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Make your own soap 2 - adding fragrance

Written by Elinor and Jacqui on March 15th, 2012.      0 comments

Jumping into the shower and lathering up a bar of exquisitely scented soap is a simple but delightful pleasure.
dorothyWhen I was small, my childless godmother gave me a beautifully packaged soap: Dorothy Gray Midnight. It was my first experience of perfume, and it sat in my bedside cupboard for more than a decade, available to evoke glamour and mystery at one sniff. When I turned 21 I unwrapped it, and it provided numerous beautifully scented showers and baths. I don’t know how Dorothy Gray managed to get such a lovely fragrance to endure – she is a hard act to follow!
So… what are the options for fragrance in soap?co rosehip 1
Essential oils are pure and natural, but need to be used with care and discretion.
Fragrance oils have the disadvantage of being manufactured rather than extracted simply from plants. Care is also needed with them.
It’s likely that my childhood soap was perfumed with a mix of synthetic and natural fragrances, with fixatives added to slow the evaporation of the perfumes.

For our kits, we have chosen some of our favourite fragrances, ones that are well behaved and distinctive: lavender, rose geranium and litsea cubeba essential oils, and rose fragrance oil.

Lavender is an all-time favourite perfume and rose geranium is a delightful floral perfume that is even popular with men. We also use rose fragrance oil as the cost of rose essential oil is prohibitive.
Litsea cubeba colours the soap yellow and gives a lovely lemon smell, less harsh than lemongrass, and it lasts much better than citrus essential oils, which tend to fade quickly.

mintOther oils to think about are palmarosa, with a fragrance which Chelsea describes as 'fruity, light and playful', and oils from the mint family, fragrances that you either love or loathe. Peppermint and spearmint are favourites around here. We find them invigorating, and appreciate their 'tenacity' - they don't fade away quickly.
With melt and pour soup, it is relatively simple to make it smell divine because there is rarely any reaction between the soap and the fragrance.
But with cold-process soap, it can be a tricky business. More on that later.
How much?
Essential oils and fragrance oils are a similar strength, and are added at a rate of around 20ml per kilo of soap. 
That’slittledropper 1:50, or 2%.
If you are using a very expensive oil, you may want to add only 1%. If you want the fragrance to come through clearly, or if the oil is delicate rather than strong, you can add 3%.
Adding fragrance to melt and pour soap
 Add after colouring, just before pouring into moulds. Gently but thoroughly stir in the measured amount of fragrance. Essential oils vary in intensity, even the same oil from one batch to another. If you find that you want a stronger perfume, you can add a wee bit more and stir again. And if the soap starts to set, warm gently before pouring!
Adding fragrance to cold-process soap
 The thing that makes cold-process soapmaking so fascinating and addictive is that it has a life of its own – it’s a series of chemical reactions that humans have made use of for five thousand years, a process of transformation that seems so unlikely that it’s got the magic of alchemy.
Because these reactions are happening from the moment you combine the lye and the oils, the soap is more open to influence than melt and pour, where you are adding fragrance to a stable, finished product.
Fragrance is usually added to cold-process soap at trace – when a spoonful of the mixture is poured on top of the rest and it doesn't sink in. Some fragrance oils and a few essential oils cause unwanted changes in the soap. The most frustrating thing that can happen: Your batch may seize, ie suddenly go hard when you add the oil - before you have a chance to pour it into moulds!
cinnamon bark
Spicy oils can be tricky.
They often affect colour. Essential oils such as cinnamon and clove will turn your soap brown. You may be perfectly happy with this, as the colour is appropriate!

Spicy fragrances sometimes affect the setting process, and may cause your batch to seize.
So when you use spicy oils or fragrance oils, add them at the first sign of trace, or before, and mix them in by hand, quickly and thoroughly.
The fragrance may have other effects on your batch.
It can develop texture problems: become grainy, oily or otherwise unpleasant.
Most annoying is when saponification isn’t perfect throughout the batch. You are probably using a stick blender or something similar, but this doesn’t actually move everything off the sides of the pot. It’s a really good idea to hand stir as trace approaches, using a spatula to scrape the sides of the pot.
Even then, you may have problems. Sometimes the soap looks fine – nicely homogenous – but it sets with veins or crystals of sodium hydroxide, which makes it a disaster area. It’s the soap around the side of the pot that is especially vulnerable. Make sure you have scraped the side a few times during the mixing process so that soap is incorporated into the body of the pot.
While you are building up experience, it’s a good idea to leave the scrapings behind when you fill your moulds. There is nothing more disheartening than discovering that the last bits you scraped into the middle of your mould have developed veins of sodium hydroxide, ruining the whole lot!
There will be lots of chemical reactions taking place in the 24 hours after you fill your mould, and essential oils can influence some of these.
 Your soap may:notebook
  • Change colour during the curing process
  • Quickly lose fragrance
  • Heat up more than usual
As a soapmaker, always take notes. Write down all the details about the batch you are making. Your notes will be invaluable when the unexpected happens, and will enable you to become well acquainted with your ingredients and equipment. Best of all, they will mean that you won’t make the same mistake twice!
Every batch of essential oil is slightly different, so there are no hard-and-fast rules. Some serious soapmakers test oils before committing themselves to using them in a big batch. They gather all the fragrance and essential oils they are considering using, and prepare a small labelled container for each one – then make some soap and pour into the small containers, stirring in the named oil. This way you get to see which oils cause sudden and extreme reactions.

wrapStoring soap to preserve fragrance
You can help retain the fragrance in your soap by storing it wrapped or at least covered. Left exposed to the air, most fragrances evaporate. And it seems to be the expensive oils that evaporate most quickly!

Making gorgeous-smelling soap is a fascinating undertaking. Observe carefully, write down everything, and soon you will develop routines for making perfect soap that looks and smells just the way you want it.