Claims
- 1. A method for treating living biological cells, each cell having membrane structures and biological proteins, in a medium having dissolved non-condensing gasses, to effect a persistent alteration in structure, function or chemistry of said biological cells, comprising withdrawing a portion of the dissolved non-condensing gasses from said medium containing said cells and subsequently heating a continuous stream of said degassed medium containing said cells by a temperature of at least 2.degree. C. at subatmospheric pressure with steam which has been heated above an equilibrium condensation temperature, at a heating rate which exceeds a relaxation rate of at least a portion of said membrane structures and which results in said persistent alteration, under such time and temperature conditions which do not thermally denature a substantial portion of said biological proteins.
- 2. The method according to claim 1, wherein said medium is a fluid medium, said continuous stream of degassed medium is provided into a reactor for heating, said heating step comprises heating said medium within said reactor at a heating rate of greater than about 1400.degree. C. per second, and wherein said alteration is to inactivate said cells contained in said fluid medium.
- 3. The method according to claim 2, further comprising the step of atomizing said fluid medium into droplets prior to heating, wherein each droplet is less than about 0.3 mm in diameter.
- 4. The method according to claim 1, wherein the medium is heated to a temperature of at least 5.degree. C.
- 5. The method according to claim 1, wherein the medium is heated to a temperature of at least 10.degree. C.
- 6. The method according to claim 1, wherein the medium is heated to a temperature of at least 20.degree. C.
- 7. The method according to claim 1, wherein the heating rate is at least 1100.degree. C. per second.
- 8. The method according to claim 1, wherein the heating rate is at least 1500.degree. C. per second.
- 9. The method according to claim 1, wherein the heating rate is at least 2000.degree. C. per second.
- 10. The method according to claim 1, wherein the heating rate is at least 5000.degree. C. per second.
- 11. The method according to claim 1, wherein the medium is heated to a temperature below about 75.degree. C.
- 12. The method according to claim 1, wherein the medium is heated to a temperature below about 65.degree. C.
- 13. The method according to claim 1, wherein the medium is heated to a temperature below about 55.degree. C.
- 14. The method according to claim 1, wherein the medium is heated to a temperature below about 45.degree. C.
- 15. The method according to claim 1, wherein the maximum time temperature product of the heating step is less than about 200.degree. C..multidot.seconds over a period of five seconds.
- 16. The method according to claim 1, wherein the maximum time temperature product of the heating step is less than about 200.degree. C..multidot.seconds over a period of four seconds.
- 17. The method according to claim 1, wherein the maximum value of the product of (time).multidot.(temperature in excess of 55.degree. C.) of the heating step is less than about 50.degree. C..multidot.seconds over a period of five seconds.
- 18. The method according to claim 1, wherein the maximum value of the product of (time).multidot.(temperature in excess of 55.degree. C.) of the heating step is less than about 50.degree. C..multidot.seconds over a period of one second.
- 19. The method according to claim 1, wherein the persistent change results in cell death.
- 20. The method according to claim 1, wherein the medium is degassed to no more than 100 torr partial pressure of non-condensing gasses prior to heating.
- 21. The method according to claim 1, wherein the medium is degassed to no more than 50 torr partial pressure of non-condensing gasses prior to heating.
- 22. The method according to claim 1, wherein the medium is degassed to no more than 17 torr partial pressure of non-condensing gasses prior to heating.
- 23. The method according to claim 1, wherein the biological cells are selected from the group consisting of bacteria, intracellular parasites and single-celled organisms.
- 24. The method according to claim 1, wherein the biological cells are bacterial cells.
- 25. The method according to claim 1, wherein the medium is milk.
- 26. The method according to claim 1, wherein the biological cells are genetically engineered cells.
- 27. The method according to claim 1, wherein the medium is atomized into droplets prior to heating.
- 28. The method according to claim 1, wherein the medium is atomized prior to heating into droplets having an average diameter of less than about 0.3 mm.
- 29. The method according to claim 1, wherein the medium is atomized prior to heating into droplets having an average diameter of less than about 0.3 mm, and wherein no more than about 1% of said droplets have a diameter larger than about 0.45 mm.
- 30. The method according to claim 2, wherein said non-condensing gasses are continuously withdrawn from said reactor during said heating step.
- 31. A method for treating living cells in a medium, comprising removing dissolved non-condensing gasses from the medium containing said cells, forming the medium as a stream of droplets, heating said degassed medium droplets containing said living cells by condensation thereon of steam having a higher initial temperature than the droplets, wherein the rapid condensation of steam is not substantially impeded by release of non-condensing gasses from the droplets, and said heating being by an amount and at such a rate which is sufficient to persistently disrupt formed cell components of said living cells under such time and temperature conditions which do not denature a substantial portion of the cellular proteins.
Parent Case Info
This Appln claims the benefit of U.S. Provisional No. 60/017,121 filed Mar. 6, 1996.
US Referenced Citations (26)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2052967 |
Jan 1996 |
RUX |
Non-Patent Literature Citations (3)
Entry |
Heimburg et al. (1994) Biochemistry, 33(32), "Thermotropic Behavior of Dimyristoylphosphatidylglycerol and Its Interaction with Cytochrome C", pp. 9477-9488. |
Sugihara, T.F., Heat Pasteurization of Liquid Whole Egg, Food Technology, (Aug. 1966): 100-107. |
Zhang Qinghua, Engineering Aspects of Pulsed Electric Field Pasteurization, Journal of Food Engineering(1995): 261-281. |