HP Questions - small batch OPHP

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I’m finally starting to play around with oven process hot process. I’ve refreshed myself on the research I did back in 2019 and 2020 and made a test soap that isn’t a failure 🤣. Now I have a couple of questions.

1. I’m planning to start with relatively small batches. Is a 2.2 L container large enough for a total batch size of 650 g? What about a total batch of 775 g? This is the container I’m thinking about using. It’s 6.5“/16.5 cm tall.

2B9D6D04-7471-4D9F-B708-FAA339ABCB3A.jpeg

I‘ve convinced myself that a cylindrical container is a good idea because less of the soap batter will be exposed to air. Will it increase the potential for a volcano or some other problem I’m not anticipating? My next larger container is a standard cooking pot. The volume and dimensions made it really difficult to SB without adding air bubbles. I’m trying to avoid buying yet another container.

2. Is yogurt essential for producing a fluid soap? I’m planning to start at 28% lye concentration. What options do I have if I don’t want to add yogurt or other dairy and want to reduce the potential for warped soap? If I start adding clays or other dry ingredients I will rethink the lye percentage.

TIA
 
I've not tried OPHP, but I have done high-temp countertop HP, and high-temp stovetop HP. For best fluidity, I needed:
  • all additives and utensils to be warmed.
  • lye concentration between 25-30%
  • post-cook add-ins of FO/EO + sodium lactate + hot sugar water (which is great for dispersing colorants, too) + either yogurt, coconut milk, or goat milk.

Not sure about the shape or size of the container, but hopefully someone else can chime in there.

Good luck - I'm looking forward to your experiments!
 
A narrow container gives less space for the batter to rise up before spilling over than a wider one, especially if it builds up on itself (imagine pouring fizzy drinks in a narrow glass or a wider glass - the fizz has less space to spread out so it spreads up!) but narrow has the advantage of allowing better stick blending.

Why is air exposure a bad thing here? More surface area would also allow better heat transfer to more batter
 
Thanks @AliOop for that very concise summary and options!

Something I read online last night said to never fill a crockpot more than half full for HP. Since I’m making the soap in the oven, I won’t be standing there watching it every minute. At the batch sizes I’m planning, the batter will fill about a third or less of the volume of the container, which seems like it should be okay. I’m mostly wondering if anyone has a rule of thumb that works for oven hp. Maybe I should just assume it will be trial and error based on method particulars and my oven.

Thanks @The Efficacious Gentleman for keeping me thinking. When I watch people make hp on YT, they‘re often talking about the issues with soap drying out on the sides of the container and on the top of the soap. The lower and slower, no stir crockpot hp method reduces the need for stirring, which leads to less water loss, but the large amount of surface area in a relatively shallow crockpot increases the chances of getting dried out soap along the edges. Making hp soap in a container that reduces surface area relative to volume should reduce water loss from the bulk of the batch and, if I’m careful about how I stir at the end, the percentage of soap that will make its way to the walls of the container. I agree that heat transfer to the center of the batter would be slower, but does it matter? I’m not planning to be in a rush when I do this.

Here’s my first soap for critique. I added sodium lactate, then eos, then sour cream (don’t laugh, I forgot that I didn’t have yogurt), and then on a whim, decided to add a little warmed alkanet infusion, which accounts for the grey color. No purple (duh, alkanet needs to gel), but the color distribution helps to accentuate the consistency/texture of the soap when it was poured. It wasn’t fluid, but it was thin enough to flow a bit. It settled into the mold easily, with few air pockets. The soap is scented with lavender and it smells fabulous.

78669D86-35B9-4F61-9503-61B3DF176147.jpeg
 
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Thanks @AliOop for that very concise summary and options!

Something I read online last night said to never fill a crockpot more than half full for HP. Since I’m making the soap in the oven, I won’t be standing there watching it every minute. At the batch sizes I’m planning, the batter will fill about a third or less of the volume of the container, which seems like it should be okay. I’m mostly wondering if anyone has a rule of thumb that works for oven hp. Maybe I should just assume it will be trial and error based on method particulars and my oven.

Thanks @The Efficacious Gentleman for keeping me thinking. When I watch people make hp on YT, they‘re often talking about the issues with soap drying out on the sides of the container and on the top of the soap. The lower and slower, no stir crockpot hp method reduces the need for stirring, which leads to less water loss, but the large amount of surface area in a relatively shallow crockpot increases the chances of getting dried out soap along the edges. Making hp soap in a container that reduces surface area relative to volume should reduce water loss from the bulk of the batch and, if I’m careful about how I stir at the end, the percentage of soap that will make its way to the walls of the container. I agree that heat transfer to the center of the batter would be slower, but does it matter? I’m not planning to be in a rush when I do this.

