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The main objective of this study was to evaluate the tolerance of stationary phase (STAT) and long-term survival phase (LTS) Salmonella Enteritidis ATCC 13076 to atmospheric cold plasma (ACP) in phosphate buffered saline (PBS, pH 7.0) and on shell eggs. Salmonella Enteritidis was cultured in tryptic soy broth supplemented with 0.6% (w/v) yeast extract (35°C) for 20 h (STAT) and 21 days (LTS). Cell morphology was determined by light microscopy. The PBS and shell eggs were inoculated with STAT or LTS cells to obtain ∼7.0 log10 CFU/mL or egg. The ACP was applied at 45 kV (PBS) and 60 kV (shell eggs) for 1–4 min and 1–5 min, respectively. Pathogen survivors were enumerated on thin agar layer (TAL) medium and on xylose lysine tergitol-4 (XLT-4) agar after 48 h of incubation (35°C). For survivors on shell eggs, R2 and mean square error values were obtained using Log-linear with Tail and Weibull models. The STAT cells were predominantly rod-shaped whereas LTS cells were coccoid. In PBS, reductions (log10 CFU/mL) of STAT cells were 1.0, 0.95, 1.45, and 1.44 after exposure to ACP for 1, 2, 3, and 4 min, respectively. In contrast, reductions in LTS cells were significantly lower (p< 0.05) at 0.04 (1 min), 0.06 (2 min) 0.01 (3 min), and 0.11 (4 min). A similar pattern was observed for shell eggs whereby LTS cells exhibited much higher tolerance to ACP than STAT cells (p < 0.05). The Log-linear with Tail model produced a better fit of the survival data for STAT cells; times to achieve a 4- and 5- log reduction were 5.29 and 5.78 min, respectively. Sub-lethal injury occurred in both STAT and LTS survivors; however, differences were not significant (P > 0.05). Additionally, there were no observed differences in shell strength and yolk color between ACP-treated and control eggs. Based on these results, LTS cells of S. Enteritidis are more tolerant to ACP than STAT cells and should be considered when developing process validation protocols involving application of ACP to inactivate Salmonella on shell eggs.

Pathogens that adapt to environmental stress can develop an increased tolerance to some physical or chemical antimicrobial treatments. The main objective of this study was to determine if acid adaptation increased the tolerance of Escherichia coli O157:H7 to high voltage atmospheric cold plasma (HVACP) in raw pineapple juice. Samples (10 mL) of juice were inoculated with non-acid-adapted (NAA) or acid-adapted (AA) E. coli to obtain a viable count of ~7.00 log10 CFU/mL. The samples were exposed to HVACP (70 kV) for 1–7 min, with inoculated non-HVACP-treated juice serving as a control. Juice samples were analyzed for survivors at 0.1 h and after 24 h of refrigeration (4 °C). Samples analyzed after 24 h exhibited significant decreases in viable NAA cells with sub-lethal injury detected in both NAA and AA survivors (p < 0.05). No NAA survivor in juice exposed to HVACP for 5 or 7 min was detected after 24 h. However, the number of AA survivors was 3.33 and 3.09 log10 CFU/mL in juice treated for 5 and 7 min, respectively (p < 0.05). These results indicate that acid adaptation increases the tolerance of E. coli to HVACP in pineapple juice. The potentially higher tolerance of AA E. coli O157:H7 to HVACP should be considered in developing safe juice processing parameters for this novel non-thermal technology.

U.S. Virgin Islands (USVI) imports more than 95% of its food. Transportation limitations throughout the territory’s supply chain can make temperature control of protein foods challenging for consumers. This study aimed to characterize the beef handling practices used by consumers in USVI to determine any educational needs. Printed and online surveys (n = 620 total) were disseminated in USVI through extension agents and local media sources. Three hundred and thirty-four consumers completed a 30-question food handling questionnaire on consumption patterns and food handling from purchasing to their kitchen. Frequencies and Pearson chi-square tests of independence were performed. Beef ranked second among the different meat types consumed, 92% of consumers bought beef from grocery stores, and 55% removed beef from shelves immediately after entering the store. When shopping, 59.1% of respondents always checked the use-by/freeze-by dates of beef, 46.3% always separated beef from other foods, but only 27.5% always used insulated bags. Eighty-three percent of consumers returned home within 1 h of shopping, 92% took less than 30 min to store groceries in either a freezer or refrigerator (98%) and during power outages, 45.1% maintained cold temperatures of beef. Seventy-two percent of consumers washed their hands for more than 10 s, but 33% of those from households with a vulnerable person did not use soap to wash their hands and dried them with reusable towels. When cooking, 44.6% of consumers thawed beef within the temperature danger zone, 80.1% did not check the temperature of beef for doneness, and 34 respondents cooked hamburgers below 160°F. Future consumer food safety education initiatives in the USVI should address hand hygiene among food preparers in homes with vulnerable persons, temperature control practices by promoting the use of insulated bags, safe meat thawing techniques, and the use of thermometers during cooking.

