~*~ SMF January 2018 Challenge- Hidden Heart Swirl! ~*~
~ Last Look At November 2017 Challenge Photos~



Help Support Soapmaking Forum by donating using the link above or becoming a Supporting Member.
Soap Making Forum > The Soap Making & Craft Forum > Lye-Based Soap Forum > DOS and metal (dreaded orange spots and wire racks) ...
Reply
 
Thread Tools
Old 12-30-2017, 11:26 PM   #11
SaltedFig
 
SaltedFig's Avatar
 
Join Date: Feb 2017
Location: Australia
Posts: 588
Liked 599 Times on 285 Posts
Likes Given: 716

Default

Quote:
Originally Posted by psfred View Post
Instant corrosion of the copper, it's not something I'd put on or in soap for that reason. The bad news is that copper, like any polyvalent metal ion, with greatly accelerate oxidation of the fatty acids.

Use copper colored mica next time, I think!

If you are lucky, the color isn't rancid fats (you would smell them by the time they get that dark I suspect) and is just some copper complex that goes reddish orange. The green was copper salts of fatty acids, which started forming as soon as the copper contacted the soap.
Thanks psfred. Yes, this copper powder was part of a series of things that shouldn't be put in soap, from my thread Playing with colours that shouldn't be put in soap (some do not belong anywhere near oxidizing agents! ).

Still lots of fun, but no, not something to add to a "real" bar of soap!

I still reckon it will get rancid. Surprises me that it isn't already, really. Maybe the charcoal powder helps? Don't know. Probably won't test to find out (unless it niggles me too much and I have to know ).


__________________

SaltedFig is offline  
 
Reply With Quote
Old 12-30-2017, 11:47 PM   #12
DeeAnna
SOAP_SUPPORTER.png
 
DeeAnna's Avatar
 
Join Date: Feb 2013
Location: Iowa USA
Posts: 8,567
Liked 11544 Times on 5230 Posts
Likes Given: 5156

Default

A member who has not posted anything of late - topofmurrayhill -- made an edge beveler, if I remember correctly. TOMH used a piece of copper or brass (an alloy of copper) to make a guide that the soap rubbed against as it was pushed through the beveler. You could see the crisp stripe of DOS on the edges of the soap right where the bar touched guide. Not sure how long it took for the DOS to show up, but it was a good lesson to learn about avoiding anything with copper and similar metals when working with soap.


DeeAnna is offline  
2
People Like This 
Reply With Quote
Old 12-31-2017, 12:45 AM   #13
cmzaha
Supporting Member
SOAP_SUPPORTER.png
 
Join Date: Sep 2011
Location: Southern California
Posts: 6,654
Liked 5123 Times on 2972 Posts
Likes Given: 1395

Default

I line my chrome racks with grease resistant sandwich wrap and I have never had a problem with my soaps and have been using these racks for a few years now. If I accidentally let a soap hit an uncovered edge I will end up with a spot
__________________

cmzaha
No kids in the soaping area
cmzaha is offline  
SaltedFig Likes This 
Reply With Quote
Old 12-31-2017, 12:53 AM   #14
scard
 
scard's Avatar
 
Join Date: Jul 2017
Posts: 93
Liked 26 Times on 16 Posts
Likes Given: 92

Default

If I were to use aluminum cookie cutters for imbeds, etc.would they also turn orange eventually?
__________________
Double, double toil and trouble; Fire burn and caldron bubble.
scard is offline  
 
Reply With Quote
Old 12-31-2017, 02:59 AM   #15
SaltedFig
 
SaltedFig's Avatar
 
Join Date: Feb 2017
Location: Australia
Posts: 588
Liked 599 Times on 285 Posts
Likes Given: 716

Default

Quote:
Originally Posted by scard View Post
If I were to use aluminum cookie cutters for imbeds, etc.would they also turn orange eventually?
Not sure. I've had soap batter react very strongly with aluminium, but have never tried cutting cured soap with an aluminium cutter.

In my lay-person opinion, I would suspect that there would be some reaction (due to the high pH of fresh soap), but I don't think it would be as bad as the copper is. I don't know whether it would be enough to trigger DOS. Hopefully psfred might pop back with some ideas on that.

I would still suggest that you exchange your aluminium cookie cutters for another material, such as plastic or acrylic.
__________________

SaltedFig is offline  
 
Reply With Quote
Old 12-31-2017, 01:50 PM   #16
psfred
 
Join Date: May 2017
Posts: 176
Liked 224 Times on 99 Posts

Default

Aluminum doesn't change oxidation states as easily as iron or copper, so it would be less likely to promote DOS, but I'd not bet money on that.

