Source: CLEMSON UNIVERSITY submitted to NRP
ENHANCING MICROBIAL FOOD SAFETY BY RISK ANALYSIS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1000058
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
S-1056
Project Start Date
Jul 9, 2013
Project End Date
Jul 8, 2018
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
CLEMSON UNIVERSITY
(N/A)
CLEMSON,SC 29634
Performing Department
Food, Nutrition, and Packaging Sciences
Non Technical Summary
We will conduct on-farm research, in-plant studies, controlled laboratory experiments and disseminate these findings through workshops and publications (trade journals, popular press and refereed journals). Specific topics include the food safety implications related to organic vs. conventional systems for egg laying, on-farm composting, natural antimicrobials, antimicrobial packaging and modified atmosphere packaging. More specifically, eggs from hens raised in a free-range environment will be compared to eggs from hens raised in a cage system and the effect of an organic diet compared to a conventional feed for levels and prevalence of Salmonella spp. in eggs be determined. Due to consumer perceptions towards free-range and organic food products, this research will help determine the reality of eggs derived from these practices. In a separate research track the investigators will develop biological strategies for controlling Salmonella contamination in rendering processing plants, studying the environmental conditions affecting the thermal inactivation of human pathogens during composting and pathogen regrowth in finished compost, determining the pathogen inactivation during composting under field conditions and quantifying the activity of antimicrobials on food. These studies will assist the food industry in reducing the incidence of foodborne illness. Also, determination of the heat-inactivation models will allow a clearer understanding the patterns of how these bacteria are destroyed by heat will result in better treatments to ensure consumer safety. Finally, inhibition of pathogens in ready-to-eat meat products using various methods in a practical and economical way such as an in-package processing, could contribute to a significant decrease in the incidence of human illness and the attendant costs. The combination of in-package pasteurization with preservatives could also assure the safety and quality of poultry products throughout retail marketing. Other project impacts would include documenting and validating the conditions required to produce a safe ready-to-eat meat. Moreover, evaluating inhibitory agents with thermal treatments coupled with existing modified atmosphere packaging technology for use in reducing pathogens on food products will be useful for gaining acceptance of these processes by regulatory agencies. The methodology generated in our proposed study can be used to develop commercially valid processes that will ensure product safety while maintaining product quality.
Animal Health Component
60%
Research Effort Categories
Basic
20%
Applied
60%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
5013260110050%
5013270110025%
5010330110025%
Knowledge Area
501 - New and Improved Food Processing Technologies;

Subject Of Investigation
3260 - Poultry meat; 3270 - Eggs; 0330 - Wetland and riparian systems;

Field Of Science
1100 - Bacteriology;
Keywords
Goals / Objectives
Risk Assessment: Assess food safety risks in agriculture systems Risk Management: Develop science-based interventions to prevent and mitigate food safety threats Risk Communication: Communicate food safety messages to stakeholders
Project Methods
We will conduct on-farm research, in-plant studies, controlled laboratory experiments and disseminate these findings through workshops and publications (trade journals, popular press and refereed journals). Scientists will evaluate the effectiveness of sanitizing agents and look for alternative agents for sanitizing shell eggs. and evaluate factors impacting the safety of eggs and egg products. We will examine the impact of alternative housing practices on egg quality and safety and compare the microbiological status and quality of eggs produced from hens fed a soy-free and standard soy diet along with free-range and caged environments. The objective is to determine if composting of manure performed in a field setting under uncontrolled environmental conditions will effectively eliminate E. coli O157:H7 and the indicator bacteria E. coli and coliforms throughout compost heaps. Trials will be performed involving duplicate compost heaps constructed on an outdoor, fenced site. The compost heaps will be comprised of dairy manure, hay, feed waste, a sawdust-calf feces mixture, and fresh hay. A multi-hurdle approach using natural antimicrobial films and carriers with in-package pasteurization for sliced ready-to-eat poultry products will be evaluated. Packaging films containing or coated with adsorptive powders containing various natural antimicrobials will be created and subsequently tested for their efficacy againstListeria monocytogeneson ready-to-eat meat products. By increasing the efficacy of the surface pasteurization process using antimicrobials, the probability thatL. monocytogeneswill survive in the product is expected to be greatly reduced or eliminated. An additional benefit that will be collectively explored is determining the impact of these intervention strategies on extending product shelf life.

