Hot process question

[PuddinAndPeanuts]

I tried hot process for a batch or two and added the EO's while the soap was too hot. The fragrance burned out of one. So, two questions:
- how cool can I let hot process batter get to add the fragrance without having it firm up too much?
- my fragrance was added at 5%, but it's a blend of 3 EO's. As long as I keep the total % of each EO (between the first and second time I'm fragrancing the batch) below the safety maximums, there's no reason I can't add another 5% of that blend is there? (Bergamot, cedar & lavender- sounds terrible, smells flippin' amazing).

 

[lsg]

IMO, the % of essential oils added should be the total, not 5% of each. I usually find out what the flash point of the FO or EO is and add after the soap has cooled a little below that.

 

[HowieRoll]

The handful of times I've HP'd soap I have let it cool down to about 150F-ish before adding the EOs. It seems that is about as cool as I can get it so that it's still stirable and not developing hard bits of soap as I mold it.

I also typically scent my HP soap at 3% oil weight with essential oils. That is to say, 3% total EOs, not 3% of each one (and assuming all EOs in the blend are being used at safe levels, i.e. if the blend was 50% cinnamon and 50% clove I would certainly not use them at 3%). I'm not certain I'm understanding your question correctly, but if you are asking if adding 5% and then an additional 5% of an EO blend is okay (totaling 10%), I would think that would exceed safe usage guidelines.

 

[SunRiseArts]

It will depend. Each fragrance or EO would have a different flash point. You always have to add it after that temperature.

Some FOs gave as high flash points as 200, some as low as under 140. Check were you bought it for the information.

 

[WeaversPort]

Flashpoint vs Vaporizing

IMO, the % of essential oils added should be the total, not 5% of each. I usually find out what the flash point of the FO or EO is and add after the soap has cooled a little below that.

It will depend. Each fragrance or EO would have a different flash point. You always have to add it after that temperature.

Some FOs gave as high flash points as 200, some as low as under 140. Check were you bought it for the information.

While you don't want to burn the essential oils, you can add them at a temperature higher than their Flashpoint. My understanding of Flashpoint, is that is when a substance gives off vapors that could be ignited. That is what determines whether or not an oil ships ground vs air.

They don't, however, disappear into vapor.
http://www.soapmakingforum.com/showpost.php?p=594940&postcount=9

 

[Obsidian]

What I've found helps it's to transport the finished HP into a warm stainless bowl then add the scent.
The few times I've left the soap in the crock, it was the hot crock that burned off the FO.

 

[WeaversPort]

What I've found helps it's to transport the finished HP into a warm stainless bowl then add the scent.
The few times I've left the soap in the crock, it was the hot crock that burned off the FO.

I like that idea. I've not done HP except for once and it didn't have fragrance. I'll keep that in mind for the future though!

 

[SunRiseArts]

While you don't want to burn the essential oils, you can add them at a temperature higher than their Flashpoint. My understanding of Flashpoint, is that is when a substance gives off vapors that could be ignited. That is what determines whether or not an oil ships ground vs air.

They don't, however, disappear into vapor.

My comment was not because the FO would burn, but I made a lot of HP batches, and just like in CP, FO does affect the batter in my personal experience. Also, the lower the temperature you pour your FO, the more the fragrance will stick in the long time. Or at least, that is what has happened to me.

I could be wrong, as I know is not a scientific fact, although several candle websites, including NG mention the fact that pouring higher than the flashpoint. They say, although is for candle making, that "The right temperature is extremely important to ensure that the fragrance oil binds properly with the soy wax. You also do not want to risk “burnoff”. Burnoff is the adding of a fragrance oil at too hot of a wax temperature. Because a flashpoint on a fragrance oil is the highest temperature the fragrance can handle before breaking down, burnoff can affect the scent in the finished candle. " I imagine something similar could happen with soap.

Soap Queen says " We haven’t noticed substantial scent fading at higher temperatures, but it is something to take into consideration. If you’re using a low flash point scent, you may want to avoid gelling the soap. During gel phase, soap can get as hot as 180 ° F. Read more about gel phase here. It may be something to consider when making hot process soap as well, as the soap temperatures are typically around 160 ° F or hotter."



PuddinandPeanuts, I turn off my crockpot, and take the ceramic bowl out o the pot, and let it cool until 130 more or less. Then I add my fragrance, and transfer to mold. That way I do not have to use another container.

I am sure there are many ways of doing all of this, everyone needs to find what works for them.

 

[WeaversPort]

My comment was not because the FO would burn, but I made a lot of HP batches, and just like in CP, FO does affect the batter in my personal experience. Also, the lower the temperature you pour your FO, the more the fragrance will stick in the long time. Or at least, that is what has happened to me.

PuddinandPeanuts, I turn off my crockpot, and take the ceramic bowl out o the pot, and let it cool until 130 more or less. Then I add my fragrance, and transfer to mold. That way I do not have to use another container.

I am sure there are many ways of doing all of this, everyone needs to find what works for them.

I'll freely admit I don't have a lot of experience with hot process, so I'm happy to bow to anyone who has worked through the process.

My main purpose for sharing was, that if a Flashpoint is below or close to the point where soap was starting to resolidafy, you can still add it to the soap. The higher temperature difference won't cause it to break down completely.

Avoiding overexposing fragrance oils to heat, however, makes a lot of sense either way.

 

[NsMar42111]

I do the same as sunrise except I don't know the exact temperature I let them cool to-I do it until I start to see the top go chalky looking and then I know it's now or never...took a lot of batches to be able to recognize the look though. I go as low as I can for EO's and any strong FO's after almost fumigating myself with eucalyptus once .... regular FO's I don't bother to cool, I just add them when the soap is done cooking