Benzoin Resin... The Other Scent Fixative

RESINS ROCK!

After covering both Opoponax and Copal resins in previous blog posts, it probably comes as no surprise that I positively adore botanical resins! I love grinding them down to make infusions, scented oils and soap batches with them; I love burning them as incense and reveling in their rich, dimensional aromas; I love the olfactory experience of different resins mixed with other aromatic notes in an expertly blended perfume, or the way they look and feel when tumbled around in the palm of my hand. That’s exactly why when a specific soap project came my way this week, I knew precisely what I wanted to do with it! Enter: Benzoin resin! Some of you reading this may already be familiar with Benzoin resin in soap making (specifically Benzoin powder), but for those who are unfamiliar with it, I wanted to take a moment and introduce you to this wonderfully unique resin, as well as share what makes it awesome for soap making! 

THE FASCINATING WORLD OF BENZOIN RESIN!

Benzoin in a balsamic gum resin which comes from several species of trees in the Styrax genus. It’s hugely popular in the perfume-making industry, due to its sweet, vanilla-like aroma, as well as its ability to act as an effective scent fixative. The most common type of Benzoin resin used for incense, soap making and perfumery is Benzoin Siam, which is obtained from the Styrax tonkinensis, and is plentifully found throughout Thailand, Laos, Cambodia and Vietnam.

Benzoin Siam resin is widely popular within the perfume industry due to its scent fixative properties, since it’s known to slow the evaporation and air dispersion of both fragrance and essential oils. Likewise, many soap makers rave about Benzoin’s scent anchoring abilities in handmade soap, but this is not without some common complaints too. Many soap makers dislike the gritty texture Benzoin resin can often impart in soap, as well as its tendency to turn soaps tan when used in higher amounts. The common belief is that this discoloration is due to the color of the Benzoin resin powder itself, but this is only a very small part of it. You see, when Benzoin resin powder becomes saturated with oil or liquid, it turns a dark amber-brown color, which can certainly have an effect on the color of one’s batch oils. However, it’s actually something we all know, and are very familiar with, which is the real culprit here! Incorporated at higher usage rates, Benzoin resin can potentially turn soaps tan because it naturally contains vanillin... That must be why it smells so delicious!

REMEDIES & BENEFITS

Many soap makers feel the benefits outweigh Benzoin’s potential to discolor to tan, and/or impart a gritty texture to their soaps because of its effective scent fixative properties, but there are ways to remedy this! For any potential discoloration Benzoin resin may cause, a lower usage rate can be employed, and/or skin-safe colorants, such as micas and oxides, can be used to “mask” any mild discoloration. Even its gritty texture can be remedied so that anyone can enjoy the benefits Benzoin resin has to offer, with none of the unwanted trade-offs!

It can take quite a while before fully dissolving, but Benzoin resin is water soluble (hot water works best for this purpose), and it will even dissolve (very slowly) in oil with prolonged exposure to heat. Although there are those soap makers who prefer to dissolve their Benzoin resin powder prior to incorporating it into their soap batches, most commonly, Benzoin resin powder is added to a recipe’s batch oils at trace. Even dissolving the Benzoin resin beforehand can still result in bits and pieces of undissolved resin being present within the finished bars of soap.

To ensure my own Benzoin resin wouldn’t impart a gritty feel or texture in this soap project, I decided to create an infusion with it instead. Once ground into a very fine powder (or purchased in powder form), the typical usage rate for Benzoin resin in cold process soap is generally 1/2tsp to 1tsp per pound of batch oils. As a scent fixative, Benzoin resin can be used alone, or in conjunction with other popular scent fixatives, such as natural clays. Along with its lovely aroma and effectiveness as a scent fixative for fragrances and essential oils, Benzoin resin also contains natural sugars, minerals and enzymes, and is prized for its antibacterial, anti-inflammatory, antioxidant, antifungal and antiseptic properties.

