Blue Aspen Originals

aspen leaf
Fine soaps hand crafted in small batches

Definitions and FAQ for Soapmaking


Borax: is a chemical sometimes added to soaps in areas of hard water to help soften the water and allow the soap to lather. Addition rate is small, usually 1 tablespoon for 20 ounces of water in the recipe or 3 lbs of oil.
Cold Process: is a soap making method where no additional heat is added during the process. The chemical heat from the saponification process (gel stage) is the only heat in this method causing saponification to take place over several weeks during its curing time. (see also Hot Process)
Cure: is the time cold process soap is allowed to sit before using, usually 4 weeks. This time allows cold process soap to slowly saponify and become less harsh. Also it allows the water to evaporate out creating a harder bar. Some soaps cure faster, others like castile soaps high in olive oil or shampoo soaps high in castor oil, can take several months to harden.
Gel Stage: is where the soap heats up from the chemical reaction of saponification. Some soapers feel their soaps are smoother and have a different feel if they do not go through gel stage. It will just take longer for the soap to saponify when no heat is involved in the making process.

gel stage An example of soap going through gel stage. It heats up and becomes translucient. Notice the corners where it hasn't heated up and changed yet.


Hot Process: is a soapmaking process where additional heat is added during the soap making process. The soap is heated up either in a microwave, oven or crockpot to quickly create soap. The additional heat helps to go through the saponification process much faster than the 4 weeks that cold process soap is allowed to cure. The additional heat helps the soap to form as well as remove much of the excess water so soap made this way is ready to use as soon as it has cooled. (see also Cold Process)
Saponification: This is a chemical reaction, fat or oil reacts with a strong base (sodium hydroxide or potassium hydroxide) to produce glycerin (glycerol) and soap. This process takes place over time in cold process soap because added heat is not used. Some batches of cold process soap will heat up and go through a gel stage, in this stage heat is created by the chemical reaction and causes saponification to happen in a shorter amount of time. Hot process methods of soapmaking add heat to finish the saponification and create soap in a very short amount of time.
Soap: The basic soap molecule is attracted to organic materials (skin oils and dirt) on one end of its chain and watery materials on the other end of its chain. Because water and oil do not mix you need soap to attract the dirt & oils and water to help wash it away. Soap is produced when a fatty acid is combined with a base (or aklali) in a process called saponification. The base splits the oil into two parts, a carbon chain & glycerin. Sodium or potassium then attaches to the carbon chain to produce soap. So to make soap you need fatty acids to create the carbon chain & glycerin (oils) and a base (lye). Much of what we call soap is actually detergent. Detergent is a synthetic blend of hydrocarbons derived from crude oil. Although early evidence of soap was found in clay cylinders dating back to about 2800 BC, detergents were first produced in the United States during the 1930s to eliminate the residual curd (soap scum) produced in hard water.

Stearic acid: is used at 2-3% as a thickener in lotions and creams, and at 1% to produce a hard bar of soap.Too much will make a brittle bar of soap that crumbles.
Superfatting: this concept is sometimes difficult for beginners to get a grasp of. Soap is a combination of oils and lye that go through the chemical process of saponification to make a new material, soap. If there was the exact amount of lye to saponify all the oils in your recipe, leaving no lye or oils in the end, you have 0% superfatting (also called 0% lye discount or 0% excess fat). If you made a soap that had more oils than the lye could saponify you would have a superfatted soap. If it was 1% superfatted that means 1% of your oils did not turn into soap. Ranges of superfatting between 1 and 4% are generally not recommended due to rounding of saponification values and variations of the oil. It has a chance of creating a harsh soap. Most soapmakers aim for a range between 5 and 8% (has 5-8% more oils than soap in the finished bar) because it is mild. If you superfat over 8% you run the risk of your soap becoming rancid and being too soft because of the high amounts of free oil left in the bar. The way to superfat is to calculate more oil into your recipe or to discount the lye for the amount of oils the recipe calls for.

Some soapmakers select a special oil to superfat with and add it in to the soap right before they pour it into the mold. The idea behind this is that once trace has been achieved most of the lye and oils have combined, leaving the special oil with no lye to react to it so more of its qualities are lent to the bar of soap. You do not have to superfat this way, just calculate your recipe to have 5% of the oils left over in the end.

The easiest way to figure out superfatting percentages is to use the MMS Lye Calculator Enter in the amounts of oils you want to use and it will compute a range of superfatting from 0-10%. Use the corresponding amount of lye the calculator gives you for the % superfatting you choose.


Tare:is when you put put your measuring container on the scale and reset the weight to zero so you do not weigh the container.
Trace: happens when lye-water mixture and oils are thorough mixed and start to react. It looks like pudding, ranging from thin to thick consistency. When stirring the spoon leave a "trace" or trail in the soap that takes a little time to fill back in.

soap tracehere the soap has traced, turned thick like pudding and coats the stick blender.