While the United States enjoys one of the safest food supplies in the world, the Centers for Disease Control estimates that 1 in 6 people gets sick from a foodborne illness each year, with fresh produce, including fresh and frozen berries, accounting for nearly half of these illnesses. The key focus areas on farms in considering the risks for microbial contamination of fresh produce are: worker training and health & hygiene, water quality, manure and compost management, domesticated and wild animals, and equipment, tools & buildings. In New England, some buyers are requesting and, in some cases, requiring that growers become certified by a 3rd-party audit program to demonstrate that they are following good agricultural practices, or GAPs, including the USDA’s GAP and Harmonized GAP audit programs. In 2011, the Food & Drug Administration passed the Food Safety Modernization Act (FSMA), which focuses on preventing rather than responding to contamination within the food supply. It consists of seven rules, including the Produce Safety rule, which sets standards for the growing, harvesting, packing, and holding of produce for human consumption. The Produce Rule is the one of the seven that is most likely to impact fruit and vegetable growers. It became effective in January 2016; affected growers will need to be compliant with the rule between 2018 and 2020, depending on their annual gross income. FSMA’s Produce Rule will be enforced at the state level, and each of the six New England states will have their own enforcement models, with either the states Department of Agriculture or Department of Health having statutory authority over the rule.
Following good agricultural practices (GAPs) is necessary to prevent microbial contamination of fresh produce, and to assure continued consumer confidence in fresh, local food. The following is adapted from the Cornell University pamphlet called Food Safety Begins on the Farm. These are some of the steps that farmers can and should take to minimize pathogen contamination during the production and harvest of fresh produce. Be aware that FSMA’s Produce Rule sets specific requirements for covered farms with respect to water quality and testing, worker training, and other aspects of produce production and handling. Refer to the FDA’s Final Rule on Produce Safety, and the resources listed below for more information.
Select Your Produce Fields Carefully. Review the land history for prior use and possible applications of sludge or animal manure. Choose fields that are upstream from animal housings. Know what the upstream uses of surface water are, and test water quality as needed (for coliform bacteria in particular). Prevent runoff or drift from animal operations from entering produce fields by using sufficient separation, adequate buffer plantings, or other means.
Use Manure Properly. In the fall, if applying manure to land in food production, do so preferably when soils are warm (over 50º F), non-saturated, and cover cropped. In spring, incorporate manure at least two weeks prior to planting. Whenever possible, incorporate manure. Do NOT harvest produce within 120 days after fresh manure application (currently FSMA’s Produce Rule does not include an application to harvest interval for raw manure, pending research and a risk assessment. Until that interval is released, it is advisable to follow the 120 day period). Keep records of all manure and fertilizer application rates, source, and dates. Avoid root / leafy crops if manure is applied in spring. Instead, plant field crops like small grains or perennial forages where manure is applied in spring.
Absolutely do not side-dress food crops with fresh solid manure or slurry manure or manure 'tea' or any mulches containing fresh manure. However, it is OK to side-dress with mature composts or compost teas. A mature compost is one that has been thoroughly heated, turned several times, and allowed to age for a long enough time that it is virtually odor-free and is not objectionable to handle with bare hands.
Exclude Animals. NO grazing of livestock should be permitted near produce fields. Minimize wild and domestic animal traffic in produce fields by use of fences, scare devices or other means.
Assure Irrigation Water Quality. Municipal drinking water is low risk. Potable well water is minimal risk if the well casing is maintained and livestock are excluded from the active recharge area. Surface water is higher risk and warrants more intensive testing. Test surface water quarterly or at regular intervals during the growing season (beginning, mid or high draw, and at harvest)—note that FSMA’s Produce Rule requires greater testing frequency and specific testing methods for well and surface waters. Be especially sure to test your irrigation water if the source passes near livestock or sewage treatment. Maintain records of your water tests. Filter or use settling ponds to improve water quality if needed. Use potable water for crop protection sprays. Where feasible, use drip irrigation to reduce crop wetting and minimize risk. If applying overhead irrigation, try to do so early in the day so that leaves dry quickly.
Maintain Cleanliness During Harvest. Check that all harvest containers are clean and in good repair. High-pressure wash and sanitize harvest bins prior to the harvest season and clean bins daily during harvest. Remove excess soil from bins in field. Ensure that packing containers are not overfilled and protect produce adequately from bruising and damage. Avoid standing in the bins during harvest to reduce pathogen spread by shoes. Minimize bruising of produce during harvest. Remove excess soil from produce in the field.
Promote Worker Hygiene. Teach all your workers about microbial risks and the importance of good hygiene. Provide and maintain clean restrooms in or near the field and in food handling areas. Supply soap, clean water and single-use towels for hand washing and enforce their use.
Promote Cleanliness at U-Pick. Invite customers to wash their hands prior to entering your fields. Provide clean and convenient restrooms. Supply soap, clean water, and single-use towels and encourage their use.
Keep Produce Cool. Cool produce quickly to minimize growth of potential pathogens. Use ice made from potable water. Store produce at appropriate temperatures to maintain good quality. Do not overload coolers.
Post-Harvest Handling. Use potable water for all produce washes. Maintain clean water in dump tanks by sanitizing and changing water regularly. Avoid tank water temperatures that are more than 10°F cooler than the temperature of the produce you are washing (so the produce will not absorb wash water into its tissue). Clean and sanitize loading, staging, and all food contact surfaces at end of each day, or more frequently if necessary. Take the steps necessary to exclude all animals, especially rodents and birds from the packing house. No smoking or eating should be allowed in the packing area.
Transportation and Refrigeration. Check and clean out trucks prior to loading them. Sanitize the truck if animals were previously hauled. Pre-cool vehicles prior to loading. Ensure that refrigeration equipment is working properly.
- UMass Extension Food Safety for Farmers - https://ag.umass.edu/resources/food-safety/food-safety-for-farmers
- Produce Safety Alliance at Cornell University - https://producesafetyalliance.cornell.edu/
- A practical GAPs self-assessment for farms, with worksheets that can be printed out from Cornell University's GAP Program - gaps.cornell.edu/educational-materials
- A very detailed self-audit for growers available from University of California Cooperative Extension. - sfp.ucdavis.edu/food_safety/
- The 'Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables' from University of California Division of Agriculture and Natural Resources - ucanr.edu/datastoreFiles/234-204.pdf