How to Dilute Perfume Materials

Ah, perfume making! It’s so romantic, so poetic…so FULL OF MATH.

Why dilute?
Perfumers often need to dilute their materials to 20%, 10%, or sometimes even 1% or .5% or more before adding them to a blend. This serves a number of purposes – from wasting less material while blending to making it easier to work with trace amounts of strong-smelling materials.

What material to use as a diluting agent?
Typically, you’ll want to dilute in perfumer’s alcohol. You should dilute in whatever medium you would be working in – so if you are making oil-based perfumes, dilute in oil. Some people prefer to dilute in Dipropylene Glycol (DPG), which is a common odorless solvent that is completely soluble in water, alcohol, and some oils – and it also is a humectant (attracts water) and has fixative properties. A strictly all-natural perfumer will not want to use DPG since it is a synthetic, but if you’re concerned about safety, don’t be. According to the Environmental Working Group, DPG is safe / very low risk.

Use Weight/Weight Dilutions
An important consideration is that when professionals are talking about dilutions in the perfume industry, they are talking about diluting by weight rather than by volume. So assume all dilutions on any materials you purchase or for any formulas are listed in weight/weight.

Creating a Dilution from Materials at 100% Concentration
Creating a dilution from 100% pure raw material is relatively straightforward.  In the chart below are the ratios in generic “parts” – this would work for drops, ml, grams, etc. as long as you keep the units of measure consistent – but as I mentioned, most professional perfumers work by weight (grams) – so let’s assume this is grams.

If you don’t want to do the math, here is a weight/weight dilution calculator.

You can also check out this nice tutorial on dilutions and blending from Chris of Pell Wall Perfumes. He gives a very thorough step-by-step approach.

Aroma Material Dilutant Total Parts Percent Dilution
1 1 2 50%
1 2 3 33%
1 3 4 25%
1 4 5 20%
1 9 10 10%
1 19 20 5%
1 99 100 1%
1 199 200 ½%

Creating a Dilution from Materials at Different Concentrations
What if you want to do something a little more complicated? For example, I have a bottle of Benzoin Absolute pre-diluted to 50%.  I have a perfume formula that calls for Benzoin at 20% dilution.  How do I dilute a 50% solution to 20%? (These are the questions that make former English majors clutch their heads in agony and wish they’d paid a little more attention in Chemistry lab.)

Well, it turns out there’s a relatively straightforward formula for this: C1V1=C2V2.  C=Concentration and V=Volume. Now, I don’t want to do this by volume – I want to do it by weight. If I wanted to be super accurate, I should probably take into account molecular weight. But since the amounts I’m dealing with are relatively low and I don’t need to be that insanely accurate, I’m not going to worry about molecular weight. (Also, if a chemistry person is reading this and wants to explain how to do this absolutely properly, I’m all ears! Please comment!)

Okay! So let’s figure this out. How do we dilute a 50% solution to a 20% solution? I’m about to do some math. If, like me, math makes your head hurt – you can skip the pain and go use this handy-dandy dilution calculator.

But hey, if you want to see how the math works, here goes. I already know my concentrations. All I have to decide is what final weight I’d like to end up with. For kicks, let’s decide on 5 grams final weight.  So!  Here’s how it would work out:

C1W1=C2W2

    • C1 = 50% = .5
    • W1 (the weight of the 50% solution to add) = unknown
    • C2 = 20% = .2
    • W2 = 5 grams

.5(W1)=.2*5g
.5(W1)=1g
W1=2g

So, okay – now I know that I need 2 grams of my starting 50% solution, and I want to end up with a final weight of 5 grams. So 5 grams – 2 grams = 3 grams. Which means I need to add 3 grams of my diluting agent (alcohol) to 2 grams of the 50% material to get 5 grams of 20% material. Or…

Starting % Ending % How many grams First solution? How many grams diluting agent to add? How many grams final solution?
50% 20% 2g 3g 5g

That’s it! Do you have a better method for calculating dilutions? If so, please comment! I’d love to hear from you.

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Amber Spice Perfume Recipes: Oil-Based vs. Alcohol-Based

So, this is Experiment No. 2 in blending along with Mandy Aftel’s book, Fragrant. Earlier I created her solid Amber Spice perfume, and now I’m exploring those same notes in oil-based and alcohol-based versions.

Amber Spice Perfume: Oil-Based Version

Here’s what you need for the oil-based perfume:

Amber Spice Oil-Based Perfume Supplies

Supplies for creating the oil-based version of Amber Spice perfume.

