Effect of the wavelength of infrared heaters on the inactivation of bacterial spores at various water activities.

摘要: Bacterial spores (Bacillus subtilis subsp. NBRC 16183) inoculated onto a stainless steel Petri dish and treated at nine levels of water activity (a(w)) for 2 days were inactivated by infrared radiation heating (IRH) using three kinds heaters with different spectra. The peak wavelengths used 950, 1,100 1,150 nm. In general, the inactivating efficacy IRH treatment against bacterial shorter wavelength heater (950 nm) was greater than that other heaters. decimal reduction times (D value) calculated linear portion survival curves affected both initial a(w) values spectra rays. Spores approximately 0.9, 0.7 0.6 most resistant to nm, respectively. led maximum D increased as shortened. Optimum identified inactivation IRH. Spore resistance could also be spectral characteristics absorption, which varied spores.