The main objective of the present study was to determine the efficacy of dielectric barrier discharge (DBD) high voltage atmospheric cold plasma (HVACP) at 70 kV for inactivating Salmonella enterica and shiga-toxin-producing Escherichia coli (STEC) on desiccated shredded coconut. Additional objectives were to evaluate sub-lethal injury in pathogen survivors, and selected quality characteristics of the coconut as affected by HVACP. Shredded coconut inoculated with ∼7.74 log10 CFU/g S. enterica or STEC, was exposed to HVACP (70 kV) for 3–15 min (S. enterica) and up to 5 min (E. coli). Non-HVACP-treated, inoculated coconut served as control. Samples were held at 23 ± 1°C for 24 h after HVACP treatment, and analyzed for survivors via the plate count method using thin agar layer (TAL) media and selective (SEL) agar. For each pathogen, differences in numbers of survivors on TAL medium and selective agar were used to evaluate sub-lethal injury. Color and texture of the coconut were determined using a ColorFlex EZ Spectrophotometer and a TA. XT Plus C Texture Analyzer, respectively. HVACP treatments significantly decreased the initial numbers of viable S. enterica and STEC (p < 0.05) with more survivors consistently recovered on TAL media compared to selective agar. Reductions (log10 CFU/g) of STEC and S. enterica after 3 min of HVACP treatment were 1.97 and 1.56, respectively (p < 0.05) based on survivors on TAL medium. A greater extent of sub-lethal injury was observed in STEC survivors compared to S. enterica (p < 0.05). The TAL method allowed detection of sub-lethally injured pathogens in HVACP-treated coconut that would have otherwise remained undetected if only selective agar media were used. There were minimal changes in color and texture of the coconut after HVACP (70 kV) treatment for 12 min. Based on these results, HVACP (70 kV) has good potential for inactivating enteric pathogens in desiccated shredded coconut to improve the microbial safety of this popular food ingredient with minimal effect on product color and texture.

The United States Military Academy's Chemical Engineering Chocolate Club increases the interest in the sciences by combining chemical engineering knowledge with the production of a consumable product, chocolate. Cadets design the chocolate process by identifying the product (such as 70% dark chocolate), ingredients, and specific process details such as mixing standards and refinement time. They extend their design to include the use of rheology and a range of rheological models for quality control and assurance.

The main objective of this study was to evaluate the tolerance of stationary phase (STAT) and long-term survival phase (LTS) Salmonella Enteritidis ATCC 13076 to atmospheric cold plasma (ACP) in phosphate buffered saline (PBS, pH 7.0) and on shell eggs. Salmonella Enteritidis was cultured in tryptic soy broth supplemented with 0.6% (w/v) yeast extract (35°C) for 20 h (STAT) and 21 days (LTS). Cell morphology was determined by light microscopy. The PBS and shell eggs were inoculated with STAT or LTS cells to obtain ~7.0 log10 CFU/mL or egg. The ACP was applied at 45 kV (PBS) and 60 kV (shell eggs) for 1-4 min and 1-5 min, respectively. Pathogen survivors were enumerated on thin agar layer (TAL) medium and on xylose lysine tergitol-4 (XLT-4) agar after 48 h of incubation (35°C). For survivors on shell eggs, R2 and mean square error values were obtained using Log-linear with Tail and Weibull models. The STAT cells were predominantly rod-shaped whereas LTS cells were coccoid. In PBS, reductions (log10 CFU/mL) of STAT cells were 1.0, 0.95, 1.45, and 1.44 after exposure to ACP for 1, 2, 3, and 4 min, respectively. In contrast, reductions in LTS cells were significantly lower (p< 0.05) at 0.04 (1 min), 0.06 (2 min) 0.01 (3 min), and 0.11 (4 min). A similar pattern was observed for shell eggs whereby LTS cells exhibited much higher tolerance to ACP than STAT cells (p < 0.05). The Log-linear with Tail model produced a better fit of the survival data for STAT cells; times to achieve a 4- and 5- log reduction were 5.29 and 5.78 min, respectively. Sub-lethal injury occurred in both STAT and LTS survivors; however, differences were not significant (P > 0.05). Additionally, there were no observed differences in shell strength and yolk color between ACP-treated and control eggs. Based on these results, LTS cells of S. Enteritidis are more tolerant to ACP than STAT cells and should be considered when developing process validation protocols involving application of ACP to inactivate Salmonella on shell eggs. [ABSTRACT FROM AUTHOR]

