Sturgeon glue and matte paint

Jennifer Cheney <jcheney<-a t->primus< . >ca> writes

>For 4-5 years, I have been experimenting with the preparation and
>use of isinglass from raw sturgeon air bladders obtained from a
>fishery in New Brunswick, Canada.  See
>
>    <URL:https://www.acadian-sturgeon.com>
>
>Due to dwindling supplies of both dried collagen and fully processed
>isinglass sheets obtained through European sources, and recent
>legislation that has banned the import of this material into Canada,
>conservators here can no longer obtain it easily, even at high cost.
>We need to investigate alternative sources of the glue from our own
>waters. ...

Help is at hand.  Isinglass does not come only from sturgeon; in
Canada it can also be made from the swim sounds (air bladders) of
hake, cod, squeteague, tile fish, carp, and catfish.

Living as I do, near the Columbia River, sturgeon bits are available
to me.  I have made isinglass from their swim sounds as well as from
catfish air bladders.

It is not difficult.  The swim sounds are separated from the
entrails while cleaning the fish, rinsed in water, split open to
begin drying, and when they are nearly dry the outer, dark membrane
is stripped off and the remainder is allowed to dry until needed.

Cut up into small bits and put into water for a good soak, it is
cooked for a time.  Any fats float and is skimmed off; any other
matter simply drops down to the bottom of the cooking pan.

The glue water is poured out to cool; (I use a Teflon-coated coated
cookie sheet which has never been used for anything else) when it
gels it can be cut into small squares/rectangles which are set aside
to dry (use a plastic knife).

I dry the gel squares on well-washed fiberglas window screening.

If the dried glue is not water-clear, or nearly so, something was
wrong with the operator's technique.

Another source of isinglass is from shops which sell supplies to
wine and beer makers.

It comes in tinfoil packets and is used to 'fine' wine and beer.

I used it once just to try it out, and it worked... fine.

A good source of information is Robert H. Bogue's book: The
Chemistry and Technology of Gelatin and Glue, McGraw-Hill Book Co.,
Inc.  New York, 1922.

Jack C. Thompson
Thompson Conservation Laboratory
Portland, Oregon
USA


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                  Conservation DistList Instance 27:41
                  Distributed: Friday, April 25, 2014
                       Message Id: cdl-27-41-004
                                  ***