[NHCOLL-L:5638] Answer on request from Karen Morton about Freeze Drier

[Thomas Gütebier]

Please publish this answer to the list [NHCOLL-L:5637] Re: Freeze Drier‏:

Dear Karen,thank you for questioning on freeze dry technique. I do agree with Simon on this matter. It's a wonderful help to prevent abdominal distortion/shrinking and for drying botanical material. During many years I did use this technique at the Natural History Museum in Gothenburg and at the Museums of the city of Malmoe/ Sweden. One must keep in mind that it is somewhat tricky to start up the equipment after such a long time. All conduit-pipes for water/oil and gas/air have to be controlled on gas/air leakage. All valves and connecting parts have to be served and high vacuum grease, rubber hoses and rubber liners should be changed. At least the freezer system has to be checked by a company, specialized on freezing technique, alt. vacuum technique. The larger the outfit the higher the cost to renovate your old equipment! Nevertheless - at the beginning there will be a crucial question on how often you will be able to use this technique in the future. Other questions might be about the space, the room temperature, the noise and the oil exhaust from the air pumping and freezing systems and if there is knowledge and time enough to operate the equipment.In Gothenburg we used dryers from different  companies and with different sizes. One of the driers had not been operated for such a long time as for 30 years! I had been able to restart the equipment without problems and with little money. The technique then worked wonderful. After a while the problem was low interest and that we did not had enough material for vacuum freeze drying at that time. Eventually the space was needed for other purposes why the driers went through the recycling process. Nowadays the museum can get help from the Studio of the Western Sweden Conservator's Trust (SVK) who has one of Scandinavia' s largest and newest equipment in use for drying material of cultural heritage.  An alternative solution for you might be to get help from a company or a museum nearby.     The following publications may give you some further answers on your questio
n:
Phillips, A. & B. (1981): The Art Of Freeze Dry Taxidermy. Alabama. Meryman, H. T. (1960): The Preparation of Biological Museum Specimens by Freeze-Drying. Curator: The Museum Journal, Vol. 3, 1: 5 - 96.Harris, R.H.(1964): Vacuum dehydration and freeze drying of entire biological specimens. Annals and Magazine, Natural History Series 13, 7: 65-74. Further bibliography you will find in:Rogers, P.S. and T. Gütebier (1989): An Annotated Bibliography On Preparation, Taxidermy, And Collection Management Of Vertebrates With Emphasis On Birds. Carnegie Museum Of Natural History, Special Publication No. 15.
Best wishes Thomas Thomas GütebierNatural Sciences Conservator NKF-SSveagatan 27SE-41314 Swedenthogu at live.se


 		 	   		  
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