Risky Business? Conducting a risk assessment of postharvest operations using washing machines for leafy greens​​

Principal Investigator/Project Leader: 
Amanda
Kinchla
Extension Professor
Co-Principal Investigator/Co-Project Leader: 
Mathew
Moore
Assistant Professor
Sponsoring Unit(s): 
UMass Extension
Department of Project: 
Food Science Dept.
Project Website: 
​​​Risky Business? Conducting a risk assessment of postharvest operations using washing machines for leafy greens​​
Image of a modified washing machine used to spin dry leafy greens.
Project Description: 

Many small-scale farms build green spinners by modifying washing machines to dry produce as an affordable and more accessible alternative to commercial green spin dryers. However, knowing that sanitation is a leading contributor to foodborne outbreaks and recalls, the cleaning of these units is not well understood. As growers are subject to the produce safety regulations and more buyers are requesting voluntary food safety audit programs, there may be compliance challenges from inspectors or auditors unfamiliar with such non-traditional processing equipment. For example, within the FSMA Produce Safety Rule (PSR), specific regulations discuss postharvest handling and sanitation states, postharvest equipment needs to be of “adequate design, construction, and workmanship to enable them to be adequately cleaned and properly maintained” (FSMA PSR § 112.123(a)).  

The question about the use of washing machines for spinning greens is a very common topic of discussion with growers, yet presently, no research has been established to inform growers on developing specific best practices. Recognizing that all farms have limited time and resources, this project investigates the risks of drying leafy greens and compares it to a commercially available greens spinner (an Electrolux “VP2 Greens Machine).  The project aims to manage risks associated with this common practice and provide science-based guidance to make better-informed decisions about best practices on farms.  

Project Goals and Objectives: 

The long-term goal of this project is to identify reasonable, easily applicable approaches for improving cleaning and sanitation practices to reduce the overall incidence of foodborne illness. The short-term goal is to investigate the potential microbial contamination risks of modified washing machines and investigate potential approaches that can help reduce these risks that can then be applied as a sanitation practice to improve food safety management.  

  • Objective 1: Identify, source, and build modified washing machines for drying leafy greens using the resources in building modified washing machines for spin drying leafy greens for small-scale leafy green operations. 
  • Objective 2: Conduct a science-based risk hazard identification assessment to investigate the harborage and sanitation risks of using modified washing machines to dry leafy greens. 
  • Objective 3: Develop and design a mixed-media portfolio of extension-based tools, focusing on the principles of cleaning and sanitation, sanitation design, and sanitation management. 

Relevance: 

The project is focused on managing the risks associated with leafy green spinners. Its goal is to offer guidance grounded in science, enabling farmers to make more informed decisions to improve best practices on their farms. 

Outputs and Extension Materials: 

Publications 

  1. Kamarasu P, McLandsborough L, Moore MD, Kinchla A.J. (peer-reviewed). Evaluating the potential for contamination of leafy greens with Listeria when using retrofitted washing machines. Npj Science of Food (Under Review).  
  2. Kamarasu P, McLandsborough L, Moore MD, Kinchla A. J. (peer-reviewed). Evaluating the influence of different cleaning and sanitation interventions on microbial and ATP recovery in an emerging leafy greens processing apparatus. (In Preparation).  
  3. Harathy Chennupati, P., Kamarasu P, McLandsborough L, Moore MD, Kinchla, A.J. Evaluating the influence of different cleaning and sanitation interventions on microbial and ATP recovery in an emerging leafy greens processing apparatus. (In Preparation).  