Many members of the citrus family (Rutaceae) are valued for the aromatic compounds emitted by their flowers. Ptelea species are unusually cold-hardy members of the Rutaceae, but conflicting descriptions of the fragrance of their unisexual flowers may discourage the use of these trees. We analyzed floral volatiles and human response to these chemicals to test the hypothesis that the fragrance of staminate and pistillate flowers of these species differs. Gas chromatography and mass spectrometry showed that most volatile chemicals emitted by flowers of Ptelea trifoliata and Ptelea crenulata are monoterpenes, sesquiterpenes, and esters. Most volatiles were emitted from flowers of both sexes, but ethyl benzoate and estragole were emitted only from pistillate flowers. When concentrations of aromatics differed between sexes, they were higher for pistillate flowers, except for cis-3-hexenyl butanoate and an unidentified terpene. For P. crenulata and P. trifoliata, respectively, 81% and 77% of survey responses were from volunteers who liked the fragrance. Panelists most frequently described the scent of flowers of P. crenulata of both sexes with the words citrus, lime, and sweet. Panelists distinguished between pistillate and staminate flowers of P. trifoliata, describing the odor of pistillate flowers most frequently with the words damp-earthy, spicy, and sweet; staminate flowers were perceived as light, fresh, grassy, and pleasant. This work represents the first analysis of floral volatiles of P. crenulata and resolves conflicting prior reports regarding the floral fragrance of P. trifoliata. We conclude that differences among people rather than the sex of flowers account for conflicting prior reports of floral fragrance. The scents of flowers of P. crenulata and P. trifoliata appeal to most people and are horticultural assets of these trees.

Pathogens that adapt to environmental stress can develop an increased tolerance to some physical or chemical antimicrobial treatments. The main objective of this study was to determine if acid adaptation increased the tolerance of Escherichia coli O157:H7 to high voltage atmospheric cold plasma (HVACP) in raw pineapple juice. Samples (10 mL) of juice were inoculated with non-acid-adapted (NAA) or acid-adapted (AA) E. coli to obtain a viable count of ~7.00 log10 CFU/mL. The samples were exposed to HVACP (70 kV) for 1–7 min, with inoculated non-HVACP-treated juice serving as a control. Juice samples were analyzed for survivors at 0.1 h and after 24 h of refrigeration (4 °C). Samples analyzed after 24 h exhibited significant decreases in viable NAA cells with sub-lethal injury detected in both NAA and AA survivors (p < 0.05). No NAA survivor in juice exposed to HVACP for 5 or 7 min was detected after 24 h. However, the number of AA survivors was 3.33 and 3.09 log10 CFU/mL in juice treated for 5 and 7 min, respectively (p < 0.05). These results indicate that acid adaptation increases the tolerance of E. coli to HVACP in pineapple juice. The potentially higher tolerance of AA E. coli O157:H7 to HVACP should be considered in developing safe juice processing parameters for this novel non-thermal technology. [ABSTRACT FROM AUTHOR]

Introduction: Early antibiotic administration is recommended in newborns presenting with febrile illness to emergency departments (ED) to avert the sequelae of serious bacterial infection. Although ED crowding has been associated with delays in antibiotic administration in a dedicated pediatric ED, the majority of children that receive emergency medical care in the U.S. present to EDs that treat both adult and pediatric emergencies. The purpose of this study was to examine the relationship between time to antibiotic administration in febrile newborns and crowding in a general ED serving both an adult and pediatric population.Methods: We conducted a retrospective chart review of 159 newborns presenting to a general ED between 2005 and 2011 and analyzed the association between time to antibiotic administration and ED occupancy rate at the time of, prior to, and following infant presentation to the ED.Results: We observed delayed and variable time to antibiotic administration and found no association between time to antibiotic administration and occupancy rate prior to, at the time of, or following infant presentation (P > 0.05). ED time to antibiotic administration was not associated with hospital length of stay, and there was no inpatient mortality.Conclusion: Delayed and highly variable time to antibiotic treatment in febrile newborns was common but unrelated to ED crowding in the general ED study site. Guidelines for time to antibiotic administration in this population may reduce variability in ED practice patterns. [West J Emerg Med. 2013;14(5):518-524.]