zap test

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Well-Known Member
Jul 18, 2008
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I was wondering how long you should feel the zap on cp soap? evidently, my 13 yo and her girlfriend spent the weekend licking my soaps!!! (she just told it tonight at dinner) she said they of course I had to try and she is right. the soap is about 3 weeks old (i thought that it would be gone by now). Also, I have just tried crockpot soap for the first time last night and it has a little sting!! I thought I was doing it right? soap looks ok, the bars are hard. just not sure what I did or did not do.
I test mine after I cut them. In the crock pot I test it before I put it in the mold. If I get zapped I cook it alittle longer. I have not had any of my CP soap zap me yet (an I'm glad). I had a crockpot one zap me an I cooked it for appox. 5 more minutes tested it again. There was no zap.
My first concern would be did you have to much lye and it would be unsafe based on that.

The saponification process should be over within 24 hours +/- and the rest of the "cure" time is to allow the extra liquid evaporate.

So given the soap is that old, are you sure you didn't get to much lye. What recipe did you use, and how was it measured/weighed. (I hope weighed.) And are you sure your scale is accurate and that you got the correct weight.

I do not believe you should have any zap with soap that is 3 weeks old unless it was lye heavy.

edited to add : oops i re-read your post and if you are doing the crock pot HP method then you should not have any sting when it's done and you put it into the mold. If you do then chances are pretty good that your soap may be lye heavy or you didn't cook it long enough. But the zap should be gone in about 24 hours with CP soap, or even soap that was HP'd but not taken to completeness.
I am using the soap cac. and this is what I came up with:
castor 3 oz
coconut 19 oz
oo 29 oz
crisco 13 oz
lye 9.23 0z
gm23 0z

I add all the gm (frozen) with the lie then add to oils all temps are around 100 when I mix....I use the same recipe for both crock pot and cp. My cp is what I am worried about I dont like the texture on the croc soap (but I just had to try). The zap is not happening right away, you have to leave your tounge about 3 seconds....Is it maybe, I just taste soap?? How dumb would I be??? :oops: Kathleen
Is it possible your weights were off when you weighed your lye?

I have done the tongue test (many times when I did HP soap but not when i do CP soap) and there is a difference between a zap and the nasty tates of soap. (at least I think so)

If you think it's a zap and not just the icky tates of soap then you may want to consider not using it.
I had never thought of testing the cp soap untill it was brought to my attention... and because I had just learned about hp and the test (i had mentioned it in front of my girls) it all just came together that way. I would have never tested the cp but i got worried when they said it zaped them. I went in to panic mode because I was so proud of my first soaps. I have been watching them and using the scraps at the kitchen sink, and of course telling everyone I know( I am like a mother hen!!) Now only to find out 3 weeks latter it's not good......I have a good scale and I'm going to trust it and just hope the soap is just really bad tasting.....but if by chance Im wrong how else would I know? I know this is a lot, sorry Im just upset (till I can figure this out.) Thanks for all the in put Kathleen
What kind of scale do you have. That can make a difference.

I have a postal scale, and I always weigh in grams because it's a lot more accurate. There are 28 grams to the ounce. Because I know this, I always remove the container from the platform and let it zero out and then reweigh it. (adding the weight of the container and the contents together, knowing this before hand to get an accurate weight) Sometimes I need to rezero my scale (turn it off and on again to keep it accurate) but when it weighs it's right on the money. But I don't like adding a bit and letting it auto adjust because that's when i see errors and I know it so I always remove the container, let it zero and reweigh every time. To keep it accurate.

I'm not sure what kind of scale yours is or how accurate it is, some are not accurate. So it's something you may want to check. Five quarters (I'm not sure about the newer state quarters but the older ones) equals 1 ounce, as declared by the US mint.

Using lye heavy soap depends on a lot of things. But mostly just how lye heavy is it. Way back in the old days soap was often lye heavy because they didn't have the technology we do today and it was very harsh on their skin. Many women had red chapped hands from using it constantly. If it was very lye heavy it could give the skin a mild burn or a good case of an irritation.

But the important thing to try and figure out is if it's lye heavy or is it just the icky tastes of soap. A zap will be a definite zing like touching your tongue to a 9 volt battery. (I had never done that either and still haven't.) But there is a difference between the zap of lye and the soapy tastes, which is just terrible, and gagging.

But don't despair, if it is off, consider it a good learning experience. You may also want to consider smaller batches at least until you get the hang of it as well. But it's a lot of fun to do and use and well worth the effort of learning.
I didn't know about the 5 quarter thing, I will try that asap. If it is correct then i will assume it is bad tasting soap!! I bought the scale at costo it is for postage it weighs in grams and oz. I never thought about using grams, good idea. I'll keep you posted and thanks for all your help. Kathleen
just because it's correct doesn't mean there wasn't a problem during the weighing of the lye as I have experienced from time to time. Which is why I add the weight of my container and the lye to get the final weight I need and zero it out after each addition or removal of ingredint from the container. Just to double check to make sure it's correct.

When you do the zap test, is it a distinct zap or tingle or just a gross tates?
it wont zap the second you make contact, you have to hold it for about 3-4 seconds and then a tingle and really really really bad taste. I was thinking I was using all this good stuff like honey, oats, brown sugar at trace it would seem to have a good taste lol...not that i would ever suggest eating (or tasting) soap.
*gulp* it's been a LONG time since I have done a zap test.... but i'm going to go and lick a bar of my soap just for you ...... so i can describe it.....

I've got a bar of HP soap that I made well over a year ago (for some reason it's still sitting on the shelf if my desk) so I'll test that one, and a newer CP bar that I made.

BRB foaming at the mouth i'm sure....
bleck bleck bleck bleck, so i didn't quite foam but here are the results.

When I put my tongue on the bar of HP i made a long time ago tingle no nothing just the unpleastant taste of soap.

When I put my tongue on a bar of CP soap I made on July 13 (i keep detailed records of each batch I make) I had no zap, no tingue just the yucky tates of the soap.

just to take it a step further I used a CP bar that I made on July 29 and once again i set my tongue on a bar and no zap no tingle just the yucky tates of soap.

Please note all soaps that were "tasted" are now set aside for MY USE ONLY.
omg you are to funny!!! I owe you big time :lol: I couldn't even get my husband try (i mean taste) my soap. I guess you being a soaper, you know this is sooooo very important to me. I will be in debt to you for ever!! I did try my scale and 5 quarters = 1oz. But the funny thing is when I weighed in grams each alone weighed 6gm but all 5 = 27gm ?? I think maybe I might return scale and start over. Again, thanks Kathleen