Progress 07/09/13 to 07/08/18

Outputs
Target Audience: Food microbiologists, food safety officials, food industry,students and thegeneral public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Training of graduate students. How have the results been disseminated to communities of interest?Research was shared through 5 online news articles,10 radio and television interviews,6 poster presentations, 3 oral presentations, 6 refereed journal articles and 2 popular press articles. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Summary of Accomplishments by objective area 1) Risk Assessment: Assess food safety risks in agricultural systems We have optimized a culturing method for detecting non-O157 Shiga toxin-producing Escherichia coli (STEC) in the finished dairy compost. Our results demonstrated that low levels (1- 100 CFU/g) of non-O157 STEC could be detected within two days from dairy compost by a culturing method through the optimized enrichment procedure followed by immunomagnetic bead separation (IMS). In contrast, without an enrichment step, the IMS detection limit of individual non-O157 STEC serovar ranged from 3.15 to 4.15 logs CFU/g in dairy compost. We investigated the survival of Escherichia coli O157:H7 and Salmonella Typhimurium in finished dairy compost with different particle sizes during storage as affected by moisture content and temperature under greenhouse conditions. Our results revealed that finished compost samples with larger particle sizes supported pathogen survival for extended time as compared with compost samples with smaller particle sizes. In addition, for the same particle size, the pathogen survived better in compost with lower moisture content. Under greenhouse conditions, higher dehydration rate was found to be a critical factor contributing to the initial rapid inactivation of pathogens. In consideration of the extended survival of a few pathogenic cells in finished compost particles, the risk of compost bioaerosols as one of the possible sources of produce contamination needs to be further assessed under field conditions. 2) Risk Management: Develop science-based interventions to prevent and mitigate food safety threats We evaluated the effectiveness of a two-step heat treatment for eliminating desiccation-adapted Salmonella spp. in aged chicken litter. The higher initial moisture contents in chicken litter contributed to rapid killing of Salmonella during moist-heat treatment. Based on our results, a two-step heating process consisting of a moist-heat treatment for 1 h at 65°C and a sequential dry-heat treatment for 1 h at 85°C can be sufficient for achieving >5.5-log reductions of Salmonella in chicken litter with moisture content of ≥40%. In order to be used by thechicken litter processing industry, further pilot study of this two-step heat processing is needed. We tested polydiacetylene liposome sensors for response to food sanitizers. These biosensors will be used to detect bacteria in food processing environments thus information interaction with sanitizers is important. Chlorine and iodophores gave no response while quaternary color and alkaline surfactants responded to the PDAs with color change. Inkjet-printed 10, 12-pentacosadyinoic acid (PCDA) vesicles were used to determine the effect of ratio, concentration and exposure time of food plant sanitizers and surfactants on PCDA vesicles response. Vigilquat, TritonX-100 and alkaline electrolyzed water (E.W. alkaline) reacted with PCDA vesicles giving a visible color transition. The best ratio for detecting Vigilquat and TritonX-100 was 1:9 while best ratio for detecting E.W. alkaline was 1:1. PCDA vesicles were sensitive enough to detect relatively low concentrations of Vigilquat (25ppm) and TritonX-100 (0.1%). Reactions started immediately and lasted for several hours. A microbiological investigation on Salmonella contamination was conducted in two rendering plants in order to investigate the potential cross-contamination of Salmonella in rendering processing environment. Among 108 samples analyzed, 79 samples (73%) were Salmonella-positive after enrichment, and the selected Salmonella isolates (n = 65) were assigned to 31 unique PFGE patterns with 16 Salmonella serotypes including Typhimurium and Mbandaka identified as predominant serotypes, and 10 Salmonella strains were determined as strong biofilm formers. Based on our results, raw material receiving area was found as the primary source of Salmonella, whereas the surfaces surrounding crax grinding and the finished meal loading-out areas harbor Salmonella in biofilms that may re-contaminate the finished meals. The same Salmonella serotypes found in both raw materials receiving and the finished meal loading-out areas also suggested a potential of cross-contamination between different areas in rendering processing environment. To reduce the Salmonella spread in the rendering environment, we determined the effectiveness of bacteriophage treatment for reducing Salmonella biofilms and attachment on hard surfaces. Bacteriophages (n = 6) were selected for bacteriophage treatment based on host ranges against Salmonella isolates (n = 10) obtained from rendering plants. The inhibition of biofilm formation and reduction of pre-formed biofilm in 96-well microplate with bacteriophage treatment reached up to 90 and 66%, respectively. Under laboratory conditions, bacteriophage treatment reduced up to 2.9 and 3.0 log CFU cm-2 of attachment and slightly formed biofilm of selected top 10 Salmonella strains and an avirulent Salmonella Typhimurium strain 8243, respectively, as compared with reductions of 3.4, 1.4 and 3.0 log CFU cm-2 of Salmonella Typhimurium strain 8243 in summer, fall/winter and spring seasons under greenhouse conditions, respectively. Bacteriophages were effective on reducing Salmonella attachment and biofilms formed on hard surfaces under both laboratory and greenhouse conditions. Clearly, the use of bacteriophages on hard surfaces may have merits in reducing the likelihood of finished rendered products being re-contaminated with Salmonella in rendering plants. Preservation effects of modified atmosphere package combined with nisin on fresh Atlantic salmon were evaluated. Farm-raised Atlantic salmon were purchased from the local market and packaged using either 19 % CO2 : 70 % N2 : 11 % O2 , 38 % CO2 : 51 % N2 : 11 % O2, and under atmospheric air (with and without nisin at 400 IU/g) resulting in a total of 6 treatments. We found the combination of MAP and nisin could extend the shelf life of raw salmon. 3) Risk Communication: communicate food safety messages to stakeholders General risks of cross contamination were communicated through 5 online news articles and 10 radio and television interviews and through 6 poster presentations, 3 oral presentations, 6 refereed journal articles and 2 popular press articles.