Raw Materials*

  • Fractionated coconut oil
  • Labdanum absolute
  • Cinnamon bark essential oil
  • Rose absolute
  • Lime essential oil

*Out of courtesy to the author, I’m leaving off the amounts of each raw material. You can find them in her book.

Equipment

  • 25 ml graduated beaker or cylinder
  • Stirring rod
  • Glass eyedroppers (1 per essence)
  • Bamboo ear cleaner (for scooping out drop-size amounts of semi-solid materials)
  • 1/2 oz bottle (dark glass – blue or amber); you can also use a roller ball bottle
  • Tiny funnel

Steps

  1. Measure out the fractionated coconut oil into the graduated beaker.
  2. Add the essences (using a separate eye dropper for each one), and stir after adding each one to mix well.
  3. Use the tiny funnel to transfer the blend to the bottle.
  4. Seal tightly, label with the name and date, and let it age for at least a couple of weeks to let the scents marry.

How did it work? How does it smell?

It was incredibly easy to make the oil-based perfume. After aging only about a week (I haven’t been able to wait long!) it smells about the same as the solid version of the same perfume – an initial impression of “cola” (lime + cinnamon) followed quickly by leathery labdanum. This isn’t very surprising since the oil-based perfume uses the same essences in the same proportions as the solid. The fractionated coconut oil absorbs into the skin relatively quickly and smoothly. Still, I find the projection for both these sorts of perfumes to be relatively weak, and for some reason applying the oil-based perfume – while fine – is less enjoyable than applying the solid perfume. So, if I want to make a skin scent in the future, I’ll probably stick to a solid perfume format. Still, you can’t beat this recipe for ease!

Amber Spice Perfume: Alcohol-Based Version

Here’s what you need for the alcohol-based perfume:

Amber Spice Alcohol Perfume Supplies

Supplies for making alcohol-based Amber Spice perfume.

Raw Materials*

  • Perfumer’s alcohol
  • Benzoin absolute
  • Vanilla absolute
  • Labdanum absolute
  • Cinnamon bark essential oil
  • Rose absolute
  • Jasmine absolute
  • Fresh ginger essential oil
  • Lime essential oil
  • Bois de rose essential oil

*Out of courtesy to the author, I’m leaving off the amounts of each raw material. You can find them in her book.

Equipment

  • 15 ml graduated beaker or cylinder
  • Stirring rod
  • Glass eyedroppers (1 per essence)
  • Spray bottle

Steps

  1. Add each of the essences into the spray bottle, using a separate eye dropper for each one. Start with the bases (benzoin, vanilla, labdanum), then add the heart notes (rose, cinnamon, jasmine), and then the top notes (ginger, lime, bois de rose). Smell after each addition to experience how the blend is progressing.
  2. Measure out the perfumer’s alcohol into the graduated beaker, then pour it into the spray bottle with the essences.
  3. Shake well to combine.
  4. Seal tightly, label with the name and date, and let it age for 4-6 weeks to let the scents marry.

How did it work? How does it smell?

This recipe was *a lot* harder to pull off than the solid perfume and the oil based perfume because it uses two really challenging natural materials: Benzoin and Vanilla. These materials are solid to semi-solid, and very hard to work with undiluted. Fortunately, I had the good sense to purchase Benzoin absolute that had been diluted to 50% in alcohol, so I was able to add it in drops. Still, this left me puzzled as to how many drops to add. Should I double the drops since it was a 50% dilution? I assumed so, and did. But what about the vanilla? It had the consistency of tar – thick, gooey, and totally impossible to get at with an eye dropper. I tired warming it gently by placing it in a bowl of hot rice (you should never microwave essential oils). This made it slightly more liquid – and I was just barely able to use the eye dropper to add it to the blend. Still, I don’t think I added an accurate amount of vanilla – it got everywhere! In the future, I think I’ll either need to buy prediluted Vanilla absolute or dilute it myself by 50% (by weight) before working with it. Which means….I need to purchase a scale.

As for how it smells…well, it only has aged for 1 week, and quite honestly it smells like cream soda. I may have OD’d the benzoin and the vanilla. Sigh. I need to try the recipe again with less of those base notes. Still, it smells delicious (if you want to smell like a cola float!) and reminds me of those Bonne Bell lip smackers from the 70s when I was a little girl. The scent is also much more complex and layered than the oil or solid perfume with better intensity and longevity too – so I think I’m hooked on using alcohol as a carrier medium for future blends.

