Handle with care

Hands-on experience, on-line tools give Iowa fruit and vegetable growers new perspective on postharvest handling, food safety.

By Malcolm Robertson

All photos by Jerry DeWitt Chard bunched, washed and awaiting packing at Chris Blanchard's farm.

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

The Iowa Fruit and Vegetable Working Group conducted two workshops recently that highlighted postharvest handling of vegetables, wholesale sales and preparing produce for market.

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 also discussed food safety issues.

The working group also launched a new Postharvest Handling Decision Tool, a Web site where producers can step-by-step details much of which was presented at the workshops (see sidebar).

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, handlings systems, hygiene and food safety and traceability

Startup and time commitment

Initial costs for a post-harvest handling facility can range from a low of a few hundred dollars for an open-air, outside facility. Proposed food safety regulations are likely to change the way that vegetable operations manage their post harvest operations, and may include additional investment to upgrade facilities.

At both farms hosting the workshops, the postharvest handling facilities have changed to handle 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 business in 1999 he did all postharvest processing in a small high tunnel structure.

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 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 can then be more accurately determined to handle produce flow and labor requirements.

The new packing facility at Rock Spring Farm.

At Black’s Heritage Farms, Norine Black told workshop participants that they need to be continually thinking 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 repeat 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

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.

“This is most probably one of the most controllable areas in the whole process and through this basic hygiene a potentially large contamination problem can be eliminated,” said Iowa State University Extension food safety specialist Sam Beattie. He said improper handling of produce can provide an environment conducive to contamination, which can result in the transmission and spread of bacteria to food, equipment and surfaces throughout the packing shed.

From the day they are hired, employees should be instructed to arrive at work with clean clothes and hands and maintain a strict hygiene regime throughout the day.

“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.

According to Beattie, quality control for produce begins in the field. Any produce contaminated with fecal matter from any animal, including birds, should be discarded.

“No amount of cleaning or disinfectant would eliminate the bacterial infestation on that produce,” he said. “The use of a disinfectant in the water is not to sanitize the product but rather to reduce the bacterial populations in the water.”

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.

“Food safety is not just a legal responsibility, but a moral and ethical obligation you have with your customers.” ~ Chris Blanchard, Rock Springs Farm

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.

Malcolm Robertson is a co-leader of the Fruit and Vegetable Working Group and a program specialist at the Leopold Center for Sustainable Agriculture. His background is in applied economics and he is a native of Zimbabwe, where he worked in production horticulture for export.