Publications


    Progress 10/01/16 to 09/30/17

    Outputs
    Target Audience:The Target audience includes food microbiologists, food safety officials and the food industry in general. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?We have published the results in scientific journals and presented the results to the redndering industry. What do you plan to do during the next reporting period to accomplish the goals?Continue to publish results in scientific journals and present the results directly to the food processing industry.

    Impacts
    What was accomplished under these goals? Cross-contamination of Salmonella in rendering processing plants continued to be studied in 2017. Salmonella-positive after enrichment, and the selected Salmonella isolates that were assigned to 31 unique PFGE patterns with 16 Salmonella serotypes including Typhimurium and Mbandaka were identified as predominant serotypes, and 10 Salmonella strains were determined as strong biofilm formers. Raw material receiving area was found as the primary source of Salmonella, whereas the surfaces surrounding crax grinding and the finished meal loading-out areas harbor Salmonella in biofilms that may re-contaminate the finished meals. The same Salmonella serotypes found in both raw materials receiving and the finished meal loading-out areas also suggested a potential of cross-contamination between different areas in rendering processing environment. Bacteriophages were effective on reducing Salmonella attachment and biofilms formed on hard surfaces under both laboratory and greenhouse conditions. Clearly, the use of bacteriophages on hard surfaces may have merits in reducing the likelihood of finished rendered products being re-contaminated with Salmonella in rendering plants. Platforms for bacterial sensing based upon polydiacetylene (abbreviated PDA), a unique chromatic polymer are being developed for use in food plants. PDA has attracted significant interest in recent years due to its colorimetric and fluorescence properties. General risks of cross contamination were communicated through 3 online news articles and 4 radio and television interviews.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Gong, C. and X. Jiang. 2017. Application of Bacteriophages to Reduce Salmonella Attachment and Biofilms on Hard Surfaces. Poult. Sci. 96 (6): 1838-1848. doi: 10.3382/ps/pew463
    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Chen, Z., and X, Jiang. 2017. Selection of indigenous indicator microorganisms for validating desiccation-adapted Salmonella reduction in physically heat-treated poultry litter. J. Appl. Microbiol. 122(6):1558-1569. doi: 10.1111/jam.13464
    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Chen, Z. and X. Jiang. 2017. Thermal resistance and gene expression of both desiccation-adapted and rehydrated Salmonella enterica Typhimurium in aged broiler litter. Appl. Environ. Microbiol. 31;83(12). pii: e00367-17. doi: 10.1128/AEM.00367-17
    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Wang, H., M. Dharmasena, Z. Chen, and X. Jiang. 2017. Persistence of non-O157 Shiga toxin-producing Escherichia coli in dairy compost during storage. J. Food Prot. 12:1999-2005. Doi:10.4315/0362-028X.JFP-16-552.
    • Type: Journal Articles Status: Published Year Published: 2016 Citation: Dawson, P., Northcutt, J., Parisi, M. and Han, I. 2016 Bioaerosol formation and bacteria transfer from commercial automatic hand dryers. Journal of Food Microbiology, Safety and Hygiene. 1(2): 108. open access journal
    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Han, Dong, Han, Inyee and Dawson, Paul. 2017: Combining modified atmosphere packaging and nisin to preserve Atlantic Salmon. Journal of Food Research 6(1):22-31.
    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Zhang, Y., Northcutt, J.,Hanks, T., Miller, I., Pennington, W.,. Jelinek, R., Han, I., and Dawson, P. 2017. Polydiacetylene sensor interaction with food sanitizers and surfactants. Food Chemistry. 221:515-520
    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Gong, C. and X. Jiang. 2017. Characterizing Salmonella contamination in two rendering processing plants. J. Food Prot. 80:265-270. Doi:10.4315/0362-028X.JFP-16-210.
    • Type: Journal Articles Status: Published Year Published: 2017 Citation: Chen, Z. and X. Jiang. 2017. Microbiological Safety of Animal Wastes Processed by Physical Heat Treatment: An Alternative to Eliminate Human Pathogens in Biological Soil Amendments as Recommended by the Food Safety Modernization Act: A Minireview. J. Food Protection. 80:392-405.