UPDATE: On Handling Viscous/Semi-Solid Materials in Mandy Aftel’s Recipes

Confused about the dilutions, I reached out to Mandy to ask her how to handle the viscous/semi-solid vanilla, benzoin, and fir absolutes she uses in her recipes. She was kind enough to get back to me, and explained that she doesn’t dilute them. Instead, she uses them at 100% strength, and uses a tiny bamboo ear cleaner to scoop out the material and add it to the blend.

Supplies for Creating Perfume

Perfume Organ

Perfume Organ, Fragonard Perfume Museum, Paris by Nico Paix

Beginner’s Kits

Raw Materials – Naturals

  • Aftelier* – Quirky selection of unusual perfumers botanicals. Fast shipping. No minimum.
  • Aqua Oleum – Excellent UK source for essential oils from Julia Lawless.
  • Aromatics International – Expensive oils connected with the Aromahead Institute. Site has excellent information.
  • Eden Botanicals* – EOs, CO2s, Absolutes. Excellent quality, wide selection, no minimum purchase.
  • Enfleurage – Aromatics from the natural world. Specialize in Frankincense. Also offer hydrosols and more.
  • Liberty Natural Products* – Amazing selection. Includes isolates and more. $50 minimum.
  • Mountain Rose Herbs – Wide selection. Somewhat expensive shipping. (Mentioned more often by home aromatherapists than perfumers. Never tried.)
  • Nature’s Gift – Just tried them for the first time for more aromatherapy-type oils. Also have wide selection of hydrosols, carrier oils, waxes and butters. Well researched and reasonable prices.
  • White Lotus Aromatics* – Gorgeous, superior quality naturals personally sourced from around the world. $100 minimum.

*Companies with an astrix * are the ones I order from most frequently. Eden Botanicals is my “go to” supplier.
Also helpful: Providence Perfume offers a useful review of some of the best/worst essential oils she’s ever purchased.

Raw Materials – Synthetics

Beeswax

Carrier Oils
Carrier oils are for making oil-based perfumes, solid perfumes, or other body products. Do not add them to alcohol-based perfumes (they will separate and make a mess). Some carrier oils will go rancid fairly quickly. Fractionated coconut oil and Jojoba oil are two of the longest-lasting.

Alcohol
For alcohol-based perfume, use perfumer’s alcohol a.k.a specially denatured (SD) alcohol, which is 95% ethanol that has been denatured with an additive. The denaturing is done for regulatory reasons to prevent consumption. When purchasing perfumer’s alcohol in the United States, use 40b, which is denatured with t-butyl alcohol & Bitrex. Do not use 39c, because it contains diethyl phthalate (DEP), a.k.a. phthalates for which there are serious health concerns. For natural perfumers, there are also organic alcohols that have been denatured with natural materials. If you are not planning to sell your perfume, you can also use Everclear / Pure Grain Alcohol instead of Perfumer’s Alcohol. It should be 190 proof (95% alcohol) ethanol. In the USA, PGA is available for purchase in some states but not all. Some natural perfumers will also use Vodka for perfume, but it’s not as desirable as Everclear/PGA due to the lower alcohol content. For cleaning, you can use Isopropyl alcohol, Vodka, or PGA.

Dipropylene Glycol (DPG)
DPG is an odorless, colorless synthetic carrier oil that is perfect for diluting fragrances to 10% or 1% to be used for sniff tests / educating your nose. It is oil-based, but water and alcohol soluble.

Bottles and Packaging

190 Proof!

190 Proof!Every journey has to begin somewhere, and it may take to you funny places. Today I found myself, a suburban mother of two, in Tony’s Liquors asking for a bottle of Everclear.

I immediately blushed, explained that it was for perfume, and then told a long rambling story about how I hadn’t thought about PGA since the ’90s when we used it for Hunch Punch. Then I was embarrassed I’d said THAT, babbled some more, blushed more, and ran out while the cashier and owner chuckled.

Outside, a panhandler hit me up for $1 (still discombobulated, I gave him everything in my back pocket) and asked what I was drinking. “I’m not drinking it, it’s for perfume!” I waggled my bottle at him and smiled as I hopped in the car, worried he’d ask for some. But instead he asked, “Cool, is that what you do?”  I paused. “Yes. I mean, it’s just a hobby.”  He smiled.

I guess this is what I do? Cheers y’all. So begin the adventures.