How Long Does It Take For Melt And Pour Soap Base To Cure?
What is Melt and Pour Soap Base?
Melt and pour soap base is a premade soap base that soapmakers can use to create handmade soap without having to make soap from scratch through hot or cold process soapmaking. It is manufactured by large soapmaking companies and comes in a solid block form. The soap base contains ingredients like water, oils, sodium hydroxide lye, and emulsifiers needed to make soap. The key difference with melt and pour soap base is that saponification – the chemical process of soapmaking where oils and lye react to create soap – has already occurred.
This allows hobby soapmakers and small businesses to skip the more complex soapmaking steps of working with lye and managing the saponification process. Melt and pour soap base just needs to be melted, mixed with additives like fragrances or colors, and poured into molds. The soap then solidifies upon cooling and can be used after curing.
Why Does Melt and Pour Soap Need to Cure?
Melt and pour soap needs to cure to allow the chemical reaction called saponification to fully complete. Saponification is the process where the alkali and fatty acids combine to form soap, releasing glycerin as a byproduct. Although the initial saponification reaction happens when the ingredients are melted and mixed together, it takes time for this reaction to fully finish [1].
Allowing melt and pour soap to properly cure results in a harder, longer lasting bar of soap. Curing allows time for excess moisture to evaporate, resulting in a firmer bar. It also allows the structure of the soap molecules to rearrange into a tighter lattice, increasing hardness. Properly cured soap will last longer in the shower without turning soft or mushy [2]. Finally, curing allows time for any additives like fragrances, colors, and botanicals to fully blend and interact with the soap base.
Optimal Curing Time
The optimal curing time for melt and pour soap is generally considered to be 1-2 weeks (source). This allows enough time for the soap to harden completely and for any excess moisture to evaporate. Melt and pour soap is technically ready to use once it has cooled and hardened in the mold, which takes 2-4 hours (source). However, allowing it to cure for 1-2 weeks helps improve the quality and longevity of the soap.
There are a few key factors that affect curing time:
- The thickness and shape of the soap – Thicker bars or intricate molds take longer to cure.
- Additives – Ingredients like milk, honey, or fruit purees add moisture and extend cure time.
- Environment – Warmer, drier conditions allow soap to cure faster than cool, humid conditions.
Testing the soap periodically by feeling for moisture and firmness is the best way to determine if it is fully cured. 1-2 weeks allows time for moisture to evaporate so the bars last longer.
Stages of Curing
Melt and pour soap goes through several stages during the curing process:
Initial cooling and hardening: Once poured into molds, the soap begins to harden as it cools. The initial cooling happens quite fast, with the soap being solid enough to remove from molds within 4-6 hours according to New Directions Aromatics.[1]
Further hardening over hours/days: Though solid after several hours, the soap continues to harden and cure over the next 1-2 days. During this time, melt and pour soap may still feel slightly soft or flexible.
Extended curing over weeks: While melt and pour soap is safe to use after 1-2 days, an additional 1-4 weeks of curing allows moisture to evaporate, making the bars harder. Botanie Soap Company notes this extended curing period improves the soap’s lather and longevity.[2]
So in summary, melt and pour soap goes through progressive stages of cooling, hardening, and curing over hours, days, and weeks after being poured and molded.
[1] https://www.newdirectionsaromatics.com/blog/products/all-about-melt-and-pour-soap-bases.html
[2] https://botaniesoap.com/blogs/misc/melt-and-pour-soap
Testing for Cure
Once the soap has cured for the recommended time, there are a few ways to test if it is fully cured before using it or selling it:
Look and Feel: A properly cured soap should have a smooth, hard surface with no oily residues. Check the sides and bottom of the soap as well. If it still feels soft, sticky or greasy, it needs more time to cure.
Testing for Hardness: Press into the soap firmly with your finger – a cured soap should spring back without leaving an indentation. Try scratching the surface with your fingernail, it should be difficult to make a mark on fully cured soap. These tests indicate a hard, durable bar.[1]
Testing Longevity: A cured melt and pour soap should last at least 4-6 weeks with regular use if properly formulated. Let the soap sit for a week after curing, then use it regularly. Check for issues like cracking, breaking or dissolving which can indicate insufficient curing. A properly cured soap will last a month or more under normal conditions.
Tips for Proper Curing
Proper curing is essential for melt and pour soap to achieve its best quality. Here are some tips for optimal curing:
Cool the soap completely after pouring and before removing from molds. Letting it sit at room temperature for 4-6 hours is ideal, as cooling too quickly can cause cracking or discoloration (Botanie Soap).