    Progress 10/01/15 to 09/30/16

    Outputs
    Target Audience:Scientists in the field of food microbiology, students, the food industry and the general public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Undergraduate and Graduate students developed laboratory and research skills to investigate various aspects of food safety. Students also gain experience in written and oral presentation of research in refereed journals and at scientificmeetings. How have the results been disseminated to communities of interest?We have disseminated results through workshops, presentations at scientific meetings and in published journal articles. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

    Impacts
    What was accomplished under these goals? A microbiological investigation on Salmonella contamination was conducted in two rendering plants in order to investigate the potential cross-contamination of Salmonella in the rendering processing environment. Among 108 samples analyzed, 79 samples (73%) were Salmonella-positive after enrichment, and the selected Salmonella isolates (n = 65) were assigned to 31 unique PFGE patterns with 16 Salmonella serotypes. Typhimurium and Mbandaka were identified as the predominant serotypes, and 10 Salmonella strains were determined as strong biofilm formers. Based on our results, the raw material receiving area was found as the primary source of Salmonella, whereas the surfaces surrounding crax grinding and the finished meal loading-out areas harbor Salmonella in biofilms that may re-contaminate the finished meals. The same Salmonella serotypes found in both raw materials receiving and the finished meal loading-out areas also suggested a potential of cross-contamination between different areas in the rendering processing environment. To reduce the Salmonella spread in the rendering environment, we determined the effectiveness of bacteriophage treatment for reducing Salmonella biofilms and attachment on hard surfaces. Bacteriophages (n = 6) were selected for bacteriophage treatment based on host ranges against Salmonella isolates (n = 10) obtained from rendering plants. The inhibition of biofilm formation and reduction of pre-formed biofilm in a 96-well microplate reached up to 90 and 66%, respectively. Under laboratory conditions, bacteriophage treatment reduced up to 2.9 and 3.0 log CFU cm-2 of attachedand slightly formed biofilm of selected top 10 Salmonella strains and an avirulent Salmonella Typhimurium strain 8243, respectively, as compared with reductions of 3.4, 1.4 and 3.0 log CFU cm-2 of Salmonella Typhimurium strain 8243 in summer, fall/winter and spring seasons under greenhouse condition, respectively. Bacteriophages were effective atreducing Salmonella attachment and biofilms formed on hard surfaces under both laboratory and greenhouse conditions. Clearly, the use of bacteriophages on hard surfaces may have merits in reducing the likelihood of finished rendered products being re-contaminated with Salmonella in rendering plants. Preservation effects of modified atmosphere package combined with nisin on fresh Atlantic salmon were evaluated. Farm-raised Atlantic salmon were purchased from the local market and packaged using either 19 % CO2 : 70 % N2 : 11 % O2 , 38 % CO2 : 51 % N2 : 11 % O2, and under atmospheric air (with and without nisin at 400 IU/g) resulting in a total of 6 treatments. We found the combination of MAP and nisin could extend the shelf life of raw salmon.

