How much fragrance is 5%?

[seannasmommy]

I am using a fragrance from NG that recommends using no more than 5%. I don't know if that is 5% of my oils or 5% of the total soap that is produced. And how would I figure that?

 

[lsg]

I usually use .5 oz to 1 oz per pound of soap.

 

[cmzaha]

5% equals about .8 oz per lb of oil. I still usually go with 6% in soap or 1 oz per pound of oil

 

[godschild]

I don't mean to derail, but I have so many fos to keep up with their individual percentages. I just put .5 or 1 in the fragrance spot on soapcalc. .5 for the stronger scents and 1 for the weaker ones. Is that ok or do I absolutely have to do it by their individual percentages? Please forgive me for asking on your thread.

 

[DeeAnna]

The common wisdom is to calculate the fragrance as a percentage of the oil weight, but I have to say that I gently disagree with that.

If one makes lotion or lip balm, you'd figure the fragrance based on total weight of ALL ingredients in the recipe, so it doesn't make sense to figure fragrance for soap based only on the oil weight. Also my personal experience was showing me that my fragrance was generally too light when I used the "weight as % of oils" method.

That said, there is an issue about soap to keep in mind. Some moisture is lost from the soap during processing and curing, so it's not necessarily better to figure the fragrance as a percentage of all ingredients in the soap batch. I have found my typical soaps lose about 10% of their original bar weight after about 4-6 weeks of cure, so I figure my fragrance on the estimated weight of the soap after cure.

Example: My soap recipe calls for ingredients that weigh a total of 1000 g (oil+water+lye+additives)

My soap will lose about 10% of that weight during cure: 0.1 x 1000 = 100 g water loss
Ending soap weight = 1000 g - 100 g = 900 g final soap weight

I want my fragrance to be 5% of my soap after it is cured: 0.05 x 900 = 45 g

If you're into algebra:

Fragrance weight = (% fragrance / 100) x (0.90) x (total batch weight)

Fragrance weight = 5/100 x 0.9 x 1000 g = 45 g

This method is working pretty well for me, but as always YMMV (your mileage may vary).

 

[HoneyLady]

Okay, DeeAnna!

I was really interested in your response, and was following carefully
along . . . and you said the Dreaded A Word! {insert dramatic three note musical crescendo here}

After the anxiety attack (normal after the DAW), I read it again, then a third time. I think you are really onto something here, but . . .

Exactly how have you figured out your (average?) water loss over (how long?) time? That sounds like DAW.! roblem:

(Two soap makers leave on trains, one from Chicago heading west, and one from Des Moines heading east, at 8:00 pm. If the train heading to Des Moines is traveling at an average of 60 mph, and the train heading to Chicago is traveling at an average of 58 mph, which train will stop first for a herd of cattle on the tracks? What is the average weight per head of cattle? How many pounds of soap can be made assuming 100 lb. of tallow per head, with a soap recipe of 40% tallow, 20% coconut oil, 10% palm oil, 5% castor oil, and the rest as filler oil of choice, with 6% superfat, and unlimited FOs? What are the names of the soapers?) :lolno:

Is there a way to use your method with SoapCalc so I won't (I mean, probably will be less likely to) screw it up? Or you can include your formula? Can you come hold my hand? Dyscalculia, and all that. Numbers. Functions. Let me get my paper bag. :-(

Thanks!
~HoneyLady~

 

[seannasmommy]

I don't mean to derail, but I have so many fos to keep up with their individual percentages. I just put .5 or 1 in the fragrance spot on soapcalc. .5 for the stronger scents and 1 for the weaker ones. Is that ok or do I absolutely have to do it by their individual percentages? Please forgive me for asking on your thread.

No problem, godschild I don't know how to answer your question either, but I'm glad there are so many experienced soapers on here willing to help us.

 

[seannasmommy]

The common wisdom is to calculate the fragrance as a percentage of the oil weight, but I have to say that I gently disagree with that.

If one makes lotion or lip balm, you'd figure the fragrance based on total weight of ALL ingredients in the recipe, so it doesn't make sense to figure fragrance for soap based only on the oil weight. Also my personal experience was showing me that my fragrance was generally too light when I used the "weight as % of oils" method.

That said, there is an issue about soap to keep in mind. Some moisture is lost from the soap during processing and curing, so it's not necessarily better to figure the fragrance as a percentage of all ingredients in the soap batch. I have found my typical soaps lose about 10% of their original bar weight after about 4-6 weeks of cure, so I figure my fragrance on the estimated weight of the soap after cure.

Example: My soap recipe calls for ingredients that weigh a total of 1000 g (oil+water+lye+additives)

My soap will lose about 10% of that weight during cure: 0.1 x 1000 = 100 g water loss
Ending soap weight = 1000 g - 100 g = 900 g final soap weight

I want my fragrance to be 5% of my soap after it is cured: 0.05 x 900 = 45 g

If you're into algebra:

Fragrance weight = (% fragrance / 100) x (0.90) x (total batch weight)

Fragrance weight = 5/100 x 0.9 x 1000 g = 45 g

This method is working pretty well for me, but as always YMMV (your mileage may vary).

Thank you so much, DeeAnna!

 

[DeeAnna]

I came close to snorting coffee out my nose, Honey Lady! Since it's my first cuppa joe of the day, I managed to swallow every drop of that precious caffeine loaded mouthful, but it was a struggle.

Love your "algebra problem" -- you spent a lot of time on that 'un! I dread that kind of story problem too, and I'm pretty good at math. It's problems like those that have made so many people algebra-phobic.

"...Exactly how have you figured out your (average?) water loss over (how long?) time?..."

