Soapmaking: What is a water discount?

A water discount is a reduction in the amount of water needed to dissolve sodium hydroxide lye. When you use a water discount, the soap will harden faster because there is less water in its batter (the mixture that eventually becomes soap). You only use a water discount for cold process or hot process soaps that use lye. You don’t need a water discount for melt and pour soap because the oils are already saponified and the lye has been used up before you ever get the melt and pour container!

Advantages of a water discount:

  • Your soap will cure faster
  • Your soap will be harder (ideal for Castile soap)
  • The soap can be taken out of the mold more easily
  • The mold will be easier to clean (less residue = less cleaning of the little corners of your molds is required – a constant problem I’ve had with homemade cosmetics, especially my all-natural conditioner bar).
  • A water discount helps balance the recipe if you’re adding other ingredients that contain water such as if you are using milk (including breastmilk) or if you’ve mixed mica powder with water rather than alcohol before adding it to your soap.
  • If you want to force a strong gel phase for a specific soap design, a water discount is a great addition to the other things you can do such as using heat pads around your soap while it’s curing.

Disadvantages of a water discount:

  • Your soap batter will thicken (solidify) faster, making it harder to work with. If you’re doing a color effect such as a swirl, you will want your batter to reach trace (ideal thickness) then to solidify slowly, to give you time to make your desired effect.
  • It can also effect your colors by messing with the heat of the soap. The reaction between lye and oils (saponification) is an exothermic reaction — it gives out heat. And if it heats up too much, it will affect what the soap looks like. If you want to avoid gel phase (e.g. when making cold process breastmilk soap, you do NOT want it to get too hot or the milk will spoil before the soap is done), don’t water discount more than you need to for the extra liquid in the milk.

To calculate a water discount, you use a percentage:

The usual amount of water to lye is 70% water to 30% lye. That means you use 70ml of water for every 30g of lye.

Discounting the water by 10%, you would have 63ml of water to 30g of lye.

Discounting the water by 20%, you would have 56ml of water to 30g of lye (this is a heavy water discount).

You also need to factor in whether your recipe requires a superfat (leftover oil for more nourishing soap bars). In this case, you usually wouldn’t discount your water.

Stuck? The very best resource on calculating the amount of oils, water and lye for your recipe is the Brambleberry Lye Calculator (it also calculates fragrance, but beware in the EU some of the fragrance results are higher than permitted under EU law if you’re selling your soaps). This tool is phenomenal!

10 ways to get essential oils to be more intense in your soap (melt and pour and cold process)

So you’re probably looking for how to get your essential oils to be more intense in your soap. You might be making cold process soap or melt and pour soap. Maybe you’ve made some homemade soap with pure essential oils and it didn’t come out with a strong scent, or perhaps you’re planning your first homemade soap making project and are hoping to execute a perfect first-time soapmaking recipe.

Here, I’m going to go through ten ways to get essential oils to be more intense in your soap. These methods for increasing the scent of your soaps are all based on principles of chemistry. Essential oils are volatile compounds which means they evaporate easily. That’s actually why we love them! They wouldn’t smell so good if they weren’t made exactly the way they are by nature.

Getting a stronger essential oil fragrance in soapmaking is one area where melt and pour soap really outshines cold process, and is one of the reasons I prefer melt and pour soap. Secretly, I think a lot of soapmakers prefer melt and pour, but it’s more profitable for them to write about cold process because it takes more skill to make it (so there’s more to write about).

Essential oils do really well in melt and pour soap. Cold process soap tends to eat the fragrance. But these are not hard and fast rules. It took me several attempts to get lavender essential oil to show up in my melt and pour soap.

If you look at my infographic on essential oils in soap, you’ll see the results I got when I tried a range of essential oils in melt and pour soap. Lavender oil was particularly problematic in melt and pour, and I’ve written a separate article on this.

1. Have you used the correct amount of your pure essential oil in your soap?

This is the easiest fix! All handmade essential oil soaps require different quantities of essential oils to get the perfect fragrance. Bramble Berry’s Soap Queen blog has a fragrance calculator that can help you out. You can find it here.

