Leopold Center for Sustainable Agriculture

Hands-on experience, on-line tools give growers new perspective on postharvest handling

Back to Leopold Letter Winter 2009

By MALCOLM ROBERTSON, Leopold Center program coordinator

EDITOR’S NOTE: This was first published on the Rodale Institute’s New Farm web site. Malcolm Robertson co-leads the Fruit and Vegetable Working Group with ISU Extension Value Added Agriculture specialist Margaret Smith. His background is in applied economics and he is a native of Zimbabwe, where he worked in production horticulture for export. Visit http://www.rodaleinstitute.org/new_farm.

For an increasing number of farmers who are growing fruit and vegetables for direct and wholesale markets, good postharvest handling offers competitive edge, additional profits and fewer food safety concerns.

The Value Chain Partnerships’ Iowa Fruit and Vegetable Working Group conducted two July 2009 workshops that highlighted postharvest handling of vegetables, wholesale sales and preparing produce for market. The sessions were held at Rock Spring Farm in northeast Iowa and Black’s Heritage Farms in central Iowa. These workshops provided an opportunity for participants to see first-hand the steps of harvesting, washing, grading, sorting and packaging as well as a chance to work on the processing line with several types of vegetables at one of the farms.

Presentations focused on the flow of postharvest handling operations and grading standards, also packing, labeling and tracking methods for fresh vegetables. Iowa State University Extension food safety specialist Sam Beattie provided guidance on food safety issues.

Developing a packing facility need not be complicated, but some basic considerations should be taken into account. Some of the key issues discussed at both workshops include start up costs and time commitment, handling systems, hygiene and food safety, and traceability.

Start-up and time commitment

Initial costs for a postharvest handling facility can be as modest as a few hundred dollars for an open-air, outside facility. Proposed food safety regulations likely will change the way that vegetable operations manage their postharvest operations, and may include additional investment to upgrade facilities.

At both farms hosting the workshops, the postharvest handling facilities have changed to accommodate growth within each operation. That growth also has enabled them to offer a better quality product. Chris Blanchard of Rock Spring Farm said new growers should not expect to enter the market with the same type of facilities that he has now. He said it takes experience, time and investment. He recently invested $150,000 to $200,000 in a new vegetable packing facility; when he started his business in 1999, he did all postharvest processing in a small high-tunnel structure. postharvest Chris Blanchard at his Rock Spring Farm near Decorah.

Both growers said that time commitment to their operation was essential, however, that commitment can be small to very large depending on the scale of the operation and number of employees.

Each crop could have different handling systems that may require a different process or equipment to handle all aspects of postharvest.

Design for the next decade

When investing in a packing facility, Blanchard said that growers need to envision where they want to be in 10 years and take into account their harvest-wash-pack system, labor requirements and market potential. The packing shed design then can be more accurately configured to handle produce flow and labor requirements.

At Black’s Heritage Farms, Norine Black told workshop participants that they need to be thinking continually about their washing and packing system to improve efficiency, quality and food safety.

A key element in the handling system is the time it takes produce to move through the operation. This starts in the field at harvest where, for example, some produce may require bunching or topping, tasks you do not want to perform again in the packing shed if the work was done improperly in the field. Blanchard stressed that because labor is a major expense, you do not want to repeat a task.

Once produce moves into the packing shed, having a good system in place ensures an efficient use of time, space and labor. Finally, the speed and capacity of an operation depends on individual workers but can be streamlined somewhat by mechanization.

Clean starts in field postharvest

Food safety practices for fresh produce begin in the field and carry through into postharvest handling. Both growers told participants that the most fundamental aspect to food safety is laborer hygiene, and more specifically, frequent hand washing.

“Hand-washing stations need to be conveniently placed throughout the harvest-wash-pack system,” Blanchard said, “and it would help if these systems were comfortable, such as having hot water for cold days so employees more readily conform to these requirements.”

Another basic requirement for the packing shed is that equipment, tools and surfaces are routinely cleaned and disinfected.

Tracing is critical

The ability to trace products through the system will become more important and may be required in the near future, participants were told. Both Blanchard and Black use a tracking system with a code that is placed on the produce. Blanchard said his system allows him to track a batch of produce back to a field. Beattie explained that the minimum requirements for traceability should include these details: date harvested, date distributed, place of distribution, and how long the product can be kept on the shelf at various retail outlets.

It was obvious from the two workshops that handling systems can vary greatly between farms for many reasons. What’s the same is the need to continually evaluate postharvest operations to improve efficiency, hygiene and food safety.

“Consistent progress is more important than getting it right from the start,” Blanchard said about the efficiency of the handling system.

“Food safety is not just a legal responsibility, but a moral and ethical obligation you have with your customers,” he added, suggesting that related state and federal regulations will be easier to follow if producers strive to continuously improve the quality of their products.

Back to Leopold Letter Winter 2009