Food Protection Connection: New Guidance for Leafy Greens and Melons (Part 2)

(reprinted from Dietary Manager, October 2009)

On July 31, 2009, the FDA released new guidance for ensuring the safety of tomatoes, leafy greens, and melons. Last month Food Protection Connection presented advice for keeping tomatoes safe throughout the supply chain. Now we take a look at leafy greens and melon.

A "Growing" Effort

The new guidance, current in draft format and open for comments, builds on numerous past FDA recommendations, including a 2004 Action Plan for produce safety, 2005 guidelines for melon safety, 2006 guidelines for safety in the lettuce/leafy greens supply chain, and a 2008 Guide to Minimize Microbial Food Safety Hazards of Fresh-Cut Fruits and Vegetables. You may also recall that in August 2008, the FDA amended the food additive regulations to allow ionizing radiation for controlling foodborne pathogens and extending shelflife in fresh iceberg lettuce and spinach.

Industry plays a leadership role as well. In 2006, members of the lettuce/leafy greens industry prepared voluntary recommendations for food safety. In 2007, California farmers formed the California Leafy Green Products Handler Marketing Agreement to “reduce potential sources of contamination in California-grown leafy greens.” The group says it includes 99 percent of California handlers, who have committed to food-safe practices and audits by the California Department of Food and Agriculture in the farming of lettuces, spinach, arugula, kale, chard, cabbage, endive, escarole, and other leafy greens.

Leafy Greens

Following its own 2004 Action Plan, the FDA kicked off a Leafy Greens Safety Initiative in 2006. First steps targeted E. coli O157:H7 associated with fresh and fresh-cut lettuce. Officials expanded efforts to include spinach in 2007, following E. coli outbreaks linked to bagged spinach in 2006.

In a classically HACCP-like analysis, the FDA’s draft guidance breaks down the farm-to-fork chain for leafy greens from production through harvest, postharvest, fresh-cut/ value-added operations; distribution; and consumer, retail, and food service. The FDA now advises dozens of controls, such as: conducting environmental assessments prior to the first seasonal planting, within one week prior to harvesting, and during harvesting operations; locating production sites to minimize potential access by wildlife; performing a sanitary survey prior to the use of water in agricultural operations; monitoring water quality with regular testing; ensuring that water used for spray applications of pesticides is not contaminated; verifying the time and temperature process used during the composting process (for soil amendments); using cleaning verification methods for harvesting equipment; and cooling leafy greens immediately after harvest.

One section of the guidance outlines precautions in the event of flooding, because a flood can introduce cross contamination into growing fields. As with tomato guidelines,the FDA spells out the elements of employee health and hygiene required by people who contact produce through harvesting and processing, to prevent transmission of pathogens from people to food. The FDA presents guidance regarding packing greens in bulk bins and application of modified atmosphere for shipment to processing plants. As with tomatoes, the FDA specifically calls for traceback documentation, i.e., standardized, clear records that can enhance the ability to follow the movement of the product. This is especially important for outbreak investigation.

Holding the Bag

If you’re holding a bag of leafy greens, you have to answer a key question: To wash or not to wash? If you’ve ever been unsure, take heart. The new guidance recommends clear labeling to eliminate confusion about whether a product needs to be washed before consumption. The FDA favors labeling terms such as ‘triple-washed’ or ‘ready-to-eat’. New guidance also reminds us not to puncture bagged greens when taking temperatures. Folding bags over like pillows, with the thermometer in the middle, is a safer procedure. More advice from the FDA, specifically for foodservice operators:

• Don’t use leafy greens with visible signs of decay or damage. These may harbor pathogens.
• Wash fresh produce in water to remove soil and other contaminants before cutting, combining with other ingredients, cooking, or serving.
• Clean and sanitize all food-contact equipment and utensils used with cut leafy greens.
• Wash hands thoroughly before cutting or handling leafy greens, and re-wash hands as necessary.
• Use gloves (changed frequently) or a utensil to prevent cross contamination when handling fresh-cut leafy greens.
• Store and display fresh-cut leafy greens under refrigeration.
• Follow package instructions for the product, such as “best if used by” dates.
• Develop training programs to educate all potential handlers of leafy greens.

Melon

Just how hazardous is fresh melon? From 1996 through 2008, melon-associated outbreaks triggered 507 illnesses and two deaths. Points out the FDA, “Significantly more foodborne illness outbreaks have been associated with melons that have netted rinds. Human pathogens may adhere to, survive on, and be more difficult to eliminate from netted melon rind surfaces.” The primary culprit here is cantaloupe, accounting for about three out of four outbreaks.

While much of the guidance for melon mirrors that for tomatoes and leafy greens—including environmental assessment and controls, worker hygiene, and traceback documentation— there are some unique points to the proposed melon safety rules. The FDA is focusing on how to minimize surface contamination of melons, for example, especially those with netted rinds. Once surface contamination occurs, elimination is very difficult, notes the FDA.

Managing the safety of melons touching the ground during ripening is also a priority. Related rules cover everything from ensuring that soil amendments are safe to sanitizing plastic ground sheets to ensuring hygiene of field workers who turn melons by hand during this process. During and after harvest, the guidelines call for protection from mechanical damage, as cracks and bruises open the door to pathogens. Another focus is implementing postharvest handling practices to minimize stem scar and rind infiltration of foodborne pathogens into edible melon flesh. Furthermore, the FDA raises concerns with a procedure called top icing—covering melons with ice during transport. Melting ice can cause cross contamination within and among pallets of melons, notes the FDA. The guidance offers controls to make this process safer, while also recommending use of alternative cooling methods. As dietary managers already know, cut melon has long been cited as a potentially hazardous food (PHF-TCS). Current FDA guidance calls for maintaining fresh-cut melon products at 32°- 41°F during storage and service to prevent growth of foodborne pathogens. Today, new draft guidance gives operators in the foodservice arena more support behind the scenes, targeting and controlling hazards in produce from farm to fork.

by Sue Grossbauer, RD
Sue Grossbauer, RD, author of several books, is a regular contributor to DIETARY MANAGER magazine.