As for its antioxidant properties, soap makers who wish to prevent oxidation and oil rancidity in their handmade soaps, but prefer to use natural alternatives, as opposed to chemical preservatives and/or chelators, can enjoy Benzoin resin for this purpose as well. Benzoin resin is a valued antioxidant, and is widely used as a natural preservative, extending the shelf life of handmade soaps. Adding Benzoin resin to oil-based recipes and preparations helps to delay oxidation and spoilage; the two main culprits of “DOS”, or “Dreaded Orange Spots”. 

Now that we know many awesome things about one of my personal favorite resins, Benzoin, let’s make a resin infusion! In this week’s blog, I’ll show you how to make your very own Benzoin resin infusion from scratch, as well as share my favorite way to add it to cold process soap, without worry of discoloration or a gritty texture. Of course, we’ve got some stunning micas and a heavenly fragrance oil to gush about too, so let’s get this soapy show on the road!

MAKING A BENZOIN RESIN INFUSION

In its pure form, Benzoin resin looks like your standard driveway gravel... It even kind of smells like it too! But wait a minute! Didn’t I just get done telling you how yummy it smells? I did, and it does, I promise! Now, for me at least, the aroma of Benzoin resin has never been strong enough to impart a detectable aromatic presence in cold process soap, but working with it is divine! It’s the heat from the infusion process itself that really brings out the richness of its fragrant character, but to get there, we need to grind it first. Of course, you can always skip this step if you’d prefer... Benzoin resin is available in different mediums, which include powders and tinctures, to name a few, so if you’d rather purchase it already fine-ground, that’s A-Okay too!

Luckily, Benzoin is a soft resin, and grinds easily with minimal effort, so if you’ve got a mortar and pestle handy, in no time at all, you’ll have your very own Benzoin powder! Take some extra time to really get that Benzoin resin ground down to as fine a grain-size as possible, then measure out the amount you’d like to add to your soap recipe. For example, a recipe consisting of 32oz of batch oils (2lbs.), and a desired usage rate of 1/2tsp Benzoin powder per pound of oils, would require a total of 1tsp Benzoin Powder.

As discussed, the standard usage rate for Benzoin powder in cold process soap is around 1/2tsp to 1tsp per pound of oils, but feel free to adjust this to your liking... You can certainly add less, or more as desired. For me, 1stp/PPO has served me well in the past, so that’s the usage rate that I prefer. Once ground into as fine of a powder as possible, transfer your measured Benzoin powder to a heat-proof container or jar, then pour a carrier oil directly on top of it. Any light carrier oil will do; such as refined olive oil, rice bran oil, grapeseed oil, canola oil, sweet almond oil, sunflower seed oil, etc.

I prefer not to add my Benzoin resin to my soap recipe at trace. Rather, I prefer to add it as one of my recipe’s base oils, which I’ve infused the Benzoin resin into. In this particular recipe, I chose rice bran oil. Since it doesn’t take much Benzoin resin to enjoy its benefits in your handmade soaps, I formulated rice bran oil into a beginner-friendly cold process soap recipe at 3% of the recipe’s total batch oil weight. This 3% rice bran oil total (or whichever carrier oil you like best) will make up my full oil/resin infusion, and when complete, I’ll combine it with my remaining batch oils in the same way I’d incorporate any other base oil into a recipe.

Give your oil/resin mixture a good stir, then secure the top with a lid, or some other way to effectively keep condensation out of your container or jar. To a crockpot, add enough water to create a water bath for your infusion (About 2 to 3 inches of water from the bottom of your crockpot should do the trick!), then place your oil/resin mixture directly into this water bath. With crockpot lid on and the heat set to “Low”, allow your infusion to do its “thing” for no less than 4 hours. About 4 to 6 hours of infusion time is ideal.

