Results 251 to 260 of about 698,622 (299)

Sublimation Freeze-Drying without Vacuum

Science, 1959
Analysis of the freeze-drying procedure shows that the passage of water vapor from the drying boundary through the dried shell is facilitated primarily by the vapor pressure gradient rather than by the absolute pressure of the system. This is experimentally confirmed, and a device for freeze-drying at atmospheric pressure is described.
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Rapid vacuum freeze‐drying of meat

Journal of the Science of Food and Agriculture, 1958
AbstractFreeze‐drying carried out in conventional equipment is a slow process, the rate of drying being limited by the rate of transfer of heat of sublimation. A method is described to carry out rapid freeze‐drying of meat or other foodstuffs by laying the pieces between heater plates fitted with metal spikes which conduct heat uniformly and ...
C. Brynko, W. R. Smithies
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Freeze‐drying using vacuum‐induced surface freezing

Journal of Pharmaceutical Sciences, 2002
A method of freezing during freeze-drying, which avoids undercooling of a solution and allows growth of large, dendritic ice crystals, was investigated. Aqueous solutions of mannitol, sucrose, or glycine were placed under a chamber vacuum of approximately 1 mbar at a shelf temperature of +10 degrees C.
Martin, Kramer, Bernd, Sennhenn, Geoffrey, Lee   +2 more
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Freeze drying - vacuum sublimation

Journal of Scientific Instruments, 1951
A short account is given of the principles involved in the dehydration of heat sensitive materials by sublimation from the frozen state. References are made to drying rates and important design features of commercial apparatus.
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EFFECTS OF HEATING METHODS ON VACUUM FREEZE DRYING

Drying Technology, 1997
ABSTRACT The heat and mass transfer during freeze drying of raw beef by different heating methods is studied theoretically and experimentally. The difference between radiant heating and microwave heating in freeze drying process has been analyzed. The results obtained are important for the selection of the heating methods in practical freeze dryers.
Zhao Hui Wang, Ming Heng Shi
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Modeling of Vacuum Desorption in Freeze-Drying Process

Drying Technology, 2005
Abstract A mathematical model of multicomponent vacuum desorption, which occurs in vacuum freeze-drying process, was developed. In freeze-drying porous biomaterials and pharmaceuticals are considered and the vacuum freeze-drying process, especially the moisture desorption in its final stage, is investigated.
J. F. Nastaj, B. Ambrożek
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Vacuum-Induced Nucleation as a Method for Freeze-Drying Cycle Optimization

Industrial & Engineering Chemistry Research, 2014
A new method using vacuum-induced nucleation to control the freezing process as a means of reducing the freeze-drying cycle and promoting batch homogeneity is proposed. Emphasis was also given to the primary drying stage performed by using in-line monitoring and control.
ODDONE, IRENE, PISANO, ROBERTO, Bullich R., Stewart P.   +3 more
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Vacuum techniques in freeze-drying pilot plants

Vacuum, 1967
Abstract Pilot plant scale operations are described in relation to the process requirements of the freeze-dried food industry. The principles of the freeze-drying process are outlined with examples of the currently available equipment and some techniques of product evaluation from the points of view of process economy and marketing feasibility.
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A comparison between vacuum freeze-drying and atmospheric freeze-drying

1990
International ...
Wolff, Estelle, Gibert, Hugo
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