Pine tar oops

[Woo]

Hi, I made pine tar soap for my father three months ago and it turned out great this time I made it and miss read the amount of pine tar to be added. I added 4 ounces instead of the required 8 ounces. This blunder made my batch of 60 oz lye heavy by .21 /oz. It has crystals on the top. I haven't cut it yet. Should I rebatch to add 4 more oz of pine tar? The recipe has 5%SF. Do I need to worry?
Any comments will be helpful. Thank you.

 

[Obsidian]

Yes, you should rebatch. 4 oz of oil is a lot to leave out.

 

[Woo]

Yes, you should rebatch. 4 oz of oil is a lot to leave out.

Thanks! I thought I had heard some people don't even add pine tar into the 'lye calc' at all. ...I have since unwrapped the loaf of soap. No zap on side or bottom ...but the top, yes!

 

[Obsidian]

Hmm, I've not heard of anyone not running the PT through soapcalc. Its saponifies like any other oil and need to be counted.

 

[DeeAnna]

That's only 5 grams too much lye -- at least that's what my soap calc spreadsheet tells me. If you've used a moderate superfat -- say 5% to 8% -- and assumed your NaOH was 100% pure, I'd say you're okay. Give the soap a generous cure and it should be fine.

The bottom of a soap loaf is the most likely to be lye heavy since lye-water solution usually settles. I suspect the top "zap" you're getting may be from some soda ash. Ash can have a metallic, kinda salty tang that can be mistaken for a tiny zap, especially with a side order of pine tar flavor to further confuse things.

Pine tar does chemically react with lye, but the two don't saponify to create soap. I agree with Obsidian -- it is wise to include the PT when calculating the amount of lye for your recipe.

 

[The Efficacious Gentleman]

I would (and do) also run it through the calc with the pine tar listed.

In this case, where you DID have it listed, it falls in to a different category than not listing it at all.

Run the recipe through the same calc again without the pine tar and look if the lye amount changes.

As for advice now, I think it's been said by the others better than I can

 

[boyago]

Pine tar does chemically react with lye, but the two don't saponify to create soap. I agree with Obsidian -- it is wise to include the PT when calculating the amount of lye for your recipe.

Not to divert the topic or hijack but I am curious, is all pine tar created equal? Or enough for a reasonable value as far as soapcalc goes? It seems like the type of product that wouldn't have set standards or the tightest quality control.

 

[DeeAnna]

None of the saponification numbers used in a soap recipe calculator are accurate in the sense that THIS particular sap value is precisely and always correct for THAT fat. The genetics of the particular plant or animal, the feed or nutrients, the year when harvested, etc. all affect the sap values.

I would agree with you that the pine tar "sap" value (not really a saponification value, but you get my drift!) is probably less accurate than the sap values for commonly used soaping fats (olive, palm, coconut, etc.). But they all vary.