What I can assure you is that you aluminum cookie cutters will start to corrode fairly rapidly, even if you wash them quickly. I'd use stainless steel (not tinned carbon steel) or plastic ones.
psfred is offline  
2
People Like This 
Reply With Quote
Old 01-01-2018, 03:16 PM   #17
earlene
Grandmother & Soaper
SOAP_LIFETIMESUPPORTER.png
 
earlene's Avatar
 
Join Date: Apr 2016
Location: Western Illinois, USA
Posts: 2,453
Liked 2455 Times on 1235 Posts
Likes Given: 1889

Default

Aluminum Foil deteriorates VERY quickly when soap batter falls onto it. I always keep a pizza pan in the oven covered with heavy duty Aluminium Foil to collects spills of any foods that may be messy when cooking. I place casserole dishes on the pizza pan to prevent spills from getting my oven dirty.

One time when CPOPing, I forgot to put a cardboard liner under the soap mold and some soap batter managed to spill out onto my Aluminum covered pizza pan which I had moved to the rack below. When I opened the oven to check on the soap, I discovered not only had the lye eaten through the aluminum foil, it had begun to eat through the pizza pan as well.
earlene is offline  
2
People Like This 
Reply With Quote
Old 01-04-2018, 01:40 AM   #18
GreenDragon
 
GreenDragon's Avatar
 
Join Date: Aug 2017
Location: Austin, TX
Posts: 41
Liked 85 Times on 24 Posts
Likes Given: 2

Default

I also have a wire shelf to store / cure my soaps. I have tried two different liners with great results. My first shelf I lined with cardstock I got from Office Depot. Nice thick white paper that let's the soap breath while curing and protects at the same time. Think it was $10 for 100 sheets.

The other thing I tried with equal success was rolled construction paper you can buy at the hardware store. It's the heavy brown paper you roll out in your house to protect the floor during moves or upgrades. Also very inexpensive at around $15 for 3ftX40ft roll.

Happy soaping!
__________________
I like most animals better than most people.
GreenDragon is offline  
SaltedFig Likes This 
Reply With Quote
Old 01-04-2018, 03:08 AM   #19
DeeAnna
SOAP_SUPPORTER.png
 
DeeAnna's Avatar
 
Join Date: Feb 2013
Location: Iowa USA
Posts: 8,567
Liked 11544 Times on 5230 Posts
Likes Given: 5156

Default

Quote:
Originally Posted by psfred View Post
Aluminum doesn't change oxidation states as easily as iron or copper, so it would be less likely to promote DOS, but I'd not bet money on that....
From a research paper I read today, copper tops the list as the Bad Boy of Rancidity followed closely by lead and iron (not saying people would use lead stuff for soaping, just passing info along), then zinc, followed last by tin and aluminum.

Exposing fat to any of these metals increased the rate at which the fat became rancid compared to fat without any metal. That means it's not a good idea to let any metal touch your soap if you want to avoid DOS/rancidity. But aluminum was low on the list of these troublemakers.
DeeAnna is offline  
 
Reply With Quote
Old 01-04-2018, 06:21 AM   #20
SaltedFig
 
SaltedFig's Avatar
 
Join Date: Feb 2017
Location: Australia
Posts: 588
Liked 599 Times on 285 Posts
Likes Given: 716

Default

Do you have a link please ?

Hopefully that will be a more concise read than The Mechanisms and Factors for Edible Oil Oxidation paper, which did give a lot of information that was interesting, but wasn't so much about listing the metals in order of effect. They too singled out contact with copper as being a cause.

Quote:
Originally Posted by DeeAnna View Post
From a research paper I read today, copper tops the list as the Bad Boy of Rancidity followed closely by lead and iron (not saying people would use lead stuff for soaping, just passing info along), then zinc, followed last by tin and aluminum.

Exposing fat to any of these metals increased the rate at which the fat became rancid compared to fat without any metal. That means it's not a good idea to let any metal touch your soap if you want to avoid DOS/rancidity. But aluminum was low on the list of these troublemakers.
While I agree in general, I would add that carefully selected grades of stainless steel can safely be used directly in contact with lye (and soap batter) during the manufacture of soap.


__________________

SaltedFig is offline  
 
Reply With Quote
Reply


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Drying soap on wire racks taboo? hozhed Lye-Based Soap Forum 12 04-20-2015 07:41 PM
DOS - Dreaded Orange Spots - let's track the cause! RogueRose Lye-Based Soap Forum 14 12-20-2014 04:42 AM
Dreaded Pink Spots? Crocoturtle Lye-Based Soap Forum 5 02-27-2013 02:09 AM
dreaded stearic spots Shar Lye-Based Soap Forum 10 10-28-2011 07:37 PM
dreaded RED spots? phpworm Lye-Based Soap Forum 13 10-05-2009 11:37 PM



Newest Threads