Cold Process vs. Hot Process Soap (2024)

FAQs

Which is better cold process soap or hot process soap? ›

The benefits of natural soap making ingredients like coconut oil, shea butter and olive oil can lessen through the heating process in hot process soap techniques; however, the cold process method ensures these natural ingredients are better preserved.

If the lye is extremely hot, it can cause the saponification process to speed up dramatically. This is problematic if the soap design involves lots of layers, swirls or other complex techniques.

Melt and Pour Soapmaking

Commonly referred to as MP, melt and pour soap making is probably the easiest way to get started with soapmaking. It's as simple as buying a commercial premade base of soap, melting it down, adding in your goodies (like scent, color, botanicals, and more), and letting it set up.

Yes, cold-processed soaps are better for skin because they contain nourishing natural ingredients. The benefits of our plant-based ingredient are preserved by allowing them to cure naturally without heat. Plus, cold-processed soaps made with healthy fats are ultra-hydrating.

Waiting is one of the hardest parts of soap making. Cutting it into bars and seeing the design for the first time is such an amazing feeling. However, cutting too early can lead to dents and drag marks. Patience is best when it comes to unmolding soap.

Rebatching soap, remilling soap, or remelting soap, is the process of taking previously made cold process soap, grating it, melting it down, adding other ingredients if desired, and then recasting it into molds.

Chances are that hard water is making this daily routine a painful chore. Hard water minerals such as calcium and magnesium react negatively with the ingredients in your products. As a result, you don't get the rich lather you desire and may feel the need to use more product (which quickly becomes expensive).

The lye and oil mixture in hot process soaps makes them easy to nourish the skin. Hot process soap detoxifies, nourishes, moisturizes, and hydrates your skin as needed. In addition to providing moisturizing benefits, handmade soap produces a rich luxurious lather.

Can you overcook hot process soap? ›

Watching the soap gel along the outside of the crockpot will really help you with hot process soapmaking by being able to identify the stages. Don't stress about whether the soap is completely cooked before taking out of the crock! It will finish cooking in the mold and overcooked soap is a lot like overcooked chicken.

Handmade soap is always alkaline (cleansing ability) with a safe range pH between 10 to 8 to use on skin. Anything above pH 11 is too harsh for skin and will cause irritations. Anything below pH8 is not possible for handmade soap, no more cleansing power.

Glucose, fructose and sucrose not only up the lather but they also contain incredible antioxidant compound and antibacterial properties. It is important to keep in mind that the addition of sugar in your cold process soap recipe raises the temperature at which the batter moves from a liquid to a solid state.

The good news is you can use any cold process soap recipe as a hot process soap recipe. There are a few rules when making hot process soap. You want to use more water (if you normally discount) and you want to add additives that make your soap more fluid, such as yogurt, sodium lactate and sugar.

Cold process soap requires patience. It needs several days to harden in the mold. Then, it needs to cure for 4-6 weeks to allow excess water to evaporate. Curing creates a firmer bar that lasts longer in the shower.

A high quality soap made with care and attention will result in a soap that does not cause irritation, even to those with dermatological issues or extreme sensitivities. This requires quality oils, a formula that is as simple as possible, and high quality, skin-safe essential oils or fragrance oils.

Although handmade natural soaps usually get better with age, we recommend using our soaps within 12 months of purchase. Our scented soaps should be used within 3 months after removing them from the box. Although our soaps will not be "spoiled" after that time, you may notice some changes as natural soap ages.

Soap is the Result of Saponification

At the heart of all cold process soap recipes are two main ingredients: oil and lye, also known by its chemical name sodium hydroxide. Your soap-making recipe will, through a simple but controlled process, chemically bond these two ingredients into a new compound – soap!

Store the bars in a dry, cool place until you're ready to use them. Avoid the fridge - that can cause glycerin dew or make the soap brittle.

Any soap can be made with just one oil, but the only ones we recommend using up to 100% are olive oil or coconut oil. The others can feel too sticky, too hard, etc. Most recipes are a combination of hard and soft oils. You can substitute oils in your cold process recipe.

What is the best pH for cold process soap? ›

Cold process soap is naturally alkaline with a pH of around 9-10. This pH helps to gently clean the skin. Sodium hydroxide lye has a pH of about 14, putting it at the very top of the pH scale. When too much lye is used in the soap, the pH level will rise from the normal level of 9-10, and can become closer to 11-14.

Rebatch soap doesn't require a 4-6 week cure time like cold process soap does. But allowing the bars to cure for about 2 weeks will ensure extra moisture evaporates, creating a harder and longer-lasting bar.

