Thermal destruction of bacterial spores immobilized in food/alginate particles

Characterization of Bacillus sporothermodurans IC4 spores; putative indicator microorganism for optimisation of thermal processes in food sterilisation

“…Plates containing either Campden sporulation agar (CSA) (Brown et al, 1984), Fortified Nutrient Agar (FNA) (Mazas, González, López, González, & Martín-Sarmiento, 1995), Nutrient Agar (NA) or commercial mushroom soup with added agar (MSA, with 1.5% bacteriological agar added, pH 6.1) were used as sporulation media to evaluate their ability to achieve heat-resistant spores. They were selected since CSA and FNA are commonly used to produce Bacillus spores and the MSA mimics a food where high heatresistant spores are commonly found.…”

“…Crops of highly heat-resistant, spore-forming bacteria with known D and z values have proven to be an efficient tool to evaluate the impact of heat processes (Brown, Ayres, Gaze, & Newman, 1984). One of the most critical points in using bacterial spores for heat process evaluation is to have a high concentration of spores with a stable heat resistance that is kept unchanged after consecutive sporulations.…”

Effect of the medium characteristics and the heating and cooling rates on the nonisothermal heat resistance of Bacillus sporothermodurans IC4 spores

“…Spores were prepared on Petri dishes of plate count agar (PCA) from (Scharlau, Barcelona, Spain) incubated at 30 C for 24 h. Four pure colonies were taken from this agar plate and suspended in physiological salt solution. Then the agar plates containing Campden Sporulation Agar (CSA; Brown et al, 1984) were inoculated with 0.2 mL of this mixture. After 7 days of incubation at 37 C more than 90% of sporulation rate was achieved, as determined by a phase contrast microscopy (Leica, Wetzlar, Germany).…”

A sterilisation Time–Temperature Integrator based on amylase from the hyperthermophilic organism Pyrococcus furiosus

“…• Microbiological methods, whereby cells or spores of a nonpathogenic organism, with similar temperature-induced death kinetics to the target pathogen, are embedded into alginate beads (Brown, Ayres, Gaze, & Newman, 1984). The beads mimic food pieces in their thermal and physical Innovative Food Science and Emerging Technologies 8 (2007) 63 -72 www.elsevier.com/locate/ifset behaviour and so pass through the process with the food.…”