Intense heat and long days serve as a reminder that we are officially in the heart of Summer, where Indiana consumers rush to grocery stores and farmers markets to purchase fresh, locally-grown fruits and vegetables. As produce farms strive to meet this demand, it is important that growers consider food safety and follow good agricultural practices to protect these consumers from foodborne illness outbreaks. Simple actions such as training workers in food safety, monitoring water quality, and proper handling of waste and soil amendments go a long way in reducing food safety risks on the farm.
Farm workers, including paid and volunteer laborers, form the foundation of a successful produce farm. Most fruit and vegetable operations require manual labor, where workers harvest and pack produce with their hands, which creates the opportunity for contamination with foodborne pathogens. To reduce this risk of contamination, produce farms must train their workers on good food safety practices upon hire and at least once annually in a language that is easily understood by all workers. Training programs must review proper handwashing, personal hygiene, proper use of toilets, how to handle illness and injury, how to identify if someone is sick and other food safety risks at harvest. When delivering this training, growers may utilize videos, such as the Fruit and Vegetable Food Safety Training Video for Field Employees developed by the Produce Safety Alliance.
Figure 1. Workers at the Purdue Student Farm harvesting vegetables (Photo by Tom Campbell).
Another important food safety consideration for produce growers is water quality. Insufficient water quality can result in wide-spread contamination of fruit and vegetable crops during irrigation, application of crop sprays, and other instances where the water directly contacts the produce. Therefore, proper water management is key. With the exception of root crops, produce farms can reduce risk by limiting the contact of water with the edible portion of the crop through utilization of drip or trickle irrigation. Water source can also impact risk. Growers should utilize public or ground (well) water sources over surface water from ponds, streams, and reservoirs when possible. Surface water is open to the environment, making it difficult to control animal access, runoff, and other potential sources of contamination. Finally, produce growers may choose to monitor their water quality by testing their water for generic E. coli. The presence of E. coli indicates that there was fecal contamination of the water source, and there could be an issue with water quality that needs to be addressed. Growers can find a list of laboratories that can test their water on the Safe Produce Indiana website.
Figure 2. Student collecting a surface water sample for microbial testing (Photo by Tom Campbell).
Biological soil amendments of animal origin such as manure, bone meal, and fish emulsion can be indispensable for promoting plant growth and improving soil quality. However, they can carry a biological risk. For growers who choose to apply biological soil amendments of animal origin to their fields, proper handling of these materials is essential to preventing contamination. Growers are encouraged to select soil amendments that have undergone a validated treatment method, such as composting. If a farm chooses to apply raw manure or another untreated soil amendment to their field, this should be applied 90-120 days prior to harvest to maximize the application interval and reduce microbial risk. Growers should never side-dress with raw manure. All biological soil amendments of animal origin should be stored away from produce fields, water sources, and high-traffic areas. Finally, workers who handle soil amendments should receive training on proper handling to prevent cross contamination.
By following these food safety practices, growers can reduce biological risk associated with produce grown on their farm. Food safety can be an overwhelming topic for produce growers to navigate. But never fear; Safe Produce Indiana is here! Purdue Extension’s Safe Produce Indiana team is available to answer produce growers’ questions about food safety and help them navigate produce safety regulations and audit standards. Safe Produce Indiana has also curated several food safety resources for produce growers. Visit safeproducein.com to learn more, or contact a member of our team today!
Dr. Amanda Deering
Associate Professor
Cell: (765) 586-7544
Email: adeering@purdue.edu
Scott Monroe
Food Safety Educator
Cell: (765) 427-9910
Email: jsmonroe@purdue.edu
Tari Gary
Extension Administrator
Phone: (765) 494-8271
Email: tgary@purdue.edu