Keeping Your Greenhouse Vegetables And Fruits Safe: Overview Of Best Food Safety Practices

packaged vegetables
packaged vegetables

by Angela L. Shaw, Christopher J. Currey and Michael R. Evans

Greenhouse and controlled-environment food production can provide year-round supplies of fresh and wholesome fruits and vegetables to consumers. The popularity of local foods and sustainable crop production, along with government efforts to increase fresh fruit and vegetable consumption, has strengthened the demand for fresh fruits and vegetables in the U.S.

In the midst of these positive trends, large foodborne outbreaks associated with fresh, minimally processed and processed vegetables and fruits (melons, leafy greens, peppers, tomatoes, seed sprouts, etc.) have occurred periodically. With every outbreak, the market sees dips in the consumer purchasing patterns of that item. Greenhouse-grown produce is not immune to these threats.

Why The Concern With Greenhouse Production?

It has been estimated that 46 percent of reported foodborne illnesses are attributed to fruits, vegetables and nuts. The majority of these outbreaks can be traced to fields and postharvest processing facilities not following recommended GAPs/GMPs. Greenhouse fruit and vegetable production has been viewed as a positive alternative to field production because of the reduction in concerns related to the environment in general, but more specifically soil, wildlife and natural weather events such as floods. This may be true because the number of foodborne outbreaks related to controlled environment production have been rare.

However, in June of 2014, a multi-state foodborne outbreak of Salmonella Saintpaul was linked to greenhouse grown cucumbers in Culiacán, Mexico, that caused 84 infections and 17 hospitalizations in the U.S. Like the majority of foodborne outbreaks, poor sanitation and not following GAPs/GMPs caused this outbreak. It serves as a reminder that food safety should be a priority in all produce production settings. With consumers becoming more concerned over produce food safety, various governmental agencies have been tasked with providing guidance and regulations.

Understanding The Language Of Food Safety Regulations
Federal, state and local laws are the backbone of food safety management in the U.S. food supply. The Federal Food, Drug and Cosmetic Act of 1938 is the first and largest food safety regulation to date and is the leading act cited during litigation from victims of foodborne illness.

The Food Safety Modernization Act proposed Produce Safety Rule, final ruling October 2015, provides additional mandatory guidance specific to fruit and vegetable growers. This specific portion of the rule focuses on food safety control with: agricultural water; biological soils; worker health and hygiene; domestic and wildlife control; sanitation of equipment, tools and buildings; and training. Water quality and safety definitions (including testing numbers, frequency and interpretation), acceptable bio-solids characteristics and training and documentation requirements for workers, along with wildlife guidance, were provided in the ruling. The ruling echoes many GAPs and GMPs that are commonly followed in the fruit and vegetable industry.

With the introduction of new regulations, an opportunity is created for growers to review their current production, harvesting and handling practices to ensure their crops are safe for consumption and their business is protected from liability. Risk assessment of production and handling facilities should be conducted with an end goal of improving policies, procedures and documentation to reflect high quality and safety standards. Through these improvements, food safety risks of causing foodborne illness are reduced.

Brief Overview Of Food Safety Target Areas
Education about proper fresh produce handling from farm to fork helps prevent food safety contamination on the farm, during packing, processing, distribution and within retail settings. Although there are many variations in production systems, greenhouse food crop safety programs should focus on four main areas: substrate, water, facilities and people. In greenhouse production, substrate includes materials such as coir, peat, perlite, rockwool and phenolic foam cubes. Substrate, like soil, can hold harmful chemicals and bacteria along with physical hazards.

Growers should learn more about the sources of their substrates and the production standards used to manufacture the substrates. Further, within the greenhouse operation, proper storage and handling of the substrates should be practiced to minimize the potential for contaminating the substrate with potentially hazardous chemicals or bacteria.

Water is an essential component in greenhouse food crop production. For example, one way contamination occurs is through the use of municipal water during a boil water warning. In the case of a contaminated water source, is there a back-up plan if your water source becomes non-potable or harmful for consumption? Testing of incoming water and recirculating fertilizer solutions can provide assurance that contamination isn’t occurring on a daily basis.

Other food safety areas of concern include workers and sanitation. Poor equipment and facility sanitation practices and poor design of facility and equipment can introduce unwanted food safety risk into the operation. Worker and visitor standards are another area of food safety concerns. Poor worker hygiene, sickness and visitors can introduce unwanted foodborne bacteria and viruses into the facilities that can contaminate the products through hands, clothing and bodily fluids. Having basic written guidance and policies for workers can reduce inconsistencies in production practices and ensure the safety of packaging finished products.

Angela L. Shaw ([email protected]) is an assistant professor in the Department of Food Science and Human Nutrition at Iowa State University. Christopher J. Currey ([email protected]) is an assistant professor in the Department of Horticulture at Iowa State University and Michael R. Evans ([email protected]) is a professor in the Department of Horticulture at the University of Arkansas.

Topics: , ,

Leave a Reply

More From Edibles...

September 29, 2017

Vertical Farming Looks to Go Mainstream

The University of the District of Columbia is the nation’s only urban land-grant university, so it was a particularly appropriate setting for the Association of Vertical Farming (AVF) to host the AVF Summit 2017 on September 22. The summit was a mix of education, advocacy, and policy discussion about urban agriculture — vertical farming in particular — targeted at finding ways to broaden its adoption in cities around the country and around the world. You’ve probably heard quite a bit in recent months about vertical farming — systems for growing food in stacked layers in completely controlled environments, applying inputs such as light, water, and fertilizer in precise amounts. While there’s some use of these systems in greenhouse settings, in many cases, urban farmers are repurposing abandoned buildings or even shipping containers. Match the availability of these facilities in most large urban areas with big cities’ limited access to fresh, […]

Read More

August 1, 2017

39 New Vegetables and Herbs for 2018

New vegetable and herb introductions for 2017 offer unique shaped fruits, distinctive foliage, intense flavors, improved disease resistance, high yields, and more. Here are 39 new vegetable and herb varieties to consider for your product mix in 2018.

