Chemical States of Bacterial Spores: Heat Resistance and Its Kinetics at Intermediate Water Activity
AUTOR(ES)
Alderton, Gordon
RESUMO
Bacterial spore heat resistance at intermediate water activity, like aqueous and strictly dry heat resistance, is a property manipulatable by chemical pretreatments of the dormant mature spore. Heat resistances differ widely, and survival is prominently nonlogarithmic for both chemical forms of the spore. Log survival varies approximately as the cube of time for the resistant state of Bacillus stearothermophilus spores and as the square of time for the sensitive state. A method for measuring heat resistance at intermediate humidity was designed to provide direct and unequivocal control of water vapor concentration with quick equilibration, maintenance of known spore state, and dispersion of spores singly for valid survivor counting. Temperature characteristics such as z, Ea, and Q10 cannot be determined in the usual sense (as a spore property) for spores encapsulated with a constant weight of water. Effect on spore survival of temperature induced changes of water activity in such systems is discussed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=376739Documentos Relacionados
- Chemical States of Bacterial Spores: Dry-Heat Resistance
- CHEMICAL COMPOSITION AND HEAT RESISTANCE OF SOME AEROBIC BACTERIAL SPORES1
- The Influence of Various Chemical and Physical Agencies upon Bacillus botulinus and Its Spores: I. Resistance to Salt
- Mineralization and heat resistance of bacterial spores.
- Heat resistance of the chemical resistance forms of Clostridium botulinum 62A spores over the water activity range 0 to 0.9.