Oral Presentations delivered to food safety communicators who work with growers  

  1. Kamarasu, P.  Moore, M.D., Kinchla, A.J. “ The Risk Assessment of the Sanitation Practices of Modified Washing Machines in the Processing of Leafy Greens”. International Association for Food Protection, Annual Meeting. Toronto, July 17, 2023. Session. T4-09. 
  2. Kamarasu, P., Moore, M.D., Kinchla, A.J. Evaluating the Risks Associated with Utilization of Modified Washing Machines in Processing Leafy Greens. International Association for Food Protection, Annual Meeting. Pittsburg, July 31 - August 3, 2022. Session. T8-09. 
  3. Kamarasu P, Moore MD, Kinchla A. Evaluating the Use of ATP Swabs as a Sanitation Indicator When Using Washing Machines to Dry Leafy Greens. Poster. Institute of Food Technologists FIRST 2022 (Annual Meeting). Virtual/Chicago, IL, USA. July 2022.  
  4. Kamarasu P, Moore MD, Kinchla A. Evaluation of ATP and ADP persistence in produce processing environments and comparison to bacterial load. Presentation. Capital Area for Food Protection-Kikkoman Biochemifa Food Safety. Virtual, USA. May 2022.  
  5. Kamarasu P, Moore MD, Kinchla A. Evaluating the risk associated with modified washing machines in processing leafy greens by utilizing ATP Lumitester as an indicator. Capital Area for Food Protection Association Spring Meeting. Virtual, USA. May 25, 2022.  

Poster Presentations 

  1. Kamarasu, P., Moore, M.D., Kinchla, A.J. Evaluating the risks associated with the utilization of modified washing machines in the processing of leafy greens. Poster #2022-06. New England Vegetable, Fruit and Berry Conference. December, 2022. Manchester, NH. 
  2. Kamarasu, K. Moore, M.D., Kinchla, A.J.  Evaluating the Risks Associated with Utilization of Modified Washing Machines in the Processing of Leafy Greens. Northeast Center to Advance Food Safety 2022 (NECAFS). Virtual. January 2022. 
  3. Kamarasu, P., Moore, M.D., Kinchla, A.J. Evaluating the Risks Associated with Utilization of Modified Washing Machines in the Processing of Leafy Greens. American Society of Microbiology (ASM) DC Branch Conference 2021. 
  4. Kamarasu, P., Moore, M.D., Kinchla, A.J. Application Research: Evaluating the risks associated with utilization of modified washing machines in the processing of leafy greens”. Northeast Center to Advance Food Safety. 2021 Annual Conference (NECAFS 2021). 
  5. Chennupati, P.H., Kamarasu, p., Moore, M.D., Kinchla, A.J. Comparison of retrofitted do it yourself (DIY) washing machine with commercial drying unit used for drying local fresh produce. International Association of Food Protection, Annual Meeting. Toronto, July 17, 2023. Session P2-172 
  6. Chennupati, P.H., Kamarasu, p., Moore, M.D., Kinchla, A.J. Comparison of modified washing machines with commercial green spinners used for drying leafy greens. Northeast Center to Advance Food Safety (NECAFS). January 2024 Annual Conference. Portland, ME. 

Media 

  1. Washing Machine Greens Spinners. Product Bites. Michigan On-Farm Produce Safety. September 19, 2023. https://producebites.buzzsprout.com/936625/13424250-washing-machine-greens-spinners 
  2. Is it save to spin-dry leafy greens in a washing machine? UMass Amherst researchers studying common practice at small New England farms https://www.umass.edu/news/article/it-safe-spin-dry-leafy-greens-washing. April 21, 2020.   

Sponsorships: 

This work was supported by Specialty Block Crop Grant (SCBGP FY19) administered through the Massachusetts Department of Agricultural Resources, MA, the Capital Area Food Protection Association, Washington, D.C, Kikkoman Biochemifa Company, Tokyo, Japan, the National Institute of Food and Agriculture, U.S. Department of Agriculture, the Center for Agriculture, Food and the Environment, and the Food Science department at University of Massachusetts Amherst, under project number MAS-00529. The contents are solely the authors' responsibility and do not necessarily represent the USDA's or NIFA's official views. 

Acknowledgments: This research was also done with help from the University of Vermont Agricultural Engineering Extension team.