Sodium lactate in soap is commonly used to harden the resulting soap bar. There are many ways to affect the hardness of your bar, but sodium lactate is very popular with soap makers. At a usage rate of 1 teaspoon per pound of oils in your base soap making recipe, it is economical and a little batch can go a long way for you. Sodium lactate in soap is also very useful when using a hot process soap recipe, as it can be used to increase the liquidity of the soap before you start pouring. Made from the fermentation of sugars naturally occurring in beets and corn, sodium lactate is the sodium salt of lactic acid.
Sodium lactate is also the liquid salt of lactic acid. It’s generally added to cooled lye water at a rate of 1 teaspoon per pound of oils. It hardens up your bar, and really helps extend the life in the shower.
The hardest part of making soap is often waiting to unmold it to see the finished product. Luckily, there is an easy way to cut down the wait time. Sodium lactate is a liquid salt that can be added to cooled lye water in order to speed up unmolding time. Using sodium lactate produces harder, longer-lasting bars of cold process soap.
Naturally a liquid product, sodium lactate is also available in powder form. Sodium lactate is commonly used in food products as a preservative. It’s also an extremely effective humectant, helping to strengthen the skin moisture barrier.
When making cold process soap, sodium lactate is added to cooled lye water. Lye water can reach temperatures up to 200°F. For soap making, it’s recommended to wait until the lye water has reached temperatures of 130°F or below. Once the lye has reached optimal soap making temperatures, the sodium lactate can be added.
Simply measure out the sodium lactate, and stir into the cool lye water. Be careful not to use too much; using too much sodium lactate will result in a hard, crumbly bar of soap.
Sodium lactate is especially useful when creating soap that is palm free, or contains a high amount of soft oils. Castile soap is notoriously soft and requires a long cure time. Using sodium lactate makes these soap easier to unmold, which speeds up the drying process.
Sodium lactate can also be used in lotions to create a thicker, more hydrating product. In some recipes, sodium lactate is used to create a creamier texture. The humectant properties of sodium lactate keeps skin moisturized longer.
In addition to hydration, sodium lactate cuts down on the stickiness sometimes found in lotion with a high glycerin content. In lotion recipes, a little sodium lactate goes a long way. Typically, the sodium lactate is used at 1-3% of the total lotion recipe.
How to Make Sodium Lactate at Home
Sodium Lactate is produced through the fermentation of sugar, an alpha hydroxy acid that occurs everywhere in nature. It has a 60% concentration in water, and is the sodium salt of natural L(+)-Lactic Acid,
Sodium Lactate is one of the Natural Moisturizing Factor (NMF) constituent of skin, and it is required in the maintenance of natural hydration. Sodium Lactate is a superior moisturizer, increasing the moisture content of skin by up to 84%. When compared to other commonly used moisturizers, it’s water holding capacity is second only to Sodium Hyaluronate (Hyaluronic Acid).
Sodium Lactate is an edible material that has been used for decades in the meat-packing industry because it effectively forces cells to hold water.
Sodium lactate is most often made by the fermentation of a sugar, which can come from corn or beets, to produce lactic acid. After the fermentation, lactic acid is produced and this is then neutralized to create sodium lactate.
Although sodium lactate can be prepared by the fermentation of milk or whey protein, but that is not often the case and the resultant fermentation product will not contain any residual milk protein.
Sodium lactate powder is dusty and you only need tiny amounts, so it is recommended to make a 50% or 60% masterbatch SL solution and using this liquid when making soap rather than the powder.
For a 60% masterbatch that is comparable to the commercial SL liquid, mix 6 parts sodium lactate powder with 4 parts distilled water by weight.
To make a 50% masterbatch, mix 1 part SL powder with 1 part distilled water by weight.
Stir until the powder is dissolved. Store the solution in a tightly closed container at room temperature.
Sodium lactate is also formed when you add a source of lactic acid to your recipe. Lactic acid is found in fermented dairy products such as yogurt, buttermilk, and kefir.