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lady-of-4

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So, I'd been sitting here doing some extensive searching into using Rosin in LS. If it's ok, i'd like to share the little bit that I've found, and input would be most welcome for future use to others.

Rosin (colophony, Greek pitch) is a solid form of resin obtained from conifer types plants, ie pines, produced by heating liquid resin to remove the liquid terpene components (turpentine). It is not pine tar. The 2 are not the same, in that pine tar is made from pine wood, via high temps and destructive distillation. Both are used in soap making, however, according to Summer Bee Meadow, it's not recommended for liquid soap making; why, I'm unsure of, though I know there are commercial liquid soap products on the market. So again, I don't know.

Rosin is comprised primarily of resin acids, most notably Abietic and Pimaric, acids not normally seen when using soap making calculators/formulators, as we use fatty acids. There are different color variations of Rosin, from very pale yellows to almost blacks, all transluscent, and the coloring indicates quality of the resin. Location source, ie Hondouran, Brazilian, Chinese, etc, also determine quality, supposedly. Rosin, when used in soaps, adds a special emollience, clarity, as well as bubbles, which we all love about a good soap. In Catherine Failor's book, Making Natural Liquid Soaps, she notes that rosin also emparts it's own preservation properties to soap. The accurracy of this, I'm unsure of. That can be something to look into later.

All this information is great, and most of it readily available about rosin, as an industrial item. But there isn't much mention about HOW to use it in soap, particularly in liquid soap making, as Catherine Failor discussed in her book. She includes recipes, but not how to handle the material, ie how to prepare it, when to add it, etc. Today, I was able to finally stumble upon 1 blog from a man who had the material left over from his job. The blog, Tooling Up, gives a little bit of a step by step to his process. It's not uber detailed, procedure wise, but pictures are with comments as to what is going on in them. He also references Failor, and one of her reciepes, during his method. It is quite simple and to the point, and basically, instead of melting the rosin right along with his fats, he melts it seperately in another pot, then adds it during trace, as the rosin causes the mixture to seize up prematurely. Unfortuantely, he doesn't mention temps, so we're on our own to figure out what is best for us and our heating devices. After adding it to the rest of his mixture, his soap turned a deep golden color. Almost a like a heavy or medium bodied raw honey color. Especially after dilution. And from the looks of his pictures, beautifully clear. He also shared his spreadsheet that he made up, based off of a Failor reciepe, that includes SAP values and amounts used. It really is a very basic recipe, with coconut and olive oils, and rosin.

So, I guess, now for the good stuff. Here's the link to the blog so you all can see for yourself:
http://tooling-up.blogspot.com/2013/02/making-liquid-rosin-soap.html

His spreadsheet:
https://docs.google.com/file/d/0B-JHo9tm7cE7UHExalJMZ2oyQmc/edit

And just for some unforseen reason, the internet hates us all and should these links stop working in the future, basic info about the recipe:

coconut oil 300g (65.2%)
olive oil 90g (19.6%)
rosin 70g (15.2%) SAP: 182 KOH Needed: 12.74g NaOH: 9.09g

I'd like to also add a few other values of Rosin that I was able to find on my own, though I don't have links to my exact sources at this time. Took me some time looking this stuff up. So I'm honestly not inclined to try again right now. I have the SM3 program, so Rosin is added in as an oil and having these properties to input was nice.

Specific Gravity: 1.06. The program will tell you this seems a bit too high. I dunno. I put it in anyways. It's what I was able to dig up.

Iodine: 125. I believe because of the iodine input, the program was able to give me a hardness quality of 1.6 and moisturizing quality of 1.4. I cannot say if this is accurate or not. It's what I'm looking at right now. I could be wrong about the correlation.
What i've also found, is that the SAP value can vary depending on the coloring of the Rosin used, but from what I've found, the average is around 180. I nthis recipe, it's 182, and other sources will say 160-170 or 170- 190. Again, it depends on the Rosin you get. I believe somewhere here in this forum, another gentleman posted a chart with different SAP values.

I'd also opened a thread on Summer Bee Meadow's forum page about rosin, since they have it included in their list of oils and their properties, but they don't have it included in the oils selection for the calculator. If I get any more info, I'll add it here later. And yes, their site is back up. I'm totally stoked!! Here's hoping it stays that way.

