Adding oils to lye water or lye water to oils

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Primrose

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In all the soap making tutorial videos I have watched, the lye water is tipped into a bowl of melted oils before stick blending.

Is there any reason not to do it the other way around, ie. tip the melted oils into the lye water container and stick blend it there?
 
I have the opposite in terms of containers, the lye container is deeper and taller thus better for stick blending, which is why I wondered if there's any harm in tipping the oil into the lye water (or lye milk in my case)
 
There is science to it and I want to say it's similar to the reason we always add the NaOH to water and not the reverse: the lye tries to react with everything. It's easier and safer if you can control how much lye is trying to react with everything than the reverse.

(I don't know the exact science. I just remember a similar explanation at some point.)
 
I have the opposite in terms of containers, the lye container is deeper and taller thus better for stick blending, which is why I wondered if there's any harm in tipping the oil into the lye water (or lye milk in my case)

Why not just switch which container you use for which? Mix your lye in the smaller container and your oils in the larger one?
 
Actually it has to do with splash potential. You are more likely to splash whatever is being poured into than what is being poured. You do not want lye water splashing out onto you and your surroundings.

You say you can be careful? You only have to be wrong once for major problems to happen. Be safe, people.

Susie makes a great point about "splash potential." As a rule I don't pour oils into lye, but I do have that 1 recipe. . . .

Just keep in mind how often we hear about injured people who "should have known better." Complacency doesn't help matters, either. I could share three "soapy" occurrences when I "should have known better," but they don't paint me in the best of light!
 
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I wouldn't add oils to the lye either, primarily for the splash potential, but also for cleaning the lye pitcher as well. I have a dedicated lye pitcher, and just rinse it well with cool water and wipe it out when I'm washing my soaping stuff. Plastic especially is difficult to get squeaky clean, and I'd be afraid of a trace of oils remaining in my lye solution container when I used it the next time. Maybe not a valid point, I really don't know.
 
I wouldn't add oils to the lye either, primarily for the splash potential, but also for cleaning the lye pitcher as well. I have a dedicated lye pitcher, and just rinse it well with cool water and wipe it out when I'm washing my soaping stuff. Plastic especially is difficult to get squeaky clean, and I'd be afraid of a trace of oils remaining in my lye solution container when I used it the next time. Maybe not a valid point, I really don't know.

I agree with this. I used to put my soapy stick blender into my lye pitcher when I was done. But I noticed that I was much more likely to have problems with the lye not dissolving completely after I did that, even though I washed the pitcher. So now my lye pitcher holds nothing but lye water (or lye coffee sometimes). It gets rinsed with hot water after each batch, and occasionally run through the dishwasher.
 
I agree with the viewpoints people have been sharing. There are some good, practical reasons to pour the lye solution into the fats. But from purely a "will it explode" point of view ... it doesn't matter whether you pour the lye solution into the fats or pour the fats into the lye solution, as long as you take reasonable care to not splash. Fats react slowly with lye, so either way is pretty safe.

If you are using a high % of fatty acids or rosin, however, it can be very important whether you pour the lye into the FAs/rosin or vice versa and also how fast you combine them. These ingredients react very fast with lye and release a lot of heat. If you just dump these ingredients together without thinking about what you're doing, the resulting fast heat release can trigger a volcano.

***

Just a safety tip for those who are new to soap making -- When making the lye solution, it is absolutely important to always pour the alkali (NaOH or KOH) into the water, rather than vice versa -- never pour water into the alkali.
 
Thanks for the feedback, I found a different container to use.for my lye so will now be able to do lye into oils :)
 
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