Read More
International Tomato Congress

May 30, 2017

Learn How to Improve Your Greenhouse Tomato Production at the International Tomato Congress

Greenhouse vegetable growers looking for practical information on how to produce better tomatoes should make plans to attend the International Tomato Congress, which takes place July 26-28 in León, Guanajuato, Mexico.

Read More
Latest Stories

September 29, 2017

Vertical Farming Looks to Go Mainstream

The University of the District of Columbia is the nation’s only urban land-grant university, so it was a particularly appropriate setting for the Association of Vertical Farming (AVF) to host the AVF Summit 2017 on September 22. The summit was a mix of education, advocacy, and policy discussion about urban agriculture — vertical farming in particular — targeted at finding ways to broaden its adoption in cities around the country and around the world. You’ve probably heard quite a bit in recent months about vertical farming — systems for growing food in stacked layers in completely controlled environments, applying inputs such as light, water, and fertilizer in precise amounts. While there’s some use of these systems in greenhouse settings, in many cases, urban farmers are repurposing abandoned buildings or even shipping containers. Match the availability of these facilities in most large urban areas with big cities’ limited access to fresh, […]

Read More
Figure 4. The 1801 container was the only tray in the experiment to produce commercially acceptable stalks after 118 days (approximately 17 weeks) of growth

February 21, 2016

Feasibility Of Hydroponic Celery Production

An experiment with growing ‘Tango’ and ‘Tall Utah’ cultivars in various plug tray sizes explores whether hydroponic production is suitable for celery with its long crop times.

Read More
Prewashing surfaces and produce can reduce debris in wash solutions.

June 27, 2015

Keeping Your Greenhouse Fruits And Vegetables Safe: San…

The last article in the four-part food safety series highlights sanitation training, policies and protocols to maintain for an effective and successful food safety program.

Read More
Figure 1. Pak Choi grown in a deep plug tray on a flood and drain bench.

June 26, 2015

The Intrigue Of Edible Petiole Crops For Hydroponic Pr…

In a twist to traditional field production, experiments with petiole crops Pak Choi, kale and Swiss chard determine their suitability for hydroponic production systems using plug trays.

Read More
Syngenta Vegetable Trial Overview

June 25, 2015

Vegetable Trials Test Variety Adaptability In Contain…

How do crossover varieties normally grown by fresh market farmers, and now available to home gardeners, perform in patio containers? Vegetable container trials at Syngenta Flowers show surprising results.

Read More
GMO free USDA Organic pepper

June 22, 2015

Study: Many Consumers Unwilling To Waver On GMOs

According to a new University of Florida (UF) study, even when armed with new information, many people won’t change their minds about genetically modified foods.

Read More
GMO-free labeling is just as important for the consumer as organically grown labeling, according to Leigh Ann Centeno of Parks Brothers Farm.

June 22, 2015

Parks Brothers Launches Peace Farm Organics Line Of E…

For the last 10 years, Parks Brothers Farm in Arkansas (No. 92 on Greenhouse Grower’s Top 100 List in 2015) has been considering the possibilities for launching a line of organic vegetables and herbs, but it wasn’t until 2013 that the operation started to get serious about it.

Read More
GMO free USDA Organic pepper

June 21, 2015

Non-GMO Label Helps Great Lakes Growers Stay Ahead Of T…

When Great Lakes Growers made the decision to become non-GMO certified earlier this year, it wasn’t for philosophical reasons, nor was it to make a higher profit. Rather, says Tim Ryan, co-partner at Great Lakes Growers along with John Bonner, it was completely consumer driven.

Read More
Tomato 'Think Pink' (Sakata Vegetables)

May 18, 2015

3 Questions To Ask Before Purchasing A Digital Food Saf…

If you're thinking about moving from a paper system to a digital system for food safety recordkeeping, asking yourself these three questions will help you decide what type of system you want and what is actually needed.

Read More
tomatoes packaging_JeremyKeith_Flckr

May 11, 2015

Keeping Your Greenhouse Vegetables And Fruits Safe: Foc…

In part two of a four-part food safety series, learn how to keep food safety risks low by following proper water testing procedures and maintaining safe storage practices for substrates and food packaging materials.

Read More
Zucchini 'Brice' (Syngenta Vegetables)

April 14, 2015

18 New Vegetables For Easy Growing And Healthy Eating

Current breeding efforts have focused on vegetable varieties that cater to small space and urban gardening trends and offer consumers good performance with minimal efforts. As a result, new, easy care vegetable introductions packed with flavor and loaded with fruits have swept onto the market. Here are 18 of the newest vegetables already on the market or hitting the market in 2016.

Read More

April 13, 2015

Keeping Your Greenhouse Vegetables And Fruits Safe: Ove…

This is the first installment of a four-part series that will bring you up to speed on what it takes to fulfill food safety mandates for greenhouse production.

Read More

April 10, 2015

5 Selection Principles For Vegetables That Sell

You gain a competitive edge when you select vegetable varieties that are right for your greenhouse and right for your customers. Here are five pieces of advice from breeders to help you stay ahead of the game.

Read More

June 26, 2014

California Spring Trials: 10 New Edible Varieties To Co…

Breeders at California Spring Trials presented edibles in container gardens, urban gardens and mixed combos with ornamentals. New colors, sizes and flavors make these featured edibles a fresh tastebud experience. Here are 10 new varieties to pump up the flavor power.

Read More