Again, if there is anything else anyone would like to input, of course it's more than welcome, a this post is intended for those wanting info about Rosin. And the more added, the better.
 
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Great info - thank you! Interesting reading and I've wanted to use rosin in a soap for awhile. I wonder if you can collect your own rosin or if there is a specific type of tree you have to harvest it from. I'm thinking it would be way cool to harvest some cedar rosin since I live in forest area... I see some experiments in my future...
 
Im quite sure you can collect your own. But you'd still have to find a way to process out the turpentine.

I'm glad you found this info useful. I hope others will as well.
 
I would like to know where to purchase, the only stuff I found was for dancers and too expensive to add to soap. I checked my soap suppliers and none of them had it listed. Any ideas?
 
I would like to know where to purchase, the only stuff I found was for dancers and too expensive to add to soap. I checked my soap suppliers and none of them had it listed. Any ideas?

Hi! I purchased mine, cheapest, on Ebay, for $11.49, that's including the $5 shipping. I got a pound of it for now. But you'll have to type colophony in the search, otherwise, you'll get results for the violin stuff. There are a few other sites that sell it, but I'm unsure of the names at this time.
 
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Its not about liquid soap, but sure. I bookmarked some interesting stuff so lets see if I can find it, its on my kindle.

This is the book, its free http://www.amazon.com/dp/B004UJKZSY/?tag=skimlinks_replacement-20

It very much focuses on soap making on the commercial side, but I like the chemistry detail it goes into and have found a lot of interesting info. I'm not very far into it yet though. Here's some stuff that may be interesting:

"The better grades are light in color and known as water white (w. w.) and window glass (w. g.). These are obtained from a tree which has been tapped for the first year. As the same trees are tapped from year to year, the product becomes deeper and darker in color until it becomes almost black.


The constituents of rosin are chiefly (80-90%) abietic acid or its anhydride together with pinic and sylvic acids. Its specific gravity is 1.07-1.08, melting point about 152.5 C., and it is soluble in alcohol, ether, benzine, carbon disulfide, oils, alkalis and acetic acid. The main use of rosin, outside of the production of varnishes, is in the production of laundry soaps,although a slight percentage acts as a binder and fixative for perfumes in toilet soaps and adds to their detergent properties. Since it is mainly composed of acids, it readily unites with alkaline carbonates, though the saponification is not quite complete and the last portion must be completed through the use of caustic hydrates, unless an excess of 10% carbonate over the theoretical amount is used. A lye of 20° B. is best adapted to the saponification of rosin when caustic hydrates are employed for this purpose, since weak lyes cause frothing.


While it is sometimes considered that rosin is an adulterant for soap, this is hardly justifiable, as it adds to the cleansing properties of soap. ... To saponify a ton of rosin there are required 200 lbs. soda ash,
1,600 lbs. water and 100 lbs. salt. [boiling soap method]"
 
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Haha, that's actually who I got mine from. Didn't get the powdered though. Wanted to see what the small crystals looked like.
 
I'm going to go out on a limb and say no because I'd think they add something to it to make them rock hard, compared to the raw stuff that a bit crumbly.
 
Thanks Lady

Anytime. Like I said, if you all find any more info, please add it. When I made this post, I made it a point to use the tag feature so it could be easily found by anyone wanting info on Rosin.

And if anyone does use it, please share your experience.
 
I found some from a seller in GA. You can buy powdered pine rosin on ebay. http://www.ebay.com/itm/1-lb-Powder...373?pt=LH_DefaultDomain_0&hash=item416799c2d5

Thanks for the tip, lsg! I found this seller's website this evening. The prices are the same on the website as on eBay. I plan to buy direct and save them the eBay fees. http://www.diamondgforestproducts.com/~shop/main.html

It looks like the cost comes down a HUGE amount if one buys in bulk, but I'm not quite sure what I'd do with 100 pounds. :grin:

One of the things I notice about this company's rosin is that it is made from managed forests in Georgia, USA, and the rosin is very clean and a nice pale amber color. Maybe it's not the "water white" color mentioned by the old soapmaking books, but plenty nice enough for today, considering the turpentine/rosin industry is nearly extinct in the USA.

Another seller on eBay was selling rosin that looked dirty and very dark -- not the best ingredient for making a quality soap.
 
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