tea leaves. You can always incorporate the tea water into your soap as well. If the spots are orange or brown from oils going bad, there’s really nothing you can do. Always store soaps in a cool, dry location out of the sun.
