If I want to add germaben IIE to sugar scrubs

[Ruthie]

I have made the sugar scrubs before and love them. Thought before I make any to sell I should add a preservative. Here is my problem. My sugar scrub recipe is measured in cups and the Germaben IIE needs to be weighed. I thought I'd measure and mix the sugar scrub and weigh it then to see how much to add. But I read it should go in the oil first. So now what do I do? Also, my scales only weigh to each 2 grams. So I'll have to measure the lower end of the recommended amount I guess, to make sure I do not end up with too much. Any feedback would be appreciated.

 

[itunu]

All measurements should be in weight rather than volume so you'll need to convert the volume ones to grams - see http://swiftcraftymonkey.blogspot.co.uk/2009/09/weight-vs-volume.html

So you will need to buy a more accurate scale - this one only costs $7 and goes to 0.1g - http://www.amazon.com/dp/B003C2YHRK/?tag=skimlinks_replacement-20

You can then weigh the cup of sugar to convert from volume measurement to grams (weight measurement).

 

[itunu]

Regarding your question on preservative - you can't use germaben IIe as it's water soluble, not oil soluble (presumably you have no water and emulsifier in your scrub) - http://swiftcraftymonkey.blogspot.co.uk/2010/10/preservatives-germaben-ii.html - this link is to germaben II not the E version but they contain the same INCI.

But if you read my post here where I list advice from various cosmetic chemists from the Society of Cosmetic Chemists linkedin discussion forum - http://www.soapmakingforum.com/showpost.php?p=394366&postcount=9

(Summary: "We don't need to preserve our anhydrous scrubs if they contain salt/sugar as they will be self preserving so long as they don't contain botanical bits. Martin (one of the chemists who responded) made an important point regarding adding a preservative to guard against water being introduced. "There is no point as (a) you need one that is active/soluble in water whilst locked in oil [most preservatives would get partitioned ie locked in the oil and not be able to reach the water] and (b) contamination be in drops and not mixed in evenly so the preservative will not get to it." If you do still want to add a preservative, add optiphen as that's oil soluble (most preservatives are not oil soluble) but do note Martin's comment above, it won't really work !")

You will see from all the cosmetic chemists advice that one is not necessary in an anhydrous scrub where the exfoliant is salt or sugar.

 

[new12soap]

If you are making the solid sugar scrub cubes with sugar, oils, and MP soap, you absolutely do need a preservative. People are constantly dipping wet hands in to get a piece, leaving behind moisture and mold will grow in no time.

I don't recall if it was here or another forum (sorry!), but someone made that recipe with MP soap, and the exact same recipe with fresh CP shreds. They were placed in tupperware-type containers side by side in the bathroom, and every day she opened them, barely touched them with a barely damp hand, and closed them up again. Just to see what would happen. I believe it was within 2 weeks that the MP sugar scrubs had visible mold. The CP soap appeared fine, but I do not believe it was challenge tested. The difference? MP is not nearly as high pH.

When in doubt, always always ALWAYSuse a preservative! And choose one appropriate to the product. As a pp pointed out, Germaben is not for anhydrous products. I use Phenopip, but I believe there are others.

JM2C.

 

[itunu]

Yes as new12 soap pointed out, if the scrub contains water (eg MP) soap then it will need a preservative as it is not anhydrous.

The challenge then is finding the right one - see Martin's comments I posted in my summary above. I have discussed this issue with microbiologists and cosmetic chemists, who advise that parabens containing preservatives (eg phenonip) have a tendency to get partitioned (locked) in the oil so if water is introduced it will not be able to reach it - for more technical and detailed explanation see slides from p12 onwards here - http://www.slideshare.net/jimmmcelroy510/antimicrobial-preservation-overview But if the scrub doesn't contain hardly any oil you should probably be fine.

 

[Ruthie]

Yes, the preservative is to guard against wet hands. But I am confused because the IIe says it is for recipes containing more than 25% fixed oils. I guess I need to go back and read more carefully. Thanks for the input.