    Publications

    • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Gong, C. and X. Jiang. Pilot study of applying Salmonella-specific bacteriophages in a rendering processing plant. ASM South Carolina Regional Annual Meeting. April 11, 2015, Furman University.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Gong, C. and X. Jiang. 2016. Bacteriophage Treatment of Salmonella Contamination on Workers Boots in a Rendering Processing Environment. IAFP Annual Meeting, St. Louis, MO.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Dawson, Paul; Pennington, William; Zhang, Yueyuan; Northcutt, Julie; and Hanks, Tim. 2016.Polydiacetylenes in Food Safety. Clemson Research Conference. Watt Center
    • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Zhang, Yueyuan, Han, Inyee, Northcutt, Julie, Hanks, Tim, Pennington, William and Dawson, Paul. 2016. Polydiacetylene sensors interaction with food sanitizers. 2016. SE IFT . University of Georgia-Griffin Campus.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Zhang, Yueyuan, Han, Inyee and Dawson Paul. 2016. Peach skin antimicrobial activity in turkey meat. Poultry Science Annual Meeting. New Orleans, LA.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Northcutt, J.K. Safe food handling of fruits and vegetables. 2015. SC Department of Education, School Food Service Directors, Farm-to-School Program. Columbia, SC. February and September
    • Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Gong, C. and X. Jiang. 2016. Characterizing Salmonella Contamination in Two Rendering Processing Plants. J. Food Prot. (in press)
    • Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Zhang, Y., Hanks, T., Miller, I., Pennington, W., Northcutt, J. Han, I. Jelinek, R., and Dawson, P. 2016. Polydiacetylene sensor interaction with food sanitizers and surfactants. Food Chemistry. Accepted


    Progress 10/01/14 to 09/30/15

    Outputs
    Target Audience:foodmicrobiologists, food safety officials and the food industry in general. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has giventhe opportunity to train undergraduate and graduate students on standard and advanced microbiological seperationand identification methods. How have the results been disseminated to communities of interest?General risks of cross contamination were communicated through twoonline news articles and sixradio and television interviews as well as refereed publications and presentations at scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?We plan to continue to make progress on the objectives and projects currently under way.

    Impacts
    What was accomplished under these goals? We have optimized a culturing method for detecting non-O157 Shiga toxin-producing Escherichia coli (STEC) in the finished dairy compost. Our results demonstrated that low levels (1- 100 CFU/g) of non-O157 STEC could be detected within two days from dairy compost by a culturing method through the optimized enrichment procedure followed byimmunomagnetic bead separation(IMS). In contrast, without an enrichment step, the IMS detection limit of individual non-O157 STEC serovar ranged from 3.15 to 4.15 logs CFU/g in dairy compost. We investigated the survival of Escherichia coli O157:H7 and Salmonella Typhimurium in finished dairy compost with different particle sizes during storage as affected by moisture content and temperature under greenhouse conditions. Our results revealed that finished compost samples with larger particle sizes supported pathogen survival for extended time as compared with compost samples with smaller particle sizes. In addition, for the same particle size, the pathogen survived better in compost with lower moisture content. Under greenhouse conditions, higher dehydration rate was found to be a critical factor contributing to the initial rapid inactivation of pathogens. In consideration of the extended survival of a few pathogenic cells in finished compost particles, the risk of compost bioaerosols as one of the possible sources of produce contamination needs to be further assessed under field conditions. We evaluated the effectiveness of a two-step heat treatment for eliminating desiccation-adapted Salmonella spp. in aged chicken litter. The higher initial moisture contents in chicken litter contributed to rapid killing of Salmonella during moist-heat treatment. Based on our results, a two-step heating process consisting of a moist-heat treatment for 1 h at 65°C and a sequential dry-heat treatment for 1 h at 85°C can be sufficient for achieving >5.5-log reductions of Salmonella in chicken litter with moisture content of ≥40%. In order to be used by chicken litter processing industry, further pilot study of this two-step heat processing is needed. We tested polydiacetylene liposome sensors for response to food sanitizers. These biosensors will be used to detect bacteria in food processing environments thus information interaction with sanitizers is important. Chlorine and iodophores gave no response while quaternary color and alkaline surfactants responded to the PDAs with color change. Inkjet-printed 10, 12-pentacosadyinoic acid (PCDA) vesicles were used to determine the effect of ratio, concentration and exposure time of food plant sanitizers and surfactants on PCDA vesicles response. Vigilquat, TritonX-100 and alkaline electrolyzed water (E.W. alkaline) reacted with PCDA vesicles giving a visible color transition. The best ratio for detecting Vigilquat and TritonX-100 was 1:9 while best ratio for detecting E.W. alkaline was 1:1. PCDA vesicles were sensitive enough to detect relatively low concentrations of Vigilquat (25ppm) and TritonX-100 (0.1%). Reactions started immediately and lasted for several hours.

