I found a loaf of castile soap that I know is over a year old. It could be two, I’m just not sure. It was in a plastic “clamshell” which may have slowed it’s curing. I almost never use plastic. I bought these for a soap class I offered and had leftovers that I used for this castile when I ran out of mold space. Because it was an odd shape I tossed it in the back of a shelf and forgot about it.
This soap was made from Costco Pure Olive oil and it was cold processed, around the time that I had an issue with DOS on my castile soap. This is probably not the same batch, but the same time period. All the castile from that time had some yellow/brown spots on them (called DOS for dreaded orange spots). Supposedly this is caused by rancid oil but I have never believed that. It doesn’t make sense. I think it may have been caused by how I stored them and either let them touch metal or wood. I may test this theory in the future but for now I’m advising caution on placement for curing. It is beautifully white all over.
The first interesting note about this soap is the amount it shrank in a year or so. It’s hard to tell looking at soap bars how much they have shrunk unless you weigh them before and after. My labels get loose but that’s not a very clear measurement. This shows exactly how much it shrunk. There is about a scant eighth of an inch at the end of the mold, maybe even 3/32 of an inch. Not a whole lot.
Since I had it here and I have some newer I thought I’d run a test like Jade did. She had a lot more soaps but I had two. The second is from January 10, 2015. It is made with a pomace olive oil from webrestaurantstore. It was hot processed. I used it the day after I made it and I already liked it a lot then. At the time of this test it is 10.5 weeks old.
I took similar pictures of each soap. The older soap actually had more “glycerin strings” though I don’t think we got them in the pictures. They are very similar but in my opinion the newer soap is clearly superior feeling. This isn’t necessarily having to do with age since two different oils were used.
You can watch the video here