Author: Sam Angima
Publish Date: Spring 2008
Food-borne illness outbreaks have made numerous headlines in the past two years and the Center for Disease Control and Prevention (CDC), estimates that every year, 76 million cases of food-borne illness and 5,000 associated deaths occur in the United States. For example, in the fall of 2006, over 199 people became ill and 3 died as a result of eating E-coli contaminated spinach. While this was traced to specific large farms, it is imperative to understand how contamination can occur in any farm. As the vegetable and fruit growing season progresses, producers need to be up-to-date on practical steps that can be taken to lessen the instances of food-borne illness originating on the farm.
To prevent the spread of pathogens that cause foodborne illness, it is important to understand what those pathogens are and how they survive. A number of foodborne pathogens are present in the intestinal system of healthy animals. Foods can become contaminated or cross-contaminated if they come into contact with even a small amount of pathogen-contaminated intestinal contents. These pathogens are then capable of surviving without an animal host sometimes up to a year in manure slurry and contaminated soils, while others can survive on fruits and vegetables.
Site Selection & Irrigation Water
Food safety must first begin on-farm with site selection of land. Soils that have had previous microbial contamination should be tested for current microbial persistence and soil fertility. While manure may be a valuable and cheap nutrient to increase soil fertility, it can also increase the risk of E-coli, Salmonella, and Campylobacter and other pathogens contributing to microbial contamination. To reduce this risk, manure should be aged, composted prior to being put onto food crop producing fields and should be incorporated into the soils prior to planting food crops. Safe application of manure to food crop soils range from 90 to 120 days prior to harvesting of crops. Food producing acres should ideally be upwind and upstream from animal wastes, contaminated water, and other contaminants. Irrigation water, also a potential medium through which food-borne illness may be spread through direct contact with a food crop (such as water directly hitting the fruit), may enter the plant or food through a puncture in its skin. It may also be spread through the root system of the plant. To limit the spread of foodborne illness through irrigation waters, use only potable or drinkable water. Having irrigation water sources tested for contaminants may assist a producer in identifying pathogen risks associated with their irrigation water or its source.
Field Management & Handling
Field management is very important in decreasing the spread of food-borne pathogens. Staying out of wet fields will reduce the risk of cross-contamination that can be spread through the soils. Removing field soil from products and their harvesting bins prior to moving them into packing areas, as well as avoiding harvesting of fruits and vegetables that have dropped to the ground, are good methods to adopt. Attempting to keep all animals, including pets and wild animals out of food crop fields and packing areas is a reasonable step that will decrease the risk of cross-contamination. Keeping farm machinery and harvesting tools clean and stored to avoid potential crosscontamination is also another measure to reduce risk. Wash, rinse and sanitize harvesting, storage and transportation bins and store harvested products at the proper temperatures to avoid potential contamination or cross-contamination. Instilling proper hygiene methods, including using soap and warm water for workers to use, should be developed for your farm and anyone tending or harvesting your food crops. Institute hand-washing prior to entering the field, as well as exiting fields. Maintain clean hand-washing stations, restroom facilities, packing facilities and modes of transportation and avoid working in field or in direct contact with crops if you are ill. Following pesticide label directions is a must for every producer, whether organic or conventional.
[Food handling information credit: Crystal Weber, University of Missouri Extension]
Farm Internship Curriculum from Western Sustainable Agriculture Research & Education (SARE)
ATTRA - the National Sustainable Agriculture Information Service - is making available a free, online version of a Western SARE curriculum for interns designed to be used by individual farmers during the course of the workweek. Ideally, a farmer will use the In-Field Curriculum when he or she is demonstrating a new task to interns. A companion handbook was authored by Maud Powell (an OSU Extension Small Farms faculty member) and developed and tested by Oregon farmers and interns. It details successful methods of recruitment, hiring, negotiating with, training, and managing interns. The curriculum and handbook are available at: http://attra.ncat.org/intern_handbook/
New from ATTRA: Ruminant Nutrition for Graziers
Cattle, sheep and goats have the ability to convert plant carbohydrates and proteins into available nutrients for human use, making otherwise unusable land productive. However, proper care of the land and its grazing animals requires a sound understanding of ruminant nutrition. This 2008 ATTRA publication provides managers with tools and references to consider biological and climatological variables and make decisions that ensure the ecological and economic viability of a grass-based ruminant livestock operation. The publication is available online at: http://attra.ncat.org/attra pub/PDF/ruminant.pdf
AGA Announces Grass-Fed Standard
The American Grassfed Association (AGA) announced February 20 that its board has voted to start certifying grass-fed meat operations under a new industry-backed standard administered by Food Alliance, according to Sustainable Food News. AGA’s grass-fed marketing claim standard exceeds the requirements for USDA’s grass-fed standard, and specifies a total forage diet, no confinement, no antibiotics and no added hormones. The story notes that Food Alliance may start inspections under the new grass-fed standard by May. For more information go to http://www.americangrassfed.org/