Preventing foodborne illness at your farmstand

Whether in field or farmstand, farmers’ market or farm store, the safety of food has become everyone’s business.

Whether in field or farmstand, farmers’ market or farm store, the safety of food has become everyone’s business.

Publicity surrounding E. coli in spinach, listeria in dairy products, salmonella in eggs and chickens, and other pathogens in foods has raised general awareness of issues surrounding foodborne illnesses and safe food. As a result, consumers have joined the more than 3,000 municipal, state, federal and tribal agencies in overseeing safe growing, harvesting, transporting and sale of food. “Your customers are watching!” says Alice Mullen, extension educator, University of New Hampshire.

In 2011, the Centers for Disease Control and Prevention (CDC) estimated that every year one out of six Americans (48 million people) get sick and 3,000 people die of foodborne illnesses. While many foodborne illnesses were traced to large farms, contamination can occur anywhere.

What causes foodborne illnesses?

While it is being grown, harvested, distributed and prepared, food may become contaminated with disease-causing pathogens. Irrigation or washing water contaminated with animal manure or human sewage can contaminate produce. Animals (even healthy ones) raised for food may carry pathogens, usually in their intestines. Bacteria or other pathogens in food usually enter the body through the gastrointestinal tract, causing the first symptoms of foodborne illness there. Nausea, vomiting, abdominal cramps and diarrhea are common symptoms. Bacteria (campylobacter, salmonella, and E. coli O157:H7) and a group of viruses (called calicivirus, also known as Norwalk viruses) cause the most commonly recognized foodborne illnesses. Because bacteria generally need time to multiply, symptoms of bacterial infections are generally not seen until 12 to 72 hours or more after contaminated food is eaten.

No matter what the type of pathogen, some people – very young children, pregnant women, the elderly and people with compromised immune systems – are at higher risk than others. Regardless of their age or physical condition, some people become ill after ingesting only a few harmful pathogens. Others remain symptom-free after ingesting thousands.

The big yucks

Foods most likely to become contaminated with viruses, parasites, fungi or bacteria are high-protein and/or low-acid foods. Bacteria are the greatest threats to food safety. They grow best in temperatures ranging from 41 to 140 degrees Fahrenheit in moist, protein-rich conditions that are pH-neutral or low-acid. Given warm, moist conditions and sufficient nutrients, a single bacterium that reproduces by dividing itself every half hour can produce almost 17 million progeny in 12 hours. Thus, lightly contaminated food left out overnight can be quite infected by the following day.

Among the most potentially hazardous foods are chicken, eggs, milk and meat, as well as strawberries, raspberries, sprouts, green onions, lettuce and leafy greens. Unpasteurized juice is also potentially hazardous, as are sliced melons and tomatoes, often offered as samples. Bacteria on the surface of melons and tomatoes (especially melons since they grow on the ground) can be transferred from the exterior of the fruit to the interior by the slicing knife.

Even safely cooked, ready-to-eat foods can become contaminated. Bacteria can be transferred from raw produce, from meat juices, or from anyone who has handled them, especially people with poor personal hygiene.

The factors most frequently contributing to an outbreak of foodborne illness:

  • Food from an unsafe source. Unsafe sources may include places where good agricultural practices (GAPs – usually preharvest) and good handling practices (producers and packers) are not observed.
  • Inadequate cooling and improper holding temperature.
  • Unclean or improperly cleaned and sanitized equipment.
  • Poor personal hygiene.
  • Cross-contamination. Harmful substances on raw agricultural products can be transferred from one surface to another. Infected humans who handle food or who use the same knife, cutting board or other utensil can also transfer disease-causing pathogens.

Hold that temp

By far, the biggest factor contributing to unsafe food is improper holding temperature. Hot foods must be kept hot, cold foods cold. Hot food should be maintained at 140 degrees Fahrenheit or above. Cold food should be kept refrigerated at 40 degrees Fahrenheit or below. Frozen food should be kept frozen.

Although refrigeration or freezing generally prevent bacteria from multiplying, they do preserve bacteria in a state of suspended animation. However, two foodborne bacteria, Listeria monocytogenes and Yersinia enterocolitica, can grow at refrigerator temperatures. Before widespread use of refrigeration, preserved foods had to have high salt, high sugar or high acid levels to keep bacteria from growing. This is why traditional preserved foods tended to be salted meats, jams and pickled vegetables.

Where permanent refrigeration is not available, such as at farmers’ markets or stands, cold foods may be maintained in coolers packed with ice, dry ice or blue ice packs. A refrigerator thermometer should be kept in the cooler and checked frequently to be sure the temperature is kept at 40 degrees Fahrenheit or cooler.

The gloved hand

To prevent the spread of pathogens causing foodborne illnesses, all food handlers should wash hands frequently. To be effective, hands should be washed for 20 seconds in warm water and soap, rinsed and dried with a single-use paper towel. It is a good practice, and required by many regulating agencies, that gloves be worn by everyone who handles ready-to-eat foods. Ready-to-eat foods are not only those served in restaurants, but also value-added products (such as baked goods and soups), as well as samples available at farm markets and stores. Gloves should be put on newly washed hands and should be changed between tasks or at least every four hours when working on the same task, or if they become soiled or torn.

Who regulates food?

Overseeing the safe handling of food is the responsibility of multiple local, state and federal entities. Discovering which regulators and regulations apply to each situation can be challenging. Colleen Smith of the New Hampshire Department of Health and Human Services, Food Protection, advises starting with your county extension agent. Your extension agent can point you to the governmental units responsible for overseeing the safety of various foods in your markets. In New Hampshire, for instance, the New Hampshire Department of Agriculture oversees raw vegetables, meat, maple syrup, honey and pet food. Each state, as well as the federal government, may have different and/or multiple agencies involved in regulating various products. Products crossing state lines are, in general, subject to federal oversight. Value-added products such as jams and baked goods must, in general, be prepared in a commercial, inspected kitchen. Again, state and local regulations vary.

For a comprehensive set of regulations, consult the Food and Drug Administration’s (FDA) model code. This lengthy, but searchable, document, written primarily for grocery stores and restaurants, is available at

A matter of trust

Controlling the risk of foodborne illness is, of course, essential to protecting your family business, as is knowledge of and compliance with applicable regulations. However, beyond compliance is perception. Your customers trust that the food you bring to market is safe. As Stuart Farnham, a certified farm insurance specialist with Nationwide Insurance, points out, “One bad egg and everyone – you and other farmers – looks bad.”

He advises creating a culture of awareness of food safety. Practices your customers will quickly notice are hand washing stations and signs advising them what to do and how to avoid hazards.

Safe food is a practical way to increase the value of your agricultural products. Your reputation for good, safe food may also increase marketability and enlarge distribution opportunities.

In sum

  • Customers trust that your product is safe.
  • Practice good personal hygiene.
  • Prevent cross-contamination by careful cleaning and sanitizing.
  • Keep cold foods cold, hot foods hot.
  • Your customers are watching.

Kathleen Hatt is a freelance writer and editor and a frequent contributor to Growing. She lives in Henniker, N.H.