    Publications

    • Type: Journal Articles Status: Submitted Year Published: 2016 Citation: Yueyuan Zhang, Julie Northcutt, Tim Hanks, Bill Pennington, Inyee Han and Paul Dawson. Polydiacetylene sensor interaction with food sanitizer and surfactants. Food Chem. (submitted)
    • Type: Other Status: Published Year Published: 2015 Citation: Dawson, P.L. and Schanzle, 2015. Is it really ok to eat food thats fallen on the floor. The Conversation, online news website. https://theconversation.com/explainer-is-it-really-ok-to-eat-food-thats-fallen-on-the-floor-45541 Over 1 million reads
    • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Wang, H., M. Dharmasena and X. Jiang. Persistence of non-O157 shiga toxin-producing Escherichia coli in dairy compost during room temperature storage. ASM South Carolina Regional Annual Meeting. April 11, 2015, Furman University.
    • Type: Journal Articles Status: Published Year Published: 2016 Citation: Wang, H., Z. Chen, and X. Jiang. Rapid and sensitive detection of non-O157 shiga toxin-producing Escherichia coli in dairy compost by an optimized culturing method. J. Food Prot. (in press)
    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Chen, Z., H. Wang and X. Jiang. 2015. Developing a two-step heat treatment for inactivating desiccation-adapted Salmonella spp. in aged chicken litter. Foodborne Pathogens & Disease. 12(2): 104-109.
    • Type: Journal Articles Status: Published Year Published: 2016 Citation: Diao, J., Z. Chen, C. Gong and X. Jiang. 2015. Influence of compost particle size on pathogen survival under greenhouse conditions. Foodborne Pathogens & Disease. (in press)
    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Dawson, P.L., Han, I., Bailey, C., Lynn, D., and Martinez-Dawson, R. 2015. Bacterial transfer to beverages during drinking games (beer pong). International Journal of Food Safety, Nutrition and Public Safety. 5(2): 151-161.
    • Type: Journal Articles Status: Published Year Published: 2015 Citation: Alsallaiy, Ibtehal, Han, Inyee, Martinez-Dawson, Rose, Dawson, Paul. 2015. Recovery, survival and transfer of bacteria on restaurant menus. Journal of Food Safety, Article first published online: 27 JUL 2015 | DOI: 10.1111/jfs.12212.


    Progress 10/01/13 to 09/30/14

    Outputs
    Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? The results of this research have been reported in presentations and publications in refereed journals. What do you plan to do during the next reporting period to accomplish the goals? Continue to conduct research on biosensors for food processing environments and on-farm interventions for Campylobacter spp. and Salmonella spp.

