Foodborne pathogens in cell suspensions or attached to surfaces can be reduced by electrolyzed oxidizing (EO) water; however, the use of EO water against pathogens associated with poultry has not been explored. In this study, acidic EO water [EO-A; pH 2.6, chlorine (CL) 20 to 50 ppm, and oxidation-reduction potential (ORP) of 1,150 mV], basic EO water (EO-B; pH 11.6, ORP of -795 mV), CL, ozonated water (OZ), acetic acid (AA), or trisodium phosphate (TSP) was applied to broiler carcasses inoculated with Salmonella Typhimurium (ST) and submerged (4 C, 45 min), spray-washed (85 psi, 25 C, 15 s), or subjected to multiple interventions (EO-B spray, immersed in EO-A; AA or TSP spray, immersed in CL). Remaining bacterial populations were determined and compared at Day 0 and 7 of aerobic, refrigerated storage. At Day 0, submersion in TSP and AA reduced ST 1.41 log10, whereas EO-A water reduced ST approximately 0.86 log10. After 7 d of storage, EO-A water, OZ, TSP, and AA reduced ST, with detection only after selective enrichment. Spray-washing treatments with any of the compounds did not reduce ST at Day 0. After 7 d of storage, TSP, AA, and EO-A water reduced ST 2.17, 2.31, and 1.06 log10, respectively. ST was reduced 2.11 log10 immediately following the multiple interventions, 3.81 log10 after 7 d of storage. Although effective against ST, TSP and AA are costly and adversely affect the environment. This study demonstrates that EO water can reduce ST on poultry surfaces following extended refrigerated storage.

Escherichia coli O157:H7-inoculated alfalfa seeds with seed layer thicknesses of 1.02 to 6.25 mm were subjected to pulsed UV light for up to 90 s at a 8-cm distance from the UV strobe. Population reductions higher than 4 log 10 colony-forming units (CFU)/g were achieved. For effect of distance from the UV strobe, seeds with 6.25-mm layer thickness were treated 3 to 13 cm from the strobe. Reductions at shorter distances, such as 60 s at 5 cm (1.93 log 10 CFU/g) and 60 to 90 s at 8 cm (4.89 log 10 CFU/g), were significantly higher (P Յ Յ Յ Յ Յ 0.05). Data from the treatments were used to develop empirical models as a function of distance or layer thickness and treatment time for predicting the population of E. coli O157:H7 during pulsed UV-light treatment. This study demonstrates that pulsed UV light holds promise for eliminating pathogens from alfalfa seeds, and the models developed can be useful predictive tools.

Chemical pretreatment of lignocellulosic biomass has been extensively investigated for sugar generation and subsequent fuel production. Alkaline pretreatment has emerged as one of the popular chemical pretreatment methods, but most attempts thus far have utilized NaOH for the pretreatment process. This study aimed at investigating the potential of potassium hydroxide (KOH) as a viable alternative alkaline reagent for lignocellulosic pretreatment based on its different reactivity patterns compared to NaOH. Performer switchgrass was pretreated at KOH concentrations of 0.5-2% for varying treatment times of 6-48 h, 6-24 h, and 0.25-1 h at 21, 50, and 121 °C, respectively. The pretreatments resulted in the highest percent sugar retention of 99.26% at 0.5%, 21 °C, 12 h while delignification up to 55.4% was observed with 2% KOH, 121 °C, 1 h. Six pretreatment conditions were selected for subsequent enzymatic hydrolysis with Cellic CTec2® for sugar generation. The pretreatment condition of 0.5% KOH, 24 h, 21 °C was determined to be the most effective as it utilized the least amount of KOH while generating 582.4 mg sugar/g raw biomass for a corresponding percent carbohydrate conversion of 91.8%.

Alfalfa seeds inoculated with a five-strain mixture of Escherichia coli O157:H7 were immersed in water containing 4, 8, 10, and 21 ppm of ozone for 2, 4, 8, 16, 32, and 64 min at 4 degrees C. Direct ozone sparging of seeds in water was used as an alternative mode of ozone treatment. Ozone-sparged seeds were also subsequently exposed to heat treatment at 40, 50, and 60 degrees C for 3 h. Populations of E. coli O157:H7 on untreated and treated seeds were determined by spread plating diluted samples on tryptic soy agar supplemented with 50 microg/ml of nalidixic acid. Since E. coli O157:H7 was released from inoculated seeds during treatment with ozone, the rate of release of cells from inoculated seeds soaked in 0.1% peptone water for up to 64 min was also determined. The overall reduction of E. coli O157:H7 on seeds treated with ozonated water without continuous sparging ranged from 0.40 to 1.75 log10 CFU/g (59.6 to 98.2%), whereas reductions for control seeds were 0.32 to 1.03 log10 CFU/g (51.7 to 90.5%). Treatment with higher ozone concentrations enhanced inactivation, but contact time longer than 8 min did not result in significantly higher reductions (P > 0.05). For seeds treated by ozone sparging, a 1.12-log10 CFU/g (92.1%) reduction was achieved using a 2-min contact time, and a 2.21-log10 CFU/g (99.4%) reduction was achieved with a 64-min contact time. The corresponding reductions for control seeds were 0.71 log10 CFU/g (79.5%) and 2.21 log10 CFU/g (99.4%), respectively. Treatment of ozone-sparged seeds at 60 degrees C for 3 h reduced the population to an undetectable level by direct plating (4 to 4.8 log10 CFU/g), although survivors were detected by enrichment. Ozone did not have a detrimental effect on seed germination percentage.

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