Food safety related to horticultural commodities is clearly important. Fourteen percent of foodborne disease outbreaks in 2007 were due to leafy vegetables (Centers for Disease Control and Prevention, 2010). Of the 18 multistate Salmonella outbreaks reported for 2007, spinach (Spinacia oleracea) and lettuce (Lactuca sativa) accounted for 76 illnesses, ‘Beefsteak’-type tomatoes (Solanum lycopersicum) for 65 illnesses, and raw fresh basil (Ocimum basilicum) for 11 illnesses. Leafy vegetable salad contaminated with norovirus led to one of the largest number of (128) illnesses associated with a single food commodity.
In response to these outbreaks, in 2010 the U.S. Food and Drug Administration (FDA) announced a proposed rule for the safe production, harvesting, and packing of fresh produce. The ruling is in comment period through 2011, and a final version is anticipated to be published in early 2012. The rule will apply to a heterogeneous industry growing many crops and on various-sized farms. Between 2005 and 2007, the U.S. Department of Agriculture's (USDA) Agricultural Resource Management Survey reported that there were 30,449 specialized vegetable and melon [melon (Cucumis spp.) and watermelon (Citrullus lanatus)] farms, generating ≈14% of all U.S. crop (agronomic and horticultural) cash receipts (Ali and Lucier, 2011). This survey defined a farm as “any place from which $1,000 or more of agricultural products were sold or normally would have been sold annually,” and a specialized vegetable farm is one where “vegetables and melons account for at least half of the total value of farm production.” Very large farms, with a gross income of $1 million or more per year, accounted for 87% of total vegetable crop value and are concentrated in the western United States. Small farms, with less than $40,000 gross farm income a year, made up 67% of all vegetable farms and are concentrated in the southern United States. Nearly 18,000 (26%) of farms growing vegetables and melons sold their product directly to consumers (Lucier et al., 2009), resulting in $335 million in 2007 or ≈19% of all vegetable and melon sales. Direct sales to consumers are increasing, up 69% in 2007 from 2002 and up 97% from 1997. With the increased sales and increased emphasis on “buy local” and farm-to-school programs, paying attention to GAPs and food safety at the local farm level is more important than ever, especially given the July 2011 Escherichia coli outbreak in Oregon on strawberries (Fragaria ×ananassa) sold at local farmers markets (Modie, 2011) and the Listeria outbreak (Centers for Disease Control and Prevention, 2011) linked to Colorado cantaloupes (Cucumis melo).
In 1998, the FDA and USDA jointly published guidelines for avoiding contamination by microbial human pathogens when producing and handling vegetables. These guidelines, titled “Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables,” have been used as the basis for GAPs audits, performed by state agencies and private companies.
Since the publication of these guidelines, various researchers have used mail surveys to understand the degree to which farmers have implemented GAPs on their farms. Rangarajan et al. (2002) surveyed 615 fruit and vegetable growers in New York, receiving 213 responses. With a response rate of 35%, the respondents’ farms represented 25% of all vegetable and 11% of all fruit acreage in New York. Average farm size was 250 acres, but 54% of respondents farmed less than 100 acres. Areas identified for further education included increasing awareness of outbreaks associated with fresh produce, recordkeeping of manure applications, composting processes, irrigation water quality testing, and use of sanitizers in wash water.
Cohen et al. (2005) sent out mail surveys to 609 fruit and vegetable growers in six New England states, obtaining a 49% response rate. Demographic information on the growers was not included, however as with the New York growers, farmers participating in this survey did not test irrigation water or use sanitizers in wash water, and could improve record keeping. Growers also infrequently cleaned harvest containers before use or sanitized storage containers and packing equipment. Most used water without sanitizers for cleaning food processing surfaces and bare hands for packing produce. Ellis et al. (2005) interviewed nine Iowa growers of produce operations ranging in size from 1.5 to 80 acres and found that growers could improve handwashing facilities and practices, cleaning and sanitizing protocols for produce and food contact surfaces, and employee training.
After publication of the FDA and USDA “Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables,” a team of researchers at the University of Minnesota started food safety awareness education at grower conferences in Minnesota. Other educational events were held, including GAPs and food safety plan writing workshops, education and technical assistance was provided to growers, and demonstration GAPs audits were hosted for growers. To learn which areas should be emphasized in future GAPs educational efforts, vegetable growers farming in Minnesota in 2008 were surveyed by mail.
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