I would like to know who invented the freeze drying process (for
foods) and when it was invented.
 
Thanks.

Dear jbeau-ga,

The use of machines to freeze food and then withdraw the moisture is
known as lyophilization. Freeze drying by natural process was
apparently known to the Peruvian Incas of the Andes who stored their
food in the high mountains of the Andes.

Doctor Thomas A Jennings has written a detailed book on this subject
and he has contributed to an article on inventors.about.com.

He writes that ?there is no real invention of a freeze-dryer. It
appears to have evolved with time from a laboratory instrument that
was referred to by Benedict and Manning (1905) as a "chemical pump".
Shackell took the basic design of Benedict and Manning and used an
electrically driven vacuum pump instead of the displacement of the air
with ethyl ether to produce the necessary vacuum. It was Shackell who
first realized that the material had to be frozen before commencing
the drying process - hence freeze-drying. The literature does not
readily reveal the person who first called the equipment used to
conduct this form of drying a "freeze-dryer".?
http://inventors.about.com/library/inventors/blfrdrfood.htm

If you go to amazon.com you can read several pages of his introduction
to his book where he gives further details of the history of
lyophilization.
Lyophilization: Introduction and Basic Principles (Hardcover)
by Thomas A. Jennings 

This is the main amazon page but use the link further below to access
the introduction where you can read the historical review on pages 1
to 4.
http://www.amazon.com/gp/product/1574910817/103-1476473-0577420?v=glance&n=283155&no=%2A&s=books&v=glance

http://www.amazon.com/gp/reader/1574910817/ref=sib_fs_top/103-1476473-0577420?%5Fencoding=UTF8&p=S00N&checkSum=wnAmxPVCvvH7q6LdYWFIYUXVDe9MmxMl1XlZbA5MBy8%3D#reader-link

The book makes reference to two patents. You can view these by going
to the US Patent Office and typing in their number in the Patent
Number Search section of the Issued Patents (PatFT).
http://www.uspto.gov/patft/index.html


I hope this answers your question. If it does not, or the answer is
unclear, then please ask for clarification of this research before
rating the answer. I shall respond to the clarification request as
soon as I receive it.
Thank you
answerfinder

Search strategy
"freeze drying" invented
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