Once your oil/resin mixture has maintained steady heat for at least 4 hours, go ahead and carefully remove the infusion from its water bath (Use oven mitts to prevent accidental burns!), and allow it to cool down a bit. Once cooled to a more skin-safe temperature, strain the infusion well with a fine-mesh tea strainer or cloth coffee filter. To ensure you’ve strained the infusion really well, you may need to do this 2 or 3 times, but it’s worth it for that smooth, creamy bar of soap you’ll end up with!  In my own experience with making this infusion, the majority of the Benzoin resin had dissolved by the end of a 5-hour infusion, imparting a lovely shade of golden amber to the rice bran oil. However, when I strained the infusion, it still had a small amount of sticky, black, tar-like residue, which had settled to the bottom of the jar. This is why thoroughly straining the infusion is important, since you don’t want any of that sticky goo getting into your soap. Once you’ve finished straining the infusion well, the next step is to go ahead and take a big, sweet whiff of Benzion resin at its best! Many people liken the aroma of Benzoin resin to vanilla, but to my nose, there’s so much more than just vanilla going on in its scent! If sweet honey, creamy vanilla and cozy, toasted, marshmallows had a beautiful, aromatic,” love-child" together, Benzoin resin would be IT! As soon as your Benzoin resin infusion has been thoroughly strained and allowed to cool, it’s ready to be added to your remaining batch oils and made into a fabulous batch of soap!

BENZOIN GOIN’ IN SOAP!

The design of this soap is completely random, since I thought this would be a great opportunity to show you how to incorporate a Benzoin resin infusion into cold process soap while working on a specific project I needed to complete at the same time (Killing two birds with one stone here... Metaphorically speaking, of course!). While the actual design of this soap may seem completely irrelevant, the colors used in this soapy project turned out to be quite relevant! I imagine many soap makers feel hesitant to give Benzoin resin a try in their own soap recipes for the same reason I initially was... I was worried it would turn my soaps tan or brown and distort all my mica colors in the process. I decided to make this batch of soap a gradient of one color, going from dark to super light, to show you just how free you are to use any shade of any color that you’d like! From the dark to the light, the classically gorgeous shade of “Purple Vibrance” mica, alone and blended with “Winter White” mica, remained beautiful and unaffected by any darkening!

But what about the batch oils themselves? Would incorporating our amber-colored Benzoin resin-infused rice bran oil in with our other batch oils affect the color of the soap batter? The answer: Not so much! Thankfully, these batch oils are pretty light anyway (The recipe is down below for anyone interested in trying it!), so they weren’t really affected. Maybe just a touch more yellow-ish than usual, but absolutely nothing that “Purple Vibrance” mica couldn’t handle!

The actual design of this soap was so simple and so fun, and you’re more than welcome re-create this soapy design in your own soap projects, or simply use it as inspiration to allow your imagination to run wild! If you happened to have read my previous blog where I made a batch of soap with a Copal resin-infusion, you might remember that the Copal resin really sped things up in my soap. Thankfully, that’s not an issue at all with Benzoin resin! I used it alongside a healthy amount of kaolin clay and a 33% lye concentration, and had no problems with acceleration at all! I was able to happily execute an “ombre-inspired”, tilted-layer design (With gorgeous “Cheshire Cat” mica lines between each layer!), and take my sweet time while doing it!

I did realize after the fact that I might have had a little bit of an “unfair advantage’ with the fragrance oil I used for this project though! Benzoin resin is valued, among many other things, for its scent fixative properties, but this is a fragrance oil that simply needs no fixin’! Easily one of my most favorite fragrance oils EVER, Nurture Soap’s “Seven Isles” fragrance oil is my aromatic version of ocean-salty, crisp, clean, heaven on earth! Crazy-accurate to the scent it duplicates, “Seven Isles” fragrance oil smells like fresh, rain-washed fruits; clean, captivating neroli, and sun-warmed caresses of salty sea air, carried on an affectionate ocean breeze! I will never grow tired of making soap with this fragrance oil, and I love it even more for the fact that its potency and scent retention are out of this world! No exaggeration, I have a bar of soap I’ve saved that was made with this fragrance oil so long ago, I can’t even remember when I made it anymore! Despite my fading memory, the one thing that hasn’t faded is this fragrance oil in my soap! It’s as true, fresh and strong as the day I made it... Whenever that might have been! *Edited to add: Looking up my review on the Nurture Soap’s product page, I made that batch of soap in February, 2019. One year and seven months later, and that last bar is still going strong! 

