Time filter

Source Type

Ayari S.,National Center for Nuclear science and Technologies | Ayari S.,National Institute for Applied science and Technologies INSAT | Dussault D.,Research Laboratory in science Applied to Food | Millette M.,Research Laboratory in science Applied to Food | And 3 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010

Carvacrol and mild heat treatment were tested for their efficiency to increase the radiosensitivity of Bacillus cereus in broth. The bacterium was treated with γ-irradiation alone or in combination with carvacrol at its minimal inhibitory concentration or mild heat treatment for 10 min at 45 °C. The effects of this combination of treatments were studied on various parameters: the bacterial viability, the modifications of the cell morphology with scanning electron microscopy (SEM), the cellular fatty acids composition of the membrane quantified by gas chromatography, the intracellular and extracellular adenosine 5′-triphosphate (ATP) concentrations, and the DNA degradation. Combined treatments resulted in additive or synergistic effects as compared to γ-irradiation alone. A significant modification (P < 0.05) of the fatty acid composition and unsaturation ratios was observed. Pretreatment with mild heat or carvacrol before irradiation disturbed the membrane integrity of B. cereus and induced a significant decrease (P < 0.05) of the intracellular ATP concentration. SEM observations revealed that the cell membrane was more severely affected with combined treatment than irradiation alone. The electrophoresis analysis showed that DNA degradation by combined treatments was greater than the γ-irradiation alone. © 2010 American Chemical Society.

Ayari S.,National Center for Nuclear science and Technologies | Ayari S.,National Institute for Applied science and Technologies INSAT | Dussault D.,INRS Institute Armand Frappier | Jerbi T.,National Center for Nuclear science and Technologies | And 2 more authors.
Radiation Physics and Chemistry | Year: 2012

Minced meat beef inoculated with Bacillus cereus spores was treated with four essential oil constituents. The active compounds were sprayed separately onto the meat in order to determine the concentration needed to reduce by 1. log the population of B. cereus spores. Cinnamaldehyde was the best antimicrobial compound selected. It was mixed with ascorbic acid and/or sodium pyrophosphate decahydrate and tested for its efficiency to increase the relative radiation sensitivity (RRS) of B. cereus spores in minced meat packed under air. Results demonstrated that the radiation treatment in presence of the cinnamaldehyde and sodium phosphate decahydrate increased the RRS of B. cereus spores by two fold. The study revealed also that the irradiation of raw beef meat pre-treated with cinnamaldehyde produced an inhibition of the growth of B. cereus count during refrigerated storage. This technology seems to be compatible with industrial meat processing. © 2012 Elsevier Ltd.

Discover hidden collaborations