[Alt-photo] Re: lump gum

[Jorj Bauer]

Glyoxol is a hardener. You probably don't want to use that as a preservative for gum.

Thymol should work. I'd be surprised if you couldn't find that; it's commonly used as an anti-fungal for finger- and toe-nails.

-- Jorj

On Oct 19, 2013, at 11:40 AM, Laura V <laura at lavatop.com> wrote:

> Thanks for this. I have not used a preservative before (mainly because I don't know where to buy it). I usually just mixed a small batch (when I had the powdered stuff) and kept it in the fridge and used it within 2 weeks.
> 
> Unless, is glyoxol a preservative? I have some that I used in paper sizing. It would be handier to always have the gum pre-mixed.
> 
> Laura
> 
> On 10/19/13 3:01 PM, Guido Ceuppens wrote:
>> Laura,
>> 
>> I used the following procedure with lumps of gum:
>> 
>> 300 grs of gum are slowly dissolved in 850 ml of cold water, this may take
>> several days. The impurities are then filtered or fished out, some
>> recommend to suspend the lumps of gum in a muslin bag to prevent the
>> impurities to float in the solution. Once dissolved a preservation agent
>> must be added to the solution: in the past I have added either 15 ml of
>> formol or 7.5 grs of sodium benzoate. I have used the thus prepared gum for
>> years without it going bad (I mainly use casein now but occasionally use
>> gum that was prepared from powder –same procedure- 7 years ago).
>> 
>> Welcome back and good luck,
>> 
>> Guido
>> 
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