After the soap is made, it takes about 24 to 48 hours until it is un-molded and cut. Cut soap 36 hours after it was made. Once the bars are un-moulded, sliced and set on the shelves (racks), the curing period starts. The place where the soap is cured needs to be an airy, out of direct sunlight, and a dark place.

If your soap crumbles when cutting or appears dry and powdery, it is likely that the soap is too lye-heavy. An abundance of lye in your recipe will be left without an oil to saponify with, thus showing up as free radical particles.

When making cold process soap, beware of false trace. False trace occurs when soap batter appears to be a thick consistency, but the oils and butters have not saponified. Perhaps the most common cause of false trace is using solid oils or butters at too cool of a temperature.

Soft, squishy soap can be caused by several factors. One reason may be that not enough lye was used in the recipe. If the soap does not contain enough lye, the oils will not saponify. Another reason for soft soap is there was not enough hard oils or butters (such as coconut oil, palm oil or cocoa butter).

It is caused by the expansion and contraction of a bar as its moisture content changes. This movement causes fatigue in the surface of the bar, leading to the cracks that you can see on its surface.

Oils such as coconut and castor oil help create a bubbly, foamy rich lather. On the other hand, soaps made primarily with olive oil, such as Castile type soaps, will produce a rich and creamy rather than bubbly lather. The naturally retained glycerin in handmade soap also helps create a lovely lather.

Hot process soap is ready to unmold within 24 hours, and does not require the 4-6 week cure time. Personally, I still like to allow my hot process soaps to cure for about 2 weeks to allow excess water to evaporate and create a harder bar.

Do you stir hot process soap? ›

The most important things to remember about hot process soap making are to stick blend all the way to medium trace, then allow the soap to cook, stirring occasionally until the soap becomes consistently soft and fluid-like mashed potatoes.

For soap to sweat, water must be available in the surrounding air. The humectants in the product attract moisture from the air and droplets of water form on the surface of the soap, creating a visual and tactile experience to resemble that of sweat appearing on skin.

By simply adding a bit more water, or sodium lactate and/or yogurt to your already wonderful recipe, you can enhance your soap with swirling designs and patterns. Give it a try! Would you like to learn more about the Hot Process method? Check out our article, Hot Process Soapmaking for Beginners, for more insight.

After the cook

Mix it in gently but thoroughly. Leave the soap to cool and harden for at least twelve hours. Afterward, measure and cut the soap into bars of whatever size you'd like. Though hot process soap is fully saponified after the cook, you should cure it for a full four weeks (at least) before using it.

For hot process soap, we recommend 15-20g* of fragrance oil for every kilogram of fats/oils in your recipe. For melt and pour soaps, we recommend 10g* of fragrance for every kilogram of melt and pour soap base. For lotions, creams, balms, shampoos, bath gels, etc, we recommend between 1-3%* by weight.

Normal healthy skin has potential of hydrogen (pH) range of 5.4-5.9 and a normal bacterial flora. Use of soap with high pH causes an increase in skin pH, which in turn causes an increase in dehydrative effect, irritability and alteration in bacterial flora.

In typical cold-process or hot-process soaps made with NaOH, 0.77 grams of glycerin are created for every 1 gram of NaOH used to make the soap. (Or 0.77 ounces glycerin for every 1 ounce NaOH.)

In particular, honey is a natural humectant, which means it absorbs moisture from the air. Humectants are great for the skin, as they can help the skin retain moisture. Honey also contains antioxidants and natural sugars which can increase the lather of cold process soap.

Making cold process soap with salt is a fun and interesting process, but it does require a little know-how. Salt inhibits bubbles and creates a creamy, dense lather. To balance this, you can increase the amount of coconut oil in your recipe - some soapers even go up to 100%!

Glycerin is used as a humectant in soap products. In other words, glycerin helps to ensure that your skin will maintain its own moisture in order to protect it from damage caused by dryness. Instead of creating a barrier, humectants such as glycerin still allow your skin to breathe.

What is special about cold process soap? ›

In cold process soaps, the ingredients are not heated, which allows them to conserve their beneficial and natural properties. This type of soap is also less aggressive because of the surgras present. The skin retains its hydrolipidic film after having been washed, which gives it extra hydration and protection.

While cold process soap has many skin benefits, one downside is that cold process soap does not last as long in the shower as soap made from surfactants and detergents.

Since no outside heat is involved to cure the natural soaps made by cold processing, the all-natural quality of all the natural ingredients such as butter, fats, essential oils, and fragrances still are intact and preserved in their natural form throughout the process, from the beginning till the very moment that it ...

Most hot process soap will be fully cooled and ready to unmold and cut in about 24 hours. As with any bar of soap, the longer it sits, the harder and better it will be. Letting it sit for at least a week will really make a difference in the overall quality of your bar.