2. Add a clay as this can hold the fragrance in the soap.

Typically, this works to intensify the scent of essential oils in cold process soap, but I found it made a noticeable difference to increasing the scent of melt and pour soap too. French clay, kaolin and bentonite are all great choices, but some of them will colour your soap so be sure if you plan to sell your soap that the colour matches what you would expect for the scent (e.g. yellow-coloured lavender scented soap would probably be a bit confusing, but yellow-coloured lemon soap or grey lavender soap would make more sense). I prefer French clay and it produces interesting muted colour effects in transparent melt and pour soap base (you end up with a beautiful translucent glow).

3. Is your soap getting too hot?

For melt and pour, it’s easy to overheat the soap while you’re trying to get it to melt, particularly if you use a microwave (which is another good reason to make melt and pour soap without a microwave). For better results, don’t add the fragrance until the soap has cooled to about 37 or 38 degrees celsius. For cold process, pack your soap with ice packs to keep it cool. If you absolutely need your soap to go through gel phase (where it gets very hot), you might have to just accept that your soap won’t smell very strongly if you use essential oils.

4. Consider using a blend of essential oils instead of one individual oil in a soap recipe.

If you have a base note, a middle note and a top note, the fragrance is more likely to permeate the soap in a more nose-catching manner. An example would be lavender as the base note, chamomile as the middle note and lemon as the top note. There are other ways to blend essential oils (you can blend them by effect, e.g. for sleep you might use lavender, chamomile and valerian, or you can blend them by group, e.g. you might want an overall citrus scent incorporating lemon, ten-fold orange and citronella. Different scents have different volatility (evaporation point, which is when fragrance is unleashed from your soap), so a blend of oils will mean your soap has a nice scent regardless of the air temperature, pressure or humidity.

5. Consider using melt and pour instead of cold process, and avoid hot process entirely if you want your essential oils to smell more strongly in your homemade soap.

There is more going on during soapmaking than the soap getting hot. The process of oils turning into surfactants (cleansers) is called saponification, and this is a chemical reaction. The heat is just a byproduct.

6. Wrap your soaps in something as soon as they are able to be unmoulded.

The wrapping needs to be something that doesn’t let oxygen in. I’ve gone through twenty alternatives to plastic for wrapping soaps in this article.

7. Burn incense when you make soap.

Sounds crazy, right? But from a chemistry point of view it makes sense. Scent escapes because it goes from an area of high concentration to one of low concentration. If the air in your soapmaking place is already saturated with a smoky scent, such as an incense stick (not the scent of an oil diffuser) you can prevent scent loss in the same way smoked salmon’s flavour is sealed into the fish (only, you don’t want your soap to smell of smoke which is why you don’t want to go too far with this method). This is a balancing act because you must always follow ventilation safety when working with chemicals.

8. Let your soap harden (and cure) near a dehumidifier or a big bowl of rock salt.

An electric dehumidifier or a big bowl of rock salt will pull the moisture out of the air, which means the scent will have nothing to evaporate into, so it will remain in the soap for longer.

9. Add a sea salt such as Himalayan pink sea salt to your soap.

Himalayan pink sea salt looks beautiful in cosmetics, and especially when it’s embedded in bars of homemade soap. The pink crystals sparkle in bright lights giving your soap an ethereal quality.

Himalayan sea salt will work as a nice exfoliant as well as helping stop the scent escaping. Just don’t put big chunky pieces of salt into a facial soap or you will get redness.

10. Mix in some charcoal, or do a charcoal swirl.

The benefits of charcoal in soap include being fantastic for acne and great at purifying in warmer climates, as well as being a good additive to prevent your fragrance disappearing before you ever get to use your soap! However, charcoal is a black powder and it will change the colour of your soap. Doing a swirl with charcoal is another option, so part of the soap is more fragrant, which will improve the overall effect while still letting you use nice colours in the rest of the soap.

That’s my 10 ways to fix your soap if your essential oil fragrance is too faint or if your essential oil fragrance doesn’t last. Do you have any other ways? Share them in the comments!