Patent US3673698A successfully refreshed from Google Patents.
US3673698A
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Process for freeze drying with carbon dioxide
Assignee: ALBERT S GUERARD
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Filing: 1970-11-25
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Granted: 1972-07-04
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Expires: 1990-11-25
Abstract
Abstract A continuous process is provided for the improved freeze drying of an aqueous solution to remove the water by sublimation from ice crystals to produce a dry product which can be reconstituted with water more readily than like products heretofore. Such aqueous solutions comprise coffee or tea syrups, fruit juices, milk, eggs, broths and the like.
Inventors
- 👤 Albert S Guerard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:46
CPC Classifications
F; F26; F26B; F26B5/00; F26B5/04; F26B5/06; F26B5/065; A; A23; A23F; A23F5/00; A23F5/24; A23F5/28; A23F5/32
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
95 words
A process as in claim 1, wherein the crystals in the second zone form a bed in such second zone and dry carbon dioxide gas is passed upwardly through the bed of crystals to maintain the bed in a fluidized condition, the temperature and vapor pressure of the injected carbon dioxide being effective to cause sublimation of ice and solid carbon dioxide in the crystals, said temperature of injected carbon dioxide gas being insufficient to thaw the frozen solid residue of the infusion, and recovering the frozen solid residue free of water and carbon dioxide.
Claim 2
Dependent Claim
96 words
A process as in claim 1, wherein the carbon dioxide vapor in the first zone is removed, dried and then returned to the second zone wherein the dry carbon dioxide gas is passed upwardly through the bed of crystals to maintain the bed in a fluidized condition, the temperature and vapor pressure of the injected carbon dioxide being effective to cause sublimation of ice and solid carbon dioxide in the crystals, the temperature being insufficient to thaw the frozen solid residue of the infusion, and recovering the frozen solid residue free of water and carbon dioxide.
Claim 3
Dependent Claim
146 words
The process of freeze drying material comprising: a. mixing an aqueous liquid infusion of the material to be freeze dried with an inert, nonreactive, nontoxic, normally gaseous material at a temperature and a first pressure whereat the mixture of the liquid infusion and the normally gaseous material is a liquid; b. discharging the liquid mixture of normally gaseous material and liquid infusion into a first zone and freezing the liquid mixture in said first zone to produce solid crystals of said normally gaseous material and the liquid infusion; c. and transferring the solid crystals of normally gaseous material and liquid infusion to a second zone maintained at a pressure and temperature whereat the normally gaseous material and the water in the solid crystals sublime to leave a solid residue of the infusion free of water and said normally gaseous material to thus freeze dry said material.
References Cited (Backward Citations)
US1976204A
Cited
US3313032A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |