freeze-drying, vbl. n. (Stress variable.)
[freeze v.]
A method of drying foodstuffs, blood plasma, pharmaceuticals, etc. while retaining their physical structure, the material being frozen and then warmed in a high vacuum so that the ice sublimes. So freeze-dried a.; (as a back-formation) freeze-dry v. trans.
| 1944 Nature 22 Apr. 485/2 Many biological materials can be most conveniently preserved..if they are dried from the frozen state. The success of the ‘freeze-drying’ procedure appears to be chiefly related to the fact that the resulting ‘solid state’ prevents the concentration and aggregation of the molecules of protein. 1946 Ibid. 7 Sept. 349/1 Freeze-dried milk benefited from the addition of cystine. 1949 E. W. Flosdorf Freeze-Drying i. 6 In 1933 in the author's laboratory..the first products for actual clinical use were freeze-dried. 1956 Nature 14 Jan. 85/2 Freeze-dried bovine uterine cervical secretions. 1957 Times 11 Nov. 13/1 The new ‘freeze-dried’ BCG tuberculosis vaccine... The virus in this case is live, as opposed to the poliomyelitis virus, which is ‘inactivated’. 1959 Times 24 Sept. 7/3 Officers sample new freeze-dried foods. 1962 Engineering 26 Jan. 133 Freeze-drying, AFD, continues..to hold the imagination with its possibilities for preserving the purity and flavour of perishable foodstuffs. 1962 V. N. Orekhovich et al. in A. Pirie Lens Metabolism Rel. Cataract 325 The solution was dialysed and then freeze-dried. 1963 Daily Tel. 29 Aug. 11/2 The valve came from the body of a man who died..about a month ago... The valve was then ‘freeze-dried’ and stored. 1967 New Scientist 9 Feb. 352/3 More recently, freeze-dried coffee extracts have appeared on the market. |