Here’s my first soap for critique. I added sodium lactate, then eos, then sour cream (don’t laugh, I forgot that I didn’t have yogurt), and then on a whim, decided to add a little warmed alkanet infusion, which accounts for the grey color. No purple (duh, alkanet needs to gel), but the color distribution helps to accentuate the consistency/texture of the soap when it was poured. It wasn’t fluid, but it was thin enough to flow a bit. It settled into the mold easily, with few air pockets. The soap is scented with lavender and it smells fabulous.

View attachment 64530
Hi, I don't actually know what oven HP is BUT about the standing around. I cover with a see through lid (can use plastic wrap), do not stir, do not open, do not pass go (just kidding, monopoly memories coming back) and when the batch has finished cooking then the entire soap will show gel. Takes about an hour and nothing rises, no bubbles, just science doing its work from the outside to inside, the soap changes color to gel. Absolutely no stiring and no ph testing needed because the gel phase has shown complete process visibly. Personally I was excited to find this method. Hope it helps you too.
 
@HoliHealerz Are you doing your HP in a crockpot? What temperature do you bring it up to?
Hi Mobjack, everyone,
I do not have a crock pot. I either do the make shift double burner with a pot on the top or a glass bowl. My lid sits on top but it does not precisely fit but it works. I keep the gas burner on medium and sometimes turn it lower for fear that the glass will crack but then turn it up to medium again. Either way eventually it reaches its threshold and the entire batch gels from bottom and outwards to the top center. Its VERY cool to watch science working this way. Actually I cannot find my thermometer so thats why I don't check temp.

@HoliHealerz Are you doing your HP in a crockpot? What temperature do you bring it up to?
This is yesterday's HP batch in this same method. The mixture was a very nice consistency and no yogurt needed adding, didn't dry too fast in molding. Placed it in the freezer to harden. Several hours later, demolded.
 

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This is yesterday's HP batch in this same method. The mixture was a very nice consistency and no yogurt needed adding, didn't dry too fast in molding. Placed it in the freezer to harden. Several hours later, demolded.
Thanks for posting the photo. The soap looks super smooth I’ve watched YT soap maker Tellervo make a double boiler/stovetop hp soap. It sounds like your method is similar. I’m delving into hp to see if it makes a difference for some of the EOs and natural colorants I use, not because I want soap in a hurry. Being able to see the soap is a definite advantage of a stovetop method, especially because I have little experience with hp.
 
Thanks for posting the photo. The soap looks super smooth I’ve watched YT soap maker Tellervo make a double boiler/stovetop hp soap. It sounds like your method is similar. I’m delving into hp to see if it makes a difference for some of the EOs and natural colorants I use, not because I want soap in a hurry. Being able to see the soap is a definite advantage of a stovetop method, especially because I have little experience with hp.
Thank you for your response. Yes it was very workable and 'plopable'😆 I tapped it after each few plops and it settled well. I will check on the Youtube video that I got it from. Her videos are so amazing and calm and sue even teaches about a gel from flaxseeds which I want to watch again because right now I use katira kond or silica gel and its wonderful on the skin and in the soap but adding another gel thats not aloe would be extra luxury. Personally I do not subscribe to the wash off product and not being useful for skin philosophy FROM EXPERIENCE. I am public on youtube videos and and have been TOLD before my creams that my skin has changed and looks glowy (whether its true or not is not the issue - they said it) and the only thing I had changed was my formula of soaps. Cleansing is half of the whole of health care and skin care too. It MATTERS what we use and it makes a difference even being wash off. Thats my stand until I witness otherwise. Long answer to a short post from you. I apologize.
 
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I made some progress yesterday, but still have plenty of room for improvement. From left to right, the first soap is from the batch above; the second is colored with the alkanet infused oil added before the cook; the third is colored with a tiny bit of 91% isopropyl alcohol colored by madder that I added before the cook for the light soap (the pigment clumped a bit, but did not seize the batter) and the alcohol was added after the cook for the darker soap. The base batter for the madder soap was on the fluid side, but the darker reddish soap less so. I used a hanger swirl in that one, and got closest to a real swirl near the bottom of the soap, but I also ended up with air pockets.

