By Sharon Motomura
By Sharon Motomura
Junior Extension Agent for Edible Crops
University of Hawaii at Manoa
College of Tropical Agriculture and Human Resources
Komohana Research and Extension Center, Hilo
Summer is officially here, and that means more daylight hours to spend in the garden and a bountiful harvest as a great reward for your hard work.
As you are aware, the garden is a dynamic environment in which you can control only certain aspects. One aspect that you can control, is the level of contamination by agents of food-borne illnesses on your garden produce.
That being said, here are a few suggestions to make sure everyone stays healthy by eating fresh fruits and vegetables from the garden, and by greatly reducing the possibility of illness.
The first step you can take is to locate your garden away from sources of manure. These sources can be dog kennel, pasture, or poultry house — and especially if they are located upslope from your garden.
Remember the saying about things flowing downhill! Keeping your pets and livestock out of the garden will reduce the risk of foodborne illness. Animal manures can contain salmonella or E-coli, both which can cause illness and even death. Wild pigs in a vegetable production field were implicated in a large food-borne illness outbreak a few years back that included many deaths.
If your garden is flooded, do not eat crops that have had the edible portion exposed to flood waters as they can become contaminated with pesticides, feces, slugs, snail, and other pests. When harvesting produce, start with clean hands, wash your hands and wrists for at least 20 seconds with soap and warm water and dry them with a clean paper towel.
Also be sure that you clean your harvest tools and avoid laying them on the ground. Placing harvested produce and tools on bare ground can contaminate them with illness causing agents. Inspect your plant produce before harvesting for signs of badly damaged (something eating) or contaminated with bird droppings or feces.
Place harvested produce in clean harvesting bucket or wheelbarrow and it is also a good practice to line your wheelbarrow with clean paper or cardboard. One large food-borne illness outbreak in the U.S. was caused by hauling produce on a truck that was previously used to haul animals.
I have received questions about the best way to wash fruits and vegetables to reduce pathogens and to remove conventional or organic pesticide residues.
Perhaps you have seen commercial fruit and vegetable washes.
A recent scientific study done by the University of Maine on blueberries compared distilled water with three different commercial washes. The distilled water was just as effective as, or better than, the commercial washes in reducing the amount of microbes or pathogens and pesticide residues. Distilled water is filtered and purified, similar to the bottled water we drink and is likely free of contaminants, making it a good “control” for the study.
If you don’t have distilled water, Hawaii County-provided tap water will do nicely.
It is important to use potable (drinkable) water when washing produce, as streams, ponds, and catchment water systems without proper treatment may introduce illness-causing agents. This is because these sources can be contaminated with animal pathogens (from fecal matter) or other illness-causing agents. Thus, you might be taking perfectly safe produce and making it less safe by washing with untreated water.
Once in the kitchen, precautions do not end; be sure to clean all surfaces, cutting boards, and utensils with soap and hot water. It is important to rinse all produce even if you are not eating the skin or rind because microbes on the outside can make their way inside when it is cut or peeled.
Avoid using dishwashing detergent to clean produce because the residues can cause diarrhea if not rinsed off completely. Again, potable water works best. For produce with firm skins like avocados, potatoes or oranges you can rub them with clean hands or scrub with a vegetable brush under running cold tap water. For complex produce like lychee, broccoli and cauliflower you can presoak them in cold, potable water for two minutes prior to thorough rinsing. Delicate leafy vegetables can be soaked then rinsed with clean water. For produce like leaf lettuce, be sure to carefully wash where the leaves connect to the stem as dirt can collect in this area. Separating the leaves from the stem will result in better cleaning.
For delicate fruits such as guava, strawberries, or cherries you can place them in a colander and rinse under cool running, potable water just before serving them. Dry produce with a clean towel or use a produce spinner as this may also help reduce moisture that supports the growth of microbes. Once you are done washing and cleaning your produce items, store them correctly whether itís dry cool or refrigerated and keep from being contaminated with illness causing agents.
To download a free CTAHR publication on Best Food Safety Practices for Hawaii Gardeners, visit: http://www.ctahr.hawaii.edu/oc/freepubs/pdf/FST-41.pdf.
For more information on food safety and other gardening topics, please visit the CTAHR electronic publication website at http://www.ctahr.hawaii.edu/Site/Info.aspx or visit any of the local Cooperative Extension Service offices around the island.
Sharon Motomura can be reached at smotomur@hawaii.edu.