    Impacts
    What was accomplished under these goals? The application of liposomes as biosensors stems from the ease which they can be modified to add functional groups to detect the presence of undesirable agents and their natural ability to change color due to external stimuli. It is the ability to decorate the surface with nucleic acids, sugars, antibodies or other functionality that makes liposomes so valuable for drug delivery, biosensing, and cellular imaging. (X. Jiang): A C. jejuni-specific primer set targeting a portion of the hipO gene was developed. The specificity of the newly designed primer pair was verified using five C. jejuni strains and 20 other bacterial strains. Sensitivity was determined to be as low as 1 genome copy/reaction. A total of 73 samples were collected at different sites along the processing line during two visits to ? poultry slaughterhouse and were examined by direct plating onto modified Charcoal Cefoperazone Deoxycholate agar (mCCDA) or after enrichment in Bolton broth followed by plating on mCCDA. The newly developed real-time PCR assay was used to identify the presumptive colonies as belonging to C. jejuni. A real-time PCR assay targeting 16S rRNA was also applied to determine Campylobacter spp. prevalence. Results from the real-time PCR analysis indicated considerable variability in Campylobacter contamination with incidence rates of 72.7 and 27.6% for sampling days A and B, respectively. Campylobacter was isolated from 100% of pre-scalded and pre-eviscerated carcasses on sampling day A. In contrast, on sampling day B the highest number of Campylobacter positive carcasses was recovered after evisceration (60%). The chilling process significantly reduced (P<0.05) Campylobacter population but the percentage of positive samples on sampling day A increased to 80%. All samples collected from processing environment except scalding tank #3, pre-chiller and chiller tanks were 100% positive on day A, whereas no campylobacters were isolated from machinery on sampling day B. Our results revealed the widespread of C. jejuni in poultry processing and proved that the newly developed real-time PCR assay is a simple, specific and inexpensive method for rapid C. jejuni identification. The newly developed PCR method can be easily used in laboratories for reliable and unambiguous identification of C. jejuni in poultry samples.

    Publications

    • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Ivanova, M. and X. Jiang. 2013. Prevalence of Campylobacter spp. on poultry carcasses during processing and in slaughtering environment. Abs. 100th Annu. Mtg. Intern. Assoc. Food Prot., Charlotte, NC, July 28-31.
    • Type: Journal Articles Status: Awaiting Publication Year Published: 2014 Citation: Ivanova, M., R. Singh, M. Dharmasena, C. Gong, A. Krastanov, and X. Jiang. 2014. Rapid identification of Campylobacter jejuni isolated from poultry carcasses during processing and samples from slaughtering environment by real-time PCR. Poultry Sci. (in press)


    Progress 07/09/13 to 09/30/13

    Outputs
    Target Audience: Target audiences reached include researchers in the field and industry personnel through published reseach papers, presentations at meetings and industry workshops. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Drs. Northcutt and Dawson have successfully completed the FDA Seafood HACCP "Train-the-Trainers" program and delivered 3 HACCP workshops in the past 1.5 years. How have the results been disseminated to communities of interest? Results have been dissemintaed through presentations at National and International Meetings, through refereed publications and through workshops. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

    Impacts
    What was accomplished under these goals? For the risk management goal we evaluated the use of natural tenderizing enzymes to reduce the risk of food pathogen growth on meats and combined nisin with MAP to reduce the growth of Listeria monocytogenes. For risk communication 2 HACCP workshops have been delivered in the past year.

    Publications

    • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Parisi, M.A., Izquierdo, K.J., Dawson, P.L., and Northcutt, J.K. 2013. Effect of laying hen production system and level of dietary soy on bone strength and composition. P459 Poultry Science 91 (Supplement 1) Pg 155..
    • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Parisi, M.A., Northcutt, J.K., Smith, D.P., Steinberg, E., Izquierdo, K.J. and Dawson, P.L. 2013. Effect of production system on the microbiological contamination of shell eggs. P460 Poultry Science 91 (Supplement 1) Pg 155.
    • Type: Journal Articles Status: Submitted Year Published: 2013 Citation: Steinberg, E. L., R. M. Dawson, P. L. Dawson and J. K. Northcutt. 2013. Consumer perceptions and purchase decisions of organic and conventional fresh produce. Submitted to the Journal of Food Products Marketing. Taylor and Francis Group; ISSN 1045-4446 (Print), 1540-4102. http://www.tandfonline.com/action/aboutThisJournal?journalCode=wfpm20#.UYLU-MrNmSo