Issues are:
  • discoloration in the second soap - could this be due to incomplete blending of the lavendar eo? The uppermost layer of soap, which was at the bottom of the container, was mixed a little better compared with the soap that went in below it.
  • ”leafing“ in the second soap - temperature too low?, too much time between getting spoonfuls of soap in the mold? My techniques and rhythm are unpracticed and I think both could be true, but any other critiques/ideas are welcomed.
  • Based on the pink soap, I think I need to start the design process with the soap at a higher temperature and possibly up my water a little. I wasn’t able to measure the temp of the batter for the pink soap just before I started adding it to the mold, but the the temp was just below 170F when I added the eos as the final addition.
D4085FD4-E618-4E7D-A8D5-E9D221A8A840.jpeg


I’m excited about the way the eos smell in these soaps. They’re really present and bright at 3%. I used lavender again for the second one and grapefruit and bergamot for the soap on the right.

I used the ss cylindrical container posted above for the second batch. It was too tall for good mixing access. I switched to a 1L+ pyrex measuring cup in the water bath for the pink batch, but blended the oils and lye together to light trace in a #5 container before I poured the batter into the glass container. The radiant heat from the heated glass helped keep the soap warm when the container was moved out of the water bath to the counter for filling the mold.
 
I made some progress yesterday, but still have plenty of room for improvement. From left to right, the first soap is from the batch above; the second is colored with the alkanet infused oil added before the cook; the third is colored with a tiny bit of 91% isopropyl alcohol colored by madder that I added before the cook for the light soap (the pigment clumped a bit, but did not seize the batter) and the alcohol was added after the cook for the darker soap. The base batter for the madder soap was on the fluid side, but the darker reddish soap less so. I used a hanger swirl in that one, and got closest to a real swirl near the bottom of the soap, but I also ended up with air pockets.

Issues are:
  • discoloration in the second soap - could this be due to incomplete blending of the lavendar eo? The uppermost layer of soap, which was at the bottom of the container, was mixed a little better compared with the soap that went in below it.
  • ”leafing“ in the second soap - temperature too low?, too much time between getting spoonfuls of soap in the mold? My techniques and rhythm are unpracticed and I think both could be true, but any other critiques/ideas are welcomed.
  • Based on the pink soap, I think I need to start the design process with the soap at a higher temperature and possibly up my water a little. I wasn’t able to measure the temp of the batter for the pink soap just before I started adding it to the mold, but the the temp was just below 170F when I added the eos as the final addition.
View attachment 64634

I’m excited about the way the eos smell in these soaps. They’re really present and bright at 3%. I used lavender again for the second one and grapefruit and bergamot for the soap on the right.

I used the ss cylindrical container posted above for the second batch. It was too tall for good mixing access. I switched to a 1L+ pyrex measuring cup in the water bath for the pink batch, but blended the oils and lye together to light trace in a #5 container before I poured the batter into the glass container. The radiant heat from the heated glass helped keep the soap warm when the container was moved out of the water bath to the counter for filling the mold.
They look good. I think that you know any mistake that you may have made. Easy for someone to come in and critique what you already know. Not so easy to give constructive solutions.
Just be careful who you ask (and what you admit, it may be twisted by wrong intentioned ones).
Well done.
 
Nice! My imagination still has a hard time to grasp OPHP. But the results look promising. That rightmost swirl is already one of the better HP swirls I've seen.
Too bad that the whole keep-HP-fluid-enough-for-proper-swirling story demands so much fine tuning (amount and choice of hard oils, water content, additives…), and HP scales so weirdly (double the batch size and you essentially have to start fine-tuning from the beginning).
  • If it weren't HP, I'd suspect that partial gel had struck the middle one. Not sure if it is really a distribution issue of the EO (I'd assume a different pattern then, not something core-rind like). Oxidation effects/interaction between EO, alkanet, and atmospheric oxygen? In any case, watch it closely over the weeks (& keep us updated 😊), and if you can, cut in half one bar in a week or two.
  • Not sure what you mean with “leafing” – the visibility of plopping layers? IME such things even out over cure time.
  • Oh well, temperature of a HP pot is a vexing thing. I always am under the impression that the soap is burning at the bottom & sides, but cool down nearly to solidification in the middle. IME it doesn't get better at the end (vaseline phase, post-cook additions, moulding). Thermal inertia is a good friend once you get the hang of it (but no earlier).
 
