Progress 07/15/24 to 07/14/25

Outputs
Target Audience:Within the first year and the current reporting period, our efforts reached a wide range of audiences involved in the postharvest handling of specialty crops. Through structured interviews conducted during the development and refinement of our validation protocols, the project objectives and goals engaged food safety managers and QA/QC personnel responsible for monitoring water quality and sanitizer levels, as well as individuals overseeing broader food safety programs at the organizational level. These conversations helped ensure that the research approach aligned with commercial practices and allowed for the development of protocols that are both scientifically sound and operationally relevant. Additional audiences engaged during protocol development included academic researchers, extension specialists, and graduate students working in produce safety and postharvest microbiology. As part of our in-field validation efforts to date, we partnered with three commercial apple packinghouses in Michigan and four cherry packinghouses in Washington to evaluate the efficacy of flume water management systems under real-world conditions. These collaborations allowed for direct engagement with personnel, including QA/QC staff and line workers who monitor water quality throughout the operational day, as well as food safety managers who make water management decisions. This real-time interaction created opportunities to learn how sanitizer levels are monitored and adjusted, and what triggers water change-outs or other corrective actions. During in-field sampling in Michigan, we also provided educational opportunities to a graduate student at Michigan State University, who joined the research team in observing how water quality is monitored, how microbial sampling is conducted in a commercial setting, and how those data inform risk mitigation strategies in the packinghouse. This experience contributed to workforce development in postharvest food safety. Following each in-field sampling period, individualized feedback was provided to each participating packinghouse. Through follow-up meetings, we reviewed microbial indicator levels, correlations with water quality metrics, and fluctuations in antimicrobial concentration. Based on each facility's data, tailored management recommendations were provided and discussed. To support broader outreach and industry engagement, we also contributed to the Produce Bites podcast. An episode titled "Validating Postharvest Water Systems to Prevent Cross-Contamination" featured Claire Murphy and focused on considerations behind postharvest water management and why validation of these systems is needed. This platform expanded our reach to growers, packers, educators, and regulators nationwide and provided a practitioner-facing explanation of why flume water validation matters, how to approach it, and what our early results show. Changes/Problems:There were no major changes to the overall project objectives or approach during this reporting period. However, we took advantage of an unplanned opportunity to conduct in-field sampling at three commercial apple packinghouses in Michigan. This work was completed at no additional cost to the project and aligned with our original objectives. It provided valuable supplemental data early in the project and broadened the range of operational conditions captured, ultimately strengthening the validation protocol development. What opportunities for training and professional development has the project provided?Within the first year, this project has supported several professional development opportunities. Graduate students at Michigan State University, along with one undergraduate andgraduate students at Washington State University, participated in in-field sampling at commercial packinghouses. Through this experience, they gained hands-on skills in microbial sampling techniques, water quality monitoring, and postharvest food safety risk assessment within a commercial setting. This opportunity not only enhanced their technical expertise but also provided valuable exposure to industry-relevant research. Additionally, the project team leader--an early-career researcher and extension professional--collaborated across multiple states to refine sampling protocols and discuss strategies for field implementation. These cross-institutional interactions fostered professional growth and strengthened team-based problem solving. The project also supported the development and delivery of a Produce Bites podcast episode, offering team members experience in science communication and stakeholder engagement. Moving forward, extension materials and trainings on conducting in-field validation will continue to provide professional development opportunities for both the research team and industry participants during upcoming project phases. How have the results been disseminated to communities of interest?To date, data and key findings have been shared directly with participants to help them improve their management practices. We also released a Produce Bites podcast episode to share insights with the broader produce safety community. More dissemination is planned, including additional extension materials, trainings, and presentations to engage a wider audience as the project continues. What do you plan to do during the next reporting period to accomplish the goals?During the next reporting period, we will continue in-field data collection at additional commercial packinghouses in Washington and Virginia to further evaluate the draft validation protocol under a range of real-world conditions. These assessments will expand our dataset across different water management systems, helping us refine the protocol's usability and relevance across diverse operational settings. Collected data will be analyzed to identify trends in microbial indicator levels, sanitizer concentrations, and water quality parameters. This analysis will inform refinements to the validation strategy, with the goal of providing clearer recommendations on which measurements are most critical, how frequently they should be collected, and how the data can support decision-making around both cross-contamination risk and water hold time. These refinements aim to ensure the protocol is practical and effective for managing both food safety and water conservation. While most outreach and extension activities are planned for year 3, we will begin finalizing the protocol and developing draft guidance materials, including videos and data sheets that support implementation. Additionally, we plan to submit a manuscript summarizing findings from the Michigan apple pilot study, along with additional manuscripts focused on multistate validation data.

Impacts
What was accomplished under these goals? During this reporting period, significant progress was made across all three project objectives. Under Objective 1, we developed a draft validation strategy for postharvest flume systems by compiling existing scientific literature and incorporating input gathered through structured interviews with food safety managers, QA/QC personnel, and industry partners. These conversations helped identify common practices and operational challenges across different commodities and facilities, ensuring the validation approach is both science-based and applicable under commercial conditions. For Objective 2, we began implementing the draft validation strategy through in-field assessments in three commercial apple packinghouses in Michigan and four cherry packinghouses in Washington. At each site, the validation protocol was applied, and the data collected are now being used to refine recommendations on what measurements to collect and how often. Results were shared directly with each participating facility. Progress was also made toward Objective 3, with initial outreach efforts including the recording of a Produce Bites podcast episode titled "Validating Postharvest Water Systems to Prevent Cross-Contamination." This episode featured Claire Murphy and focused on providing science-based guidance for industry professionals on the importance of water system validation.

Publications