Store cured soap in a cool, dry place away from light and heat. Excess moisture and warmth can cause sweating or partial melting (New Directions Aromatics).
Avoid gel phase during curing. Insulating the soap as it cools encourages gel phase, which is not necessary for melt and pour soap. Allow air circulation instead (The Witty Gritty Life).
Using Cured Soap
Once melt and pour soap has fully cured, it is safe to use. The curing process allows for excess moisture to evaporate so the bars harden and last longer. Using soap before it has cured can lead to issues like sweating, dripping, and dissolving too quickly in water.
Some benefits of allowing melt and pour soap to properly cure include:
- Harder, longer lasting bars
- Better lather and sudsing
- More distinguished scent
- Smoother texture
- Bars that hold shape better
- More clarity in transparent soaps
- Stabilized color
- Prevents evaporating moisture and damage
Once soap has cured, it is safe to handle and use for bathing, hand washing, and more. The harder bars will last longer than uncured soap, providing a better value. The stabilized scent and colors also make for a more appealing bar. Overall, allowing proper cure time results in higher quality, handcrafted melt and pour soap bars. For tips on curing to maximize these benefits, check out this helpful video: How to Cure Melt and Pour Soap
Troubleshooting
Even when following best practices, problems can arise during the melt and pour soap curing process. Here are some common issues and how to fix them:
Signs of Undercured Soap
If soap hasn’t cured completely, you may notice that it feels soft, sticky, or oily to the touch. The surface may also look wet or translucent. Undercured soap is more prone to melting, sweating, and developing dough-like textures when exposed to moisture. Sweating, which is beads of oil appearing on the surface, indicates the soap contains too much unreacted oils. According to Botanie Soap, undercured soaps don’t produce as much lather either.
Fixing Improperly Cured Soap
To fix undercured melt and pour soap, allow it to cure longer. Place it in a dry, well-ventilated area out of direct sunlight for at least 48 more hours. Rewrap the soap in fresh packaging as well. This gives any remaining moisture and oils more time to react and harden. According to Bulk Apothecary, you can also gently remelt poorly cured soap and pour it into molds to cure again.
Curing Soap with Additives
When adding colors, scents, oils, or other ingredients to melt and pour soap, it will take longer for the soap to fully cure. The additives introduce more moisture into the soap base, so it needs more time to evaporate.
Here are some guidelines for curing times with additives:
- Colored soap – Cure for 4-6 weeks
- Lightly scented soap (2% fragrance oil or less) – Cure for 2-4 weeks
- Heavily scented soap (more than 2% fragrance oil) – Cure for 4-6 weeks
- Soap with additives like oils, butters, milk, aloe vera – Cure for 3-5 weeks
When adding more moisture to the soap base, it’s important to store the soap in a well-ventilated area during curing. This allows the excess moisture to evaporate properly. Avoid curing boxes or closed containers. Fanning the soap periodically can also help speed up evaporation.
Test cured soap with additives carefully by sniffing for scent dissipation and checking for tackiness on the surface before using. If any moisture remains, allow for more curing time.
Following proper curing guidelines will ensure your creative soaps retain their scent, color, and skin benefits when used.
FAQs
Here are answers to some frequently asked questions about curing melt and pour soap base:
Does melt and pour soap need to cure?
Yes, melt and pour soap does require some curing time. Unlike cold process soap, melt and pour soap hardens quickly and is ready to use more quickly. However, allowing it to cure for at least 24-48 hours will help the soap last longer and perform better. Curing allows excess moisture to evaporate.
How long does melt and pour soap take to cure?
On average, melt and pour soap takes 1-2 days to fully cure. Smaller bars or pieces may only need 24 hours. Larger bars, loafs, or embeds may require closer to 48 hours of curing time.[1]
Does curing melt and pour soap make a difference?
Yes, curing creates a harder bar of soap that will last longer in use. It also allows the scent to stabilize and evenly distribute through the soap. Skipping the curing step can result in sticky soap that falls apart easily.
How can you tell when melt and pour soap is cured?
Melt and pour soap is fully cured when it is completely hardened and not sticky to the touch. There should be no moist spots. The color should appear evenly distributed. And added scents will smell stronger and more uniform through the entire bar.
Should melt and pour soap be cured in the fridge?
Curing melt and pour soap in the refrigerator can help it harden faster initially. However, it is not required. Curing at room temperature between 60-85°F is recommended for 1-2 days to complete the curing process.[2]