I took a freshly cut bar and weighed it every few days for about 2 weeks. Weighed it every week or so for another few weeks. Made a chart of weight loss versus time (see first pic). When the weight loss was pretty slow (soap never seems to stop losing weight), I called it quits and looked at the total amount of loss. Did this with a couple of different bars with totally different recipes, and got about the same results -- very roughly about 10 percent water loss during cure.

This experiment ignored any water loss in the soap pot and in the mold. Although I know there is some weight loss during those steps, I didn't look at that. Next time!

The amount of weight loss depends on the amount of water in the recipe and how you make the soap. If you use "full water" (about 28% lye solution concentration), your soap will have somewhat more water loss than soap made with a more concentrated lye solution. CPOP soap or soap that goes through gel is likely to start out drier than no-gel soap put in the fridge or freezer. A soap made in a slab (tray) mold is likely to lose more water than soap made in a loaf mold.

To give you a basis for my results, I usually use 33% lye concentration, allow my soap to gel, and use a loaf mold.

"...Is there a way to use your method with SoapCalc so I won't (I mean, probably will be less likely to) screw it up?..."

SoapCalc can't directly give you the "fragrance as % of total recipe weight" answer. It does give you the "Fragrance" weight based on the oil weight, the "Oils" weight, and the "Soap weight before CP cure or HP cook" when you view the completed recipe (see second pic).

Here's how you could adjust the fragrance weight to be based on total soap weight. Assume that your soap will lose 10% of its weight during cure -- in other words, a bar will weigh 90% of its original weight after cure. Then:

Fragrance based on total soap weight = (Soapcalc fragrance wt) x 0.90 x (Soapcalc soap weight before CP cure or HP cook) / (Soapcalc oils weight)

Example:
Fragrance wt = 50 g x 0.90 x 1448 / 1000 = 65 g

Hope this helps!

 

[DeeAnna]

"....5 for the stronger scents and 1 for the weaker ones. Is that ok or do I absolutely have to do it by their individual percentages?..."

I don't use SoapCalc, so I can't answer as an experienced user. I'm also a relative newbie at using FOs, although I've used EOs for a number of years.

When I calculate the FO amount to use in any product (soap, lotion, lip balm, etc.), I keep track of the seller's and IRFA recommended dosages for my FOs in a computer spreadsheet. I keep track of the resulting scent intensity and quality in my soaping notebook when I use that fragrance. I also record my EO scent blends in my soaping notebook.

If I want to increase or lower the FO or EO dose in the future or adjust the ingredients in an EO blend, I can use the info in my notebook and spreadsheet for making those decisions.

Whether you want to track your fragrance dosages more closely or keep using your current method is your decision. There are no "scent police" to enforce "the rules". It's up to you!

 

[HoneyLady]

:wave:

Thank you, DeeAnna !!! Sorry for making you snort your coffee, tho.

I truly appreciate you taking the time to 'splain this to me, Lucy. I was always told to read word problems through all the way, and try to figure out what they were asking. Alas, it always seemed as if the info they provided (distance, rate time) had nothing to do with the question! (Pounds of tallow, FOs and soap recipes!) Of course, now I'm older and realize as average people go through life, all the math problems we encounter are word problems! I know this and this . . . how do I figure out this ??

I am glad to hear that your method of calculation was as simple and obvious as , "I cut a bar and weighed it regularly." I can DO that!

It seems that the 90% was a common standard for YOU. In your opinion, will the amount of shrinkage change based on location and ambient humidity? A soaper in Phoenix will get different results than a soaper in Houston? Or would it be more likely that the AMOUNT will be similar, but the RATE of CHANGE faster or slower? Just wondering before I go cut a bar . . . I understand why a slab of soap would evaporate water at a faster rate than a loaf -- surface area exposed, depth of soap, etc. I *recognize* important facts when you hit me over the head with them, I'm just never sure whether to divide or multiply ! ;-)

I have been keeping notes on how scents morph and last over time in my soaps, so this is a great addition!

Thank you for holding my hand !

For some light and entertaining reading, I highly recommend the kids' picture book called Math Curse. I have a copy, and I loaned it to my kid's math teacher, who liked it so much she bought her own copy!

~HoneyLady~

 

[DeeAnna]

"...It seems that the 90% was a common standard for YOU...."

Yes, this is the number that I personally am seeing. What I've gleaned from other soapers, however, is that my results are not too far off from what others see. I'd say a 10% to 15% weight loss for a "normal" type of soap during a 4-6 week cure would be typical.

"... In your opinion, will the amount of shrinkage change based on location and ambient humidity?..."

Air humidity and temperature will affect weight loss, certainly. I think this will be especially true when the bars are freshly cut. In a humid climate, air flow and dehumidification can be really helpful during the initial 4-6 week cure period.

This initial loss in weight can be really dramatic. As an example, the two "superlye" soaps (Recipe 1 and Recipe 2 in the chart) were made with far more water than a typical CP soaps. These bars had a huge loss in weight in the weeks after they were first cut. The weight loss for these "non-normal" soaps (the two longer curves) illustrate just how much water can evaporate from a bar of soap right at first. The two shorter curves are the weight loss for the two "normal" soaps I talked about in my earlier post. All four soaps, after enough time passes, eventually lose weight at about the same rate.

I'm not so sure air temperature and humidity have that much effect after the usual 4-6 week cure. I think the rate of migration of water from the center of the bar to the surface of the soap is what controls the rate of weight loss after the initial cure. I shrink wrap my bars in non-perforated plastic after their cure, but the bars are still slowwwllly shrinking and losing weight even in a plastic wrapper.

Honestly, there is no one right black-and-white answer to this. I have just tried to make a sensible estimate of weight loss and am basing my fragrance decisions on that. If my thinking proves to be incorrect, then I'll revise and move on. :wink:

"...kids' picture book called Math Curse..."

I'll check into that!