Help Understanding 'Flash Points'

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Nienna

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Hi,
So I understand the legal definition. But what I am wondering is more about how to use when making balms. So I struggle to get my balms down low enough to add essentials oils without them starting to harden and then I have to heat them up again anyway so its just a vicious cycle and to make the liquid enough to pour mean heating them up a temp that most essential oils don't like. I am mainly using Manuka oil for the healing properties, not the fragrance. I have looked online and cannot get a straight answer, does adding the essential oils when the mix is too hot burn off the properties of the oil or just the fragrance?
 
Wow, very interesting question. I am a soaper, so I know that when making cold process soap, the lye can get up to temps of 200+ I buy expensive essential & fragrance oils that can tolerate flash point (very hot temps), but I add my base oils (coconut, palm, olive) to the lye when they are within 10 degrees of each other & when the lye & base oils get no lower than 119 I add essential oils to retain the properties. The temp is just where I like it, because we gel (cp soap thang) The reason I do all that is not so much that I'll lose anything from (base oils) my coconut oils palm oil, more so that when I use the expensive essential oils/fragrance they can tolerate the heat, retain the smell and healing properties. Hope that helps. I know nothing about balms.
 
Flash point doesn't tell you anything meaningful about how fast a fragrance evaporates. Add fragrance to soap when the soap is as cool as is reasonable for what you're doing. A temperature around 120-130 F / 50-55 C works well for my hot process soap and lotions.

The flash point temperature is useful to know what might happen if a given fragrance is exposed to flame, as in a warehouse fire or shipping accident. It is reported by manufacturers for that reason. People have wrongly started to use the FP temperature to predict evaporation rates, but this idea is truly not valid.

If you look at the vapor pressures of fragrances versus their flash point temperatures, you will learn there are only tiny differences in vapor pressure for fragrances that vary hugely in their flash point temps. And you will also learn it doesn't make a lot of sense to use the FP temp to predict the vapor pressure -- in geek speak, the correlation between the two properties is very weak.
 
Flash point doesn't tell you anything meaningful about how fast a fragrance evaporates. Add fragrance to soap when the soap is as cool as is reasonable for what you're doing. A temperature around 120-130 F / 50-55 C works well for my hot process soap and lotions.

The flash point temperature is useful to know what might happen if a given fragrance is exposed to flame, as in a warehouse fire or shipping accident. It is reported by manufacturers for that reason. People have wrongly started to use the FP temperature to predict evaporation rates, but this idea is truly not valid.

If you look at the vapor pressures of fragrances versus their flash point temperatures, you will learn there are only tiny differences in vapor pressure for fragrances that vary hugely in their flash point temps. And you will also learn it doesn't make a lot of sense to use the FP temp to predict the vapor pressure -- in geek speak, the correlation between the two properties is very weak.

Thanks, but I am not making soap, I am trying to make a balm and I am not concerned about the fragrance so much as the actual beneficial properties of the essential oils. Whilst fragrance is nice I am using the essential oils because of their useful properties to add value to the balm not just scent.
 
@Nienna DeeAnna's point is that the flash point of a particular EO has nothing to do with, and cannot help to answer, your question about what temps will work for retaining beneficial properties of essential oils.

Flash point tells you the temp at which the EO will combust when exposed to an open flame. Thus, unless you are working over a gas stove or open fire, that flash point number is irrelevant to your balm-making. Your issue is to figure out the temps at which certain components evaporate (as opposed to combust), because those components are what provide the benefits you are seeking (as well as fragrance, which I understand is not your focus).

I hope that helps to clarify, and I hope you can find more information about the proper temperatures for retaining the desired beneficial properties of your EOs. You may want to check out Tisserand.com and see what resources they might have to offer about this issue. They may at least be able to tell you which components of certain EOs evaporate at certain temps. Good luck, and please let us know if you find out anything interesting about this.
 
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You are wanting to know how what temperature you can add your EO to your salve. You're going to have to talk to your supplier.
 
Thanks, but I am not making soap, I am trying to make a balm and I am not concerned about the fragrance so much as the actual beneficial properties of the essential oils. Whilst fragrance is nice I am using the essential oils because of their useful properties to add value to the balm not just scent.

My advice applies to lotions, balms, etc. as well as soap. I should have updated the wording to broadly cover all these products.

No one can definitively answer your question about changes to the "beneficial properties" of the essential oils due to temperature. None of us can offer anything more than personal stories and anecdotes. While stories and testimonials are nice to know, they aren't particularly helpful.

A person would need a well funded chemical research lab to attempt to definitively answer your question. In addition, every essential oil is made of quite different chemical compounds, so the data for one particular EO won't apply to a different EO ... or even to EOs from different varieties of the same plant species (lavendin vs lavender, for example).

As I said earlier, your best bet in the absence of definitive answers is to add the EOs to the product when it's as cool as possible yet warm enough for you to be able to finish the work you need to do -- filling containers, etc. Or look at using EOs in alternative products that don't require heating.
 

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