They look good. I think that you know any mistake that you may have made. Easy for someone to come in and critique what you already know. Not so easy to give constructive solutions.
Just be careful who you ask (and what you admit, it may be twisted by wrong intentioned ones).
Well done.
It’s best to have a dispassionate attitude when asking for critiques. I try to. This forum is a great place to seek advice, but on the downside, we can’t hear the tone in the voice, or collect any visual clues from the advisor. I try to always assume positive intent even if someone else seems to be starting from a different place.
 
It’s best to have a dispassionate attitude when asking for critiques. I try to. This forum is a great place to seek advice, but on the downside, we can’t hear the tone in the voice, or collect any visual clues from the advisor. I try to always assume positive intent even if someone else seems to be starting from a different place.
Dispassionate attitude is easy for humble people. But words CAN give away intent if we are edept at reading into them.
But they hurt those from whence they came the most. I came on here thinking that I would find neutral scientists. For most part I did, there are always one or two who spoil the broth.

Dispassionate attitude is easy for humble people. But words CAN give away intent if we are edept at reading into them.
But they hurt those from whence they came the most. I came on here thinking that I would find neutral scientists. For most part I did, there are always one or two who spoil the broth.

No one can let a person down, but themselves.

Anyway,
your soap still looks good. Keep up the great positive work.
 
@HoliHealerz
Can you agree with the statement that you did nothing wrong, hurt nobody, and your unkind experiences lately on SMF were entirely due to others to deliberately misunderstand your entirely positive intent?

You don't have to respond. In my opinion, this thread doesn't deserve to be pulled off-topic and toxified by the hurt egos of some individuals who are craving for negative attention.
 
@ResolvableOwl Thanks for the positive and constructive feedback.

“leafing” is possibly a jargon-ish term used to describe the separation of layers in semi-consolidated clay sediments in marine and estuarine environments. 🤣

If you look near the bottom right of the middle bar, there’s a gap/separation line in the soap. The soap is not sticking together in some spots in that batch. The gap positions somewhat line up from bar to bar which makes me think the soap cooled off too much between a few of the plops. My pouring/plopping was slower and more clumsy for that batch compared with the third one.
 
@HoliHealerz
Can you agree with the statement that you did nothing wrong, hurt nobody, and your unkind experiences lately on SMF were entirely due to others to deliberately misunderstand your entirely positive intent?

You don't have to respond. In my opinion, this thread doesn't deserve to be pulled off-topic and toxified by the hurt egos of some individuals who are craving for negative attention.
People only negatively label others when they are trying to gather supporters and cannot do it through intellect. That is nothing to do with me. Its politics.

People only negatively label others when they are trying to gather supporters and cannot do it through intellect. That is nothing to do with me. Its politics.
Just because I can identify your behavior. Does not mean that I was emotionally affected by it. I refuse to be a part of the game. I'm above political strategies.

I apoligize for this interjection @mobjackbay
 
“leafing” is possibly a jargon-ish term used to describe the separation of layers in semi-consolidated clay sediments in marine and estuarine environments. 🤣
How in the world would that have slipped my mind??? 😄


I think I know what you mean. An association with trying to squeeze together flakes of wet cardboard? And late superfat/EO… only makes things more difficult (slippery). The batter seems to intuitively sense that I want to pour it, and turns from sticky, viscous gel into waxy chunks.
Cooling off (thermal inertia again!) really is an enemy here. Two ideas (that sounds too obvious for that nobody has tried this before): Might it help to pre-heat the mould, and/or CPOP the loaf afterwards?

Gosh, now I feel like I must try that out by myself! But then, I won't oppose against a control group/replica 😉.
 
People only negatively label others when they are trying to gather supporters and cannot do it through intellect. That is nothing to do with me. Its politics.
And the answer is yes. I did nothing to add to it. I know because I was very on intent about seeking knowledge. It wasnt until things comtinued that I recognized that there was something going on. Until then I assumed what I always do, good intent. Somethings cannot be ignored. I'm also not blind. Everything I said was completely twisted and turned around and nothing that you drew a conclusion about was infact the reality.
And so WHAT if I did not have 100 % of the facts, although I still only repeated what I saw on videos and read myself. I kept thanking for information to be peaceful but in reality, the one time that you COULD have given information that I actually could have used...you didnt. So yes. i can say I did nothing to hurt anyone. If anyone was hurt then it was due to their own issues and they need to sort that out themselves.
 
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