Percentage used

[Cherrydene soapy]

An IRFA guideline is only about human safety. It doesn't tell you anything about anything else. So you gotta use some common sense and look at the whole picture. For example, some FOs have an IRFA limit of 100% for Cat 9 (soap). Does it make sense to "make soap" with 100% FO? So there's a practical limit for how much scent you can stuff into a soap and not run into problems of the fragrance weeping out or the soap not functioning properly as soap or other problems.

My personal rule of thumb for soap is to use no more than 8% FO based on weight of oils, if the IRFA guideline allows that much. If I go much above 8%, the fragrance gradually weeps out of the soap with unattractive results. Others are comfortable with higher top end percentages (again assuming the IRFA guideline allows), so don't take my personal rule of thumb as gospel truth. As always, YMMV.

And as I said earlier, an IRFA guideline is the % in the whole finished product, not based only on the % of oils. If you use the IRFA guideline but based it only on % of oils, you'll be using a cautious amount of scent. It's far better to be cautious than to overdo.

Thank you so I now understand what your saying about how much to use of FO, when you say the weight of the ‘finished product’ do you mean oils and water/lye together?

 

[KiwiMoose]

Most of the FOs i use say that it can be used between 3 - 6%. So, in my 1kg batch of oils - I dump in the whole bottle ( 30ml) which tends to weight around 25g. If I like the scent, I might then go back and buy a bigger bottle. Mind you, I have an ever-increasing assortment of fragrances that need to be tried - they all sound so delicious!

 

[MGM]

At 0.8 % usage rate, this FO sounds as toxic as, well, lye!

 

[Cherrydene soapy]

I thought that was low why would it be toxic? X

 

[MGM]

I thought that was low why would it be toxic? X

Right, if it's recommended to only use a teeny bit of the FO, it must be toxic, one way or another. But if you're following their guidelines (which I still find surprising, that sounds like it ought to be for a leave-on product, not wash-off), then you should be safe.

 

[LilyJo]

Will send you the document in a sec - please bear in mind that whatever the IFRA recommended usage of a FO is, if you are selling it still needs to pass safety assessments and they often recommend a max of 2-3%.

I know that cinnamon blends can be as little as 0.5 - 1% (which is tiny) but we have generally stick to 3% or the max IFRA amount, whichever is lower.

 

[Zany_in_CO]

I'm a bit of a Lazy Daisy and math-challenged as well, so i have two tools I use to calculate the amount of EO/FO to add to whatever I'm making... Soap or other B&B products:

Majestic Mountain Sage Fragrance Calc
https://www.thesage.com/calcs/FragCalc.html
Although the list of EOs and FOs isn't comprehensive, I can usually select something similar and get good results.

Frann's Essential Oils Safety Quick Guide
http://www.frannsalthealth.com/blog/essential-oils-safety-quick-reference/
Once again, not comprehesive, but does cover most widely used EOs

 

[KiwiMoose]

I'm a bit of a Lazy Daisy and math-challenged as well, so i have two tools I use to calculate the amount of EO/FO to add to whatever I'm making... Soap or other B&B products:

Majestic Mountain Sage Fragrance Calc
https://www.thesage.com/calcs/FragCalc.html
Although the list of EOs and FOs isn't comprehensive, I can usually select something similar and get good results.

Frann's Essential Oils Safety Quick Guide
http://www.frannsalthealth.com/blog/essential-oils-safety-quick-reference/
Once again, not comprehesive, but does cover most widely used EOs

Thanks for these Zany - I was wondering about essential oil usage so that's very helpful.

 

[Zany_in_CO]

You're most welcome, Kiwi.

 

[maxine289]

I always calculate the FO percentage based on the total batch weight which means that if the Category 9 recommended limit is 4%, for a batch with 48 oz of oils with a total batch weight of 95 oz, I’d use 3.8 oz of FO. If I was basing the FO percentage on the weight of oils only, I’d use only 1.92 oz. 3.8 oz is 7.9% of the oil weight which is more than double the percentage of the calculation based on batch weight. I’ve always struggled with which is the correct way to calculate this.

 

[cmzaha]

Sorry to be complete nit wit but I can’t see it, I can see the safety and something else but no IFRA details sorry to be a pain x

It looks like you need to download the technical data for the fragrance and the IFRA will be one of the downloaded files. This is located under the fragrance picture

 

[DeeAnna]

I always calculate the FO percentage based on the total batch weight....

Bear in mind the total batch weight is not the finished product weight, meaning the weight of product the customer receives. The fragrance should be within skin safe limits when the customer receives it. If you calculate on total batch weight and use the maximum dosage that IRFA allows, the scent in the soap as sold (or given away) may exceed the safety limit.

I estimate there is at least a 10% loss due to curing, so you need to build that into your calculations.

"...I’ve always struggled with which is the correct way to calculate this...."

You and most of the rest of us. I suspect this is the reason why so many ingredients used in soap are proportional to the oil weight, since that weight is a constant value throughout the life of any given batch of soap. The lye will vary depending on superfat, purity, average saponification value, etc. The water can vary depending on the soap maker's preferences. The additives can vary too.

 

[maxine289]

Bear in mind the total batch weight is not the finished product weight, meaning the weight of product the customer receives. The fragrance should be within skin safe limits when the customer receives it. If you calculate on total batch weight and use the maximum dosage that IRFA allows, the scent in the soap as sold (or given away) may exceed the safety limit.

I estimate there is at least a 10% loss due to curing, so you need to build that into your calculations.

"...I’ve always struggled with which is the correct way to calculate this...."

You and most of the rest of us. I suspect this is the reason why so many ingredients used in soap are proportional to the oil weight, since that weight is a constant value throughout the life of any given batch of soap. The lye will vary depending on superfat, purity, average saponification value, etc. The water can vary depending on the soap maker's preferences. The additives can vary too.

Hadn’t thought about curing or that the other ingredients might vary from batch to batch. Good thought. I think I’ll start using FO as % of oil weight. More consistent and will reduce batch costs, which is always a good thing.