Take Safety on Your Picnic
Jeannie M. Leonard
Family and Consumer Science Extension Agent
Picnic foods can be hazardous for several reasons. Food receives a lot of handling. Picnic foods—such as potato or macaroni salads, sandwich fillings, hamburger patties, and cut watermelon—often receive a lot of handling during preparation. Handling increases the risk of contamination with harmful bacteria.
Food is not cooled rapidly after cooling is another hazard. Some common picnic foods require precooking and are prepared in large quantities. Cooked foods must be rapidly cooled by putting in shallow pans and refrigerating immediately after cooking so harmful bacteria does not grow. Warm temperatures promote bacterial growth.
Another hazard is that equipment to keep hot food hot and cold food cold is usually not used and food sits out for long periods of time. Warm temperatures support the growth of harmful bacteria. The longer food is at warm temperatures, the more likely food borne illness will result.
The following guidelines will help keep your picnic food safe:
- Wash hands before handling food and use clean utensils and containers. Dirty hands, utensils, containers and any work surfaces can contaminate food with harmful bacteria and viruses.
- Do not prepare foods more than one day before your picnic unless it is to be frozen. Cooking foods in advance allows for more opportunities for bacteria to grow. Cooked foods need to be rapidly cooled in shallow pans. Spread the food out in as many pans as is needed so that food is no more than two inches deep. Over 67% of reported cases of food borne illnesses are due to improper cooling. Frozen foods can be used if thawed in the refrigerator.
- Mayonnaise-based foods need to be kept cold. Mayonnaise alone is too acidic for bacteria to grow in it. However, when mayonnaise is mixed with other foods, (particularly those that have been handled a lot and/or are protein foods), bacteria can grow if this mixture is kept too warm.
- Cut melons need to be kept cold. Many people do not realize that melons, such as watermelon and cantaloupe, can cause food borne illness. Bacteria, such as Salmonella and Shigella (common causes of food borne illness), are often present on the rind. Therefore, be sure to wash melons thoroughly before cutting, then promptly refrigerate cut pieces. Melons, unlike most other fruits, are not acidic and so can support the growth of harmful bacteria.
- Keep cold food cold. You need to keep cold food at 40 degrees F. or colder to prevent bacterial growth. To do so, pack cold foods in a sturdy, insulated cooler with plenty of ice or frozen gel packs. Freeze your own blocks of ice in milk cartons or plastic containers for use in the cooler. Put cold foods in water-proof containers or wrap in plastic wrap or aluminum foil and completely immerse in the ice inside the cooler. If using frozen gel packs or containers of homemade ice, place them between packages of food. Keep the cooler closed until ready to use the contents.
- The trunk of your car can reach temperatures of 150 degrees F., so it is best to transport coolers in the passenger area of the car. When you arrive at the picnic site, put a blanket over the cooler and place it in the shade to maintain cold temperatures. Keep the cooler closed until ready to use the contents.
- Keep hot food hot. You should keep hot foods at 140 degrees F. or hotter to prevent the growth of harmful bacteria. Takeout foods or foods cooked just before being transported to the picnic can be carried hot. Wrap hot food in towels, then in newspaper, and place inside a box or heavy paper bag. Keep these foods warm on a lit grill or use within one hour.
- If you cannot keep cold food cold and hot food hot, take foods that do not need refrigeration. For example, peanut butter sandwiches, dried fruit, nuts, unpeeled fresh fruit (apples, oranges, bananas), jelly sandwiches, unopened cans of food (meat, fish, or fruit), cookies, cakes, and crackers are all good choices.
- Wash your hands. Pack moist towelettes if you think your picnic site might not have hand washing facilities available. Hands carry harmful bacteria and viruses that contaminate food and cause illness.
- Pack plenty of utensils and dishware. Never use the utensils and dishware that have touched by raw foods, such as meat, fish and poultry, to store fresh or cooked foods unless they have been washed between uses. Juices from some raw foods contain harmful bacteria that can contaminate other foods and cause food borne illness. Because proper washing might be difficult at a picnic, pack extra plates and utensils to prevent cross-contamination. Better yet, consider using disposable plates.
- Whether you are cooking indoors or outside on a grill, meat and poultry must be cooked thoroughly to ensure that harmful bacteria are destroyed. Grill raw poultry until the juices run clear and there is no pink close to the bone. Hamburgers should not be pink in the center.
- Prevent contamination of food by insects by keeping the foods covered. Many insects can carry harmful bacteria and viruses on their bodies.
- At the end of the picnic, you should throw away leftovers, because most of them have been sitting out for more than one hour and have had many people handling them. The more time that food has been sitting at unsafe temperatures, the more likely harmful bacteria has grown.
- Cold foods kept in a cooler that still has ice may be safe. If the ice is melted, throw out the food. Cold water cannot keep foods cold enough to be safe.