Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Mechanism of microwave sterilization in the dry state

Journal Article · · Appl. Environ. Microbiol.; (United States)
OSTI ID:5926300

With an automated computerized temperature control and a specialized temperature measurement system, dry spores of Bacillus subtilis subsp. niger were treated with heat simultaneously in a convection dry-heat oven and a microwave oven. The temperature of the microwave oven was monitored such that the temperature profiles of the spore samples in both heat sources were nearly identical. Under these experimental conditions, they unequivocally demonstrated that the mechanism of sporicidal action of the microwaves was caused solely by thermal effects. Nonthermal effects were not significant in a dry microwave sterilization process. Both heating systems showed that a dwelling time of more than 45 min was required to sterilize 10/sup 5/ inoculated spores in dry glass vials at 137/sup 0/C. The D values of both heating systems were 88, 14, and 7 min at 117, 130, and 137/sup 0/C, respectively. The Z value was estimated to be 18/sup 0/C.

Research Organization:
Baxter Travenol Labs., Inc., Round Lake, IL
OSTI ID:
5926300
Journal Information:
Appl. Environ. Microbiol.; (United States), Journal Name: Appl. Environ. Microbiol.; (United States) Vol. 53:9; ISSN AEMID
Country of Publication:
United States
Language:
English