Is this normal? HP Soap turned yellow

Ale · Apr 17, 2020

Hi, last month I tried making to soap bar with the hot process. I made them with fats that I had in my house, which were olive oil (70 %) and lard (30 %) and no fragranves or essential oils. I don't expect my soap to produce much lather or to smell very fine, but at the moment here is difficult go out and buy ingredients... Anyway, I made them on March the 21 and the two bars were of a perfect white. I put them to cure for four weeks. Today I looked at them and I saw they've turned yellow, but they don't smell rancid.
Do you think it's normal?
I attached two photos so you can have an idea. Thank you.

Todd Ziegler · Apr 17, 2020

I have heard of olive oil turning yellow during the curing process but I don't think they are rancid or bad. What type of olive oil did you use in the recipe and what was your lye to water ratio or percentage?

Ale · Apr 17, 2020

I use a lye with a 28 % of NaOH.
For olive oil, I don't know what to you mean. In Italy we have Extra Virgin oil and Virgin oil which are th best, used for cooking or added to food. And then there's an oil of a lower quality which is simply called "olive oil". Mine is that last one.
Reading other threads about HP I got the idea that maybe I overcooked it. How do you understand when soap's ready? I let it cook for about a hour and a half juat to be sure.

Nona'sFarm · Apr 18, 2020

Ale said:
Reading other threads about HP I got the idea that maybe I overcooked it. How do you understand when soap's ready? I let it cook for about a hour and a half juat to be sure.

When I hot process, I use a double boiler method. I also use a 28% lye mixture when I hot process. I check it every 10 minutes and stir. When it starts to look like vaseline/petroleum jelly, then it is ready - sort of translucent. For the recipes I make, it usually takes 30 - 40 minutes. (mine are generally olive, palm, coconut, & shea butter and I also combine my lye water and oils at a high temperature when I hot process.) I let it cure at least 4 weeks, sometimes longer if it is fairly humid.

I don't know why your soap turned yellow. I have not had that experience.

Ale · Apr 19, 2020

Okay, so I have to check when soap batters is in full gel, and when it is in that condition I put it in the mould? I think that mine took more or less the same time to bacome jelly and translucent (40 minutes), so I probably cooked it too long. Does this ruin the finished soap?
Thank you.

PS: I use the double boiler method too

Arimara · Apr 19, 2020

Ale said:
Okay, so I have to check when soap batters is in full gel, and when it is in that condition I put it in the mould? I think that mine took more or less the same time to bacome jelly and translucent (40 minutes), so I probably cooked it too long. Does this ruin the finished soap?
Thank you.

PS: I use the double boiler method too

No. If anything, if just means your soap is hot soap. as for why it turned yellow- it could be the olive oil. Just cure it longer and see what else happens.

As a side of caution, is your lard from the store or from a farm? I'm not sure it matters unless you rendered it from bacon.