The Zap Test: A Visual Guide

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OK...I'm completely new to soaping and I had no idea you could zap test that way! All I had heard about zap testing was buying this expensive piece of equipment to do it.
This tutorial not only made me laugh my *ahem* off...it also saved me a truckload of money! (And now my kids will have one more reason to think I'm bat crap crazy...awesome!) :D
 
This may be a silly question, but how strong is the zap supposed to be? Is it a noticeable zap (like the buzzy feeling of a fresh 9V battery) or more of a gentle tingle?

Not that I have a whole lot of batches under my belt, but in the ones I've tested, I've never felt a strong zap. In fact, I'm not sure if what I feel is a tingly sensation, or the sensation of my taste buds screaming, "Noooo, not the soap!"

I guess the question is, will I KNOW it's definitely a zap? Should I cut my next batch a little early, to know for sure what a zap feels like? It's like making myself put a 9V to my tongue to find out if it's fresh or not.
 
I guess it depends on how sensitive your tongue is... :p
The "zap" is definitely noticeable, but in varying degrees...it may feel like a little "bite" or "sting" or it may just burn and tingle a bit. If it's just a little tingle or burn and you're just not sure...like not an "Ouch!" but an "Ew!", wait a few days and try again...sometimes it just needs a little more time to fully saponify (if it's fresh out of the mold). If it's a "jolt", there's something wrong, either measurement or recipe wise, and it needs to be rebatched or otherwise revised.

If there are obvious pockets of "ooze"...DO NOT PUT YOUR TONGUE TO IT! :shock:
If there are obvious crystals either on top or throughout your soap...DO NOT PUT YOUR TONGUE TO IT! :shock:

Just a little FYI, the crystals may be fragrance oil, or they may be lye...and if they are lye and only on the top of the soap, they may be able to be rinsed off, especially if the rest of the soap does not zap. If they are inside the soap...rebatch, baby.
 
so this is how you zap test after making cold process? i have seen the zap test done in hot process before it is put into the mold, but i have been wondering how it is tested when it is cold process. i have never made soap before, but it seems i may be better off trying hot process first, because i can zap test it before it is completely done so i don't ruin my batch.
 
I have officially felt my first zap from my batch of non-gel soap. It's nice and creamy looking, and after unmolding, and cutting I was curious if it would zap after being 3 days in the fridge. YUP. I can now say I know what it feels like!
 
So... If it doesn't ZAP, does that mean your soap is completely saponified? Because I just tested my two day old soap (during cutting) and it didn't ZAP... But I don't really know what it should feel like because that was my first time tasting soap.
 
So... If it doesn't ZAP, does that mean your soap is completely saponified? Because I just tested my two day old soap (during cutting) and it didn't ZAP... But I don't really know what it should feel like because that was my first time tasting soap.
You would know if you got zapped. Trust me.
2 day old soap that isn't lye heavy should not zap. Most of the saponification takes place over the first 48 hours...that can be sped up by gelling your soap or the hot process method. So if you didn't get zapped, your on the right track! ;)

If that's your first time tasting soap, I applaud you. I tasted lots of soap growing up (smartypantsmouth) :Kitten Love:
 
You would know if you got zapped. Trust me.
2 day old soap that isn't lye heavy should not zap. Most of the saponification takes place over the first 48 hours...that can be sped up by gelling your soap or the hot process method. So if you didn't get zapped, your on the right track! ;)

If that's your first time tasting soap, I applaud you. I tasted lots of soap growing up (smartypantsmouth) :Kitten Love:

OK, thank you so much for the info. Please help me understand one more thing... Why am I letting it cure again for 4-6 weeks again (per recommendations everywhere)? Is it simply to dry the bars out so they are hard? Or is there some other chemical process besides saponification occurring?:?:
 
OK, thank you so much for the info. Please help me understand one more thing... Why am I letting it cure again for 4-6 weeks again (per recommendations everywhere)? Is it simply to dry the bars out so they are hard? Or is there some other chemical process besides saponification occurring?:?:

During the curing phase, scientifically speaking: excess water evaporates and the pH will drop a little...anecdotally speaking: soap becomes milder and lather improves, and your soap will last longer in the shower. There's lots of theories out there over whether soap needs a 4-6 week cure...and in my experienced opinion, the answer is yes - CP soap benefits from a 4-6 week cure, and longer is better, especially if you use a high percentage of Olive Oil.
Experiment for yourself: use a soap that is freshly cut (as long as there's no zap) and take notes on how long it lasts, lather, hardness, pH, how your skin feels after use, etc. Then use a soap that has cured for 4-6 weeks and take the same notes, and compare the two.
There are generally no dire consequences to using a soap that hasn't had a good cure (with the exception of a lye heavy soap)...it's more a matter of quality.
 
are there soaps that don't zap at all right after cutting? 2 days ago I made no gel whipped soap and it does zap right now. I hope it will go away.. I'm new to all these..
 
My soaps that gel do not zap after 18-24 hours (once they've returned to their opaque stage after gel) as the gelling speeds up the saponification process (like the hot process method does). If your soap is still zapping after 2 days (most saponification generally happens over 48 hours), it probably will not sort itself out. Post your question along with your recipe as a new thread for more detailed advice.
 
I just learned so much from your post about why to cure! Thank you!! I've gelled every batch so far and wondered why it seemed "ready" so quick. I usually just take the little end piece to try out after a couple of weeks. The rest I'm letting cure.

Also, I've been trying to figure out the zap vs icky soap taste (haven't tasted soap since I dropped the f bomb in the 6th grade :oops: ). So today I touched my tongue to the crock pot before cleaning last night's mess. NOW I get it!!! Hahahaha!
 
I tried the zap test with my HP soap the other day. My first thought was, "Zap? Wth? What if it zaps and I don't notice?". So, apprehensively, I stuck my finger tip on the tip of my tongue and ZAAAPP!!! It definitely does feel like touching the tip of a battery on your tongue. Lol. Glad I got that out of the way...Now I know what to expect from licking a lye heavy soap! ;)

I just want to make sure though..once I soap doesn't 'zap', it's okay to use?
 
I just want to make sure though..once I soap doesn't 'zap', it's okay to use?

Yep, once it stops zapping, it's usable ;)
You can invest in fancy schmancy pH testing equipment to get an exact reading of the pH of your soap, but it really isn't necessary. Most soap tests at around the 10 range after cure. Your tongue is way more sensitive than your skin, so if it doesnt cause pain or sensitivity to your tongue, its unlikely to do so on your skin.
 
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