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Impact of Employee Training on Mitigating Contamination in Retail Foodservice Operations

Threats to the safety of the food through direct contamination or cross contamination can be presented at any point as food flows through a retail foodservice operation. Cross contamination is defined as the “transfer of harmful substances or disease-causing microorganisms from one food product to another through direct contact, or contact with utensils, equipment, or work surfaces, or employees’ hands or clothing” (National Restaurant Association Educational Foundation [NRAEF], 1999, p G-12).

This project has used in-depth field observations and microbiological analyses to determine practices relative to contamination in various types of retail foodservice operations, quantify the impact of pathogens on food as it flows through the establishment, and develop effective employee training strategies to mitigate contamination.  This project builds upon previous research in retail foodservice operations, particularly examining employees’ role in contamination and testing strategies to improve employee food handling. The project is funded through the USDA Cooperative State Research, Education and Extension Services (Project No. 2005-51110-03282) began September 2005 and will conclude August 2008.

Project Team
Catherine Strohbehn, PhD, RD, CFSP
HRIM Extension Specialist

Sam Beattie, PhD
Consumer Food Safety Specialist

Jeannie Sneed, PhD, RD, SNS, CFSP
former ISU Professor

Janell Meyer, MBA
Project Coordinator

Paola Paez, MS
Foodservice and Lodging Management doctoral student


Project Goal and Objectives
The goal of the project is to identify and implement employee training strategies to mitigate contamination in selected retail foodservice operations (day care centers, schools, assisted-living facilities, and restaurants) based on observed employee hygiene and food handling practices, and microbiological data. Specific objectives are to: 

  1. Determine current and desired handwashing frequency of employees in retail foodservice establishments.
  2. Determine steps in the flow of food where contamination is most likely to occur.
  3. Evaluate employee food handling practices that contribute to contamination.
  4. Evaluate ready-to-eat food products and fresh leafy produce throughout the food flow to determine the extent of bacterial contamination.
  5. Evaluate food contact surfaces to determine the extent of bacterial contamination.
  6. Assess current food security (a potential source of intentional contamination) in retail foodservice establishments.
  7. Develop and test employee training strategies to mitigate contamination in retail foodservice operations.


Study Sample. Four day care centers, schools, assisted-living facilities, and restaurants (a total of 16 operations) in central Iowa were selected for the study.  Day care centers, schools, and assisted-living facilities were selected because they serve populations vulnerable to foodborne illness. In addition, foodservice workers often have additional duties within the organization that may present an opportunity for contamination to occur, such as day care workers who change diapers or universal care workers in assisted living facilities who provide personal assistance.  Restaurants were selected because a high proportion of foodborne illness outbreaks are attributed to restaurants, because vulnerable populations eat in restaurants, and because there are significant issues related to food handlers (i.e. high turnover, little training, limited English skills).  Participating facilities have some on-site food production, serve at least two meals or snacks each day, and serve unprocessed fresh leafy produce (such as lettuce or celery) and ready-to-eat processed deli meats. These food items do not receive heat treatment before service and will involve some handling by employees.

Overall Project Design. This project consists of two phases. The first phase involved five on-site visits to each participating facility (80 visits) in the first year to analyze handwashing methods and frequencies and food preparation practices. Based on observations, a model of desired handwashing frequency was developed. The Handwashing Observation Form developed by Paez, Strohbehn and Sneed, is a validated data collection instrument.

The second phase of the project consists of a pre-test/post-test research design.  Four additional site visits will be made to each of the 16 research sites (64 total visits).  A summary of Phase II activities at each site visit includes:

  • Site Visit 1  (Year 1)
    • Observe employee food handling practices
    • Assess current food security practices
    • Collect food and swab samples
    • Install digitized hand soap dispenser
  • Site Visit 2  (Year 1)
    • Observe employee food handling practices
    • Collect food and swab samples
    • Conduct handwashing training session
    • Install DigiGlo Box
  • Site Visit 3 (Year 2)
    • Conduct training related to contamination
    • Conduct training related to food security
  • Site Visit 4 (Year 3)
    • Observe employee food handling practices
    • Assess food security practices
    • Collect food and swab samples

Based on observations and results of microbiological analyses collected in year one, employee training strategies for mitigating contamination improving food security were developed. Strategies included introducing written policies and procedures, modifying current procedures, providing training and training materials, recommending equipment changes, and others. The project methodology and data collection instruments were approved by the Iowa State University Institutional Review Board prior to data collection.


Contamination and Cross Contamination of Foods
Foods can become contaminated at many points from origin to service, or at any link in the food chain. Contamination can be inadvertent, or it can be an intentional effort to sabotage the food, thus resulting in a wide spread outbreak of foodborne illness. The Farm-to-Fork Concept is a useful way to identify various links of the food chain and implement procedures to minimize risk from hazards occurring at each step.

The majority of reported foodborne illnesses have been linked to foods prepared in retail foodservice operations, including restaurants, childcare centers, schools, and assisted-living facilities. Each foodservice operation has pathways food follows once it arrives at the establishment. The typical flow for conventional foodservice establishments is purchasing, receiving, storage, production (thawing, preparation, cooking, holding), service, cooling, and reheating.  Some facilities also transport food after preparation to other sites where it is served.

Retail foodservice operations are required to purchase potentially hazardous food (PHF) from approved suppliers. These foods are inspected at the federal or state level and approved safe for human consumption. Controls to prevent time-temperature abuse and other contamination during distribution are less stringent, due to the transitory nature of the process.

Currently, Hazard Analysis and Critical Control Point (HACCP) systems are required for meat, poultry, seafood, and juice processing facilities.  These systems are not required for retail foodservice operations such as restaurants, childcare and assisted-living facilities in Iowa and most other states, although recent legislation (Child Nutrition and WIC Reauthorization Act of 2004) did require school meal programs participating in the USDA program to begin implementation of a food safety program based on the process approach to HACCP by July 2006.