While I won’t be able gauge just how well our Benzoin resin infusion helped to enhance and/or add longevity to this specific soap batch, since it already contains one of the most enhancing and persevering fragrances I've ever made soap with, I did have an awesome experience working with it in this project, as well as making an amazing-smelling infusion with it! By the time I finished this batch, and the soap was ready to be “tucked in” for the night, my whole kitchen and living room areas were filled with the sensational scent of “Seven Isles” fragrance oil! Perhaps the Benzoin resin was working some of its magic already!

THERE’S ALWAYS A RESIN FOR SOAP MAKING!

Whether you’ve made soap with Benzoin resin before; were familiar with it, but still hesitant to try it; or had never heard of it previously, but your interest was piqued, I hope this blog was a helpful tool for you, even if in the smallest of ways! Maybe you’ve used Benzoin resin before, but wanted to find an easier way, or a way to bypass the gritty texture and/or tan discoloration. Maybe you’ve always been interested in trying it, but avoided doing so for those exact reasons. Perhaps this was new territory for you, but you’d love to explore it some more. Maybe you’ve used it countless times before, and know of even better ways to utilize it in cold process soap (And if that’s you, please do share in the comments section below! I’d love to hear your favorite methods, tips and/or recommendations!). The soap making life is a fascinating one indeed, in that the learning process and new opportunities for growth never really end... They just evolve and change to match where you’re at in your specific soap making journey!

Incorporating resins in your cold process soap recipes is as broad and as vast as your imagination!  There are so many incredible options to choose from, with each variety offering something different and unique in application! If soap making with resins intrigues you, GO FOR IT! Grab some sample sizes of various botanical resins you think you might enjoy, then let that vibrant imagination of yours run wild! There’s always a resin for soap making, and always a reason for soap making too... After all, “Because I just feel like it, that’s why!”, will always be a perfectly acceptable answer! 

SOAP RECIPE:

  • Lye @ 5% Superfat
  • Distilled Water @ 33% Lye Concentration (2:1/Water: Lye)
  • 37% Olive Oil
  • 28% RSPO Palm Oil
  • 25% Coconut Oil
  • 7% Castor Oil
  • 3% Rice Bran Oil, Infused with Benzoin Resin (*Or Other Carrier Oil of Choice. 1tsp/PPO Finely-Ground Benzoin Resin - Infused Per Directions Above)
  • 6% “Seven Isles” Fragrance Oil
  • 3% Sodium Lactate (*Optional)
  • 1/2TBS - 1TBS PPO White Kaolin Clay (*Optional. Added Directly to Fragrance Oil & Blended Well.)
  • 1tsp/PPO Nurture Soap’s Mica(s) and/or Soap-Safe Colorant(s) of Choice (*Optional)

SOAP FROSTING:

  • Lye @ 5% Superfat
  • Distilled Water @ 33% Lye Concentration (2:1/Water: Lye)
  • 35% Olive Oil
  • 28% RSPO Palm Shortening (AKA: No-Stir Palm)
  • 27% Coconut Oil
  • 10% Castor Oil
  • Nurture Soap’s Low Sweat, Clear Soap Base – For Embeds (*Optional)
  • 1tsp/PPO Nurture Soap’s Mica(s) and/or Soap-Safe Colorant(s) of Choice (*Optional)
  • Nurture Soap’s Enviroglitter (For Decoration. *Optional)