This paper describes the use of log-linear energy phase-space projections to analyze microwave-assisted inactivation bacteria and viruses under different fomite conditions within multimode microwave ovens. The ovens are operated at a cavity-magnetron frequency 2.45 ± 01 GHz. Porous fomites (moist face towels, cotton swabs, kitchen sponges, scrubbing pads, cigarette filters N95-like respirators)...

MODELING THE EFFECT OF WATER ACTIVITY ON THERMAL RESISTANCE OF SALMONELLA IN WHEAT FLOUR By Danielle F. Smith Salmonella is able to survive in low-moisture environments, is known to be more heat resistant as product water activity decreases, and recently has been implicated in several outbreaks and/or recalls associated with low-moisture foods. Therefore, the specific objectives were to: (1) Ev...

Thermal processing of the key lime juice leads to the inactivation of pectin methylesterase (PME) and the degradation of ascorbic acid (AA). These changes affect directly the cloud stability and color of the juice. In this study, an artificial neural network (ANN) model was applied for designing and developing an intelligent system for prediction of the thermal processing effects on the physico...

Thermal inactivation experiments were carried out to assess the utility of a recently optimized phage amplification assay to accurately enumerate viable Mycobacterium avium subsp. paratuberculosis cells in milk. Ultra-heat-treated (UHT) whole milk was spiked with large numbers of M. avium subsp. paratuberculosis organisms (10(6) to 10(7) CFU/ml) and dispensed in 100-microl aliquots in thin-wall...

This work deals with the determination of the inactivation kinetics of several enzymes, most of them used as time-temperature integrators in the food industry. The tested enzymes were polyphenoloxidase, lipoxygenase, pectinase, alkaline phosphatase, and -galactosidase, and the inactivation assays were performed under conventional and ohmic heating conditions. The thermal history of the samples ...

Electrical heating has been proposed as a potential method for pathogen inactivation in human waste sludge, especially in decentralized wastewater treatment systems. In this study, we investigated the heat production and E. coli inactivation in wastewater sludge using electrical thermal treatment. Various concentrations of NaCl and NH4Cl were tested as electrolyte to enhance conductivity in slu...

polyphenol oxidase (ec. 1.10.3.1 ppo), an ionically unbound and thermostable enzyme, was extracted from the leaves of cinnamomum tamala having aroma flavor used to add in indian food and vegetables as a part of spices to enhance the taste of recipes. the enzyme was purified 2.63-fold with a total yield of 9.5% by ammonium sulfate precipitation followed by sephadex g-100 gel filtration chromatog...

immobilized lipoamide dehydrogenase in 30 % (v/v) dioxan. The rate constants for inactivation in dioxan, like those for thermal inactivation at 90°C, increase with increasing distance from the matrix and eventually approach that for the inactivation of the native enzyme in 30% (v/v) dioxan, i.e. 0.01 min-'. These data can be rationalized by the fact that the hydrophilic Sepharose matrix probabl...

Pectin methylesterase (PME) was extracted from bananas and purified by affinity chromatography. The thermal-high-pressure inactivation (at moderate temperature, 30-76 degrees C, in combination with high pressure, 0.1-900 MPa) of PME was investigated in a model system at pH 7.0. Under these conditions, the stable fraction was not inactivated and isobaric-isothermal inactivation followed a fracti...