One of the many benefits that Americans and other citizens of developed countries enjoy is the relative safety of their food supplies. In 2014, a study conducted by the Conference Board of Canada ranked the top countries for food safety performance.[1] Not surprisingly, the top tier included countries like Canada, France, Ireland, Norway, the United Kingdom and the United States. Reports like this instill a strong level of trust in food purchased and consumed in those particular countries, but is that trust really deserved?
As reported in a Food Safety Magazine eDigest article in January 2016, a total of 626 food recalls occurred in 2015 based on U.S. Food and Drug Administration, U.S. Department of Agriculture (USDA) and Canadian Food Inspection Agency reports.[2] As usual, food allergen issues made up the bulk of the recalls. The allergens involved in the recalls included:
• Milk/dairy: 82
• Peanuts: 49
• Eggs: 42
• Wheat/gluten: 34
These numbers include not only cross-contamination but also, in many cases, labeling issues where product was packaged in the wrong container. Failure to monitor label and package updates also contributed to these recalls.
Yet, with all the high-profile public recalls that are, many times, sensationalized in media reports, the general public is very trusting of the wholesomeness of most foods, including ready-to-eat (RTE) foods.
RTE Challenges
RTE foods pose a whole separate set of challenges when it comes to food safety. One can argue that if someone doesn’t properly and completely cook foods like chicken, beef or fish, there is the potential for contamination from bacteria, nematodes, etc. But if a consumer purchases food that is designed to be edible without further processing, he or she expects it to be safe.
Think about it. When you purchase an RTE food at a grocery store, at a restaurant or from a street vendor, you typically don’t stop to think about whether it will cause some sort of harm or make you sick. If you’ve ever visited a foreign country with inherent sanitation or clean-water issues, you may need to pick and choose what you eat or drink and actively avoid certain venues. You just don’t need to do that in most areas outside of the third world.
But in the United States, Canada and most other developed countries with strict food sanitation laws, the “obligation of prevention” is automatically assigned to the food provider, whether a food processor, a restaurateur or a street vendor.
What is the “obligation of prevention?” If a food handler produces a product that is understood to receive no further treatment to prevent hazards of any type, that business must understand that the consumer will believe the product is safe to consume. That is an awesome responsibility for any processor of RTE foods. And it is one that many processors don’t necessarily take as seriously as they should.
The Difficulty of Defense: An Example
Let’s consider a food that nearly everyone loves: ice cream. Ice cream is a very popular RTE food that can be a real food safety challenge, to say the least. It’s consumed by people of all ages and backgrounds, including those who might be immune-compromised, allergic, pregnant or otherwise susceptible from a health standpoint. But let’s look at some recent ice cream recalls: deaths and illnesses due to Listeria monocytogenes and countless withdrawals from the market resulting from adulteration from unlabeled allergens or other ingredients.
Is this because ice cream processors are inherently sloppy? Or that ice cream is an innately unsafe food? Hardly! Ice cream products, like all dairy foodstuffs, are some of the most regulated foods on the market. And due to the history of ice cream-related food safety recalls and negative publicity, processors are hypersensitive to the associated liability.
Take a look at the frozen-dessert section of your local supermarket. The large variety of products is almost overwhelming: full-fat ice cream versus reduced-fat ice cream; sandwiches, low-carb offerings, sorbets and sherbets; not to mention goodies with peanuts, tree nuts, gluten, eggs, soy and, of course, milk, which is taboo in water-ice products and sorbets. I’m using frozen desserts in my examples, but the same principles can be applied to most RTE foods, especially those with complex product-mix production runs.
These products are not typically produced on separate, sterile lines in plants that have completely separate environments. Yet, they are RTE foods that are deemed to be safe by anyone who consumes them, even those who aren’t predisposed to some malady. What kind of defense do processors have against cross-contamination and potential liability?
There’s an old adage that says “The best defense is a good offense.” This especially applies in this case. Food processors need to go on the offensive to defend themselves against recalls caused by the adulteration of their RTE foods. They need to protect their products at all levels, starting in the manufacturing environment.
Segregation of RTE Zones
In most food processing plants, there are various areas or “zones” that can be separated based on their use and level of food handling. Ingredient intake areas are typically considered raw zones and should be treated as probable sources of bacterial contamination. Personnel working in these areas should be restricted to this zone and not be permitted to enter other areas of the plant, especially RTE areas.
Food plants typically use color-coded schemes to separate the use of cleaning utensils such as brushes and cleaning buckets. The same can be done with personnel attire in finished-product handling zones. Various-colored jumpsuits can be used for permanent employees to indicate the same separation. In addition, different-colored hairnets and disposable smocks can be used for both visitors and permanent employees moving from one product zone to another.
Environmental swabbing for pathogens should be more frequent and more vigorous in areas where cross-contamination of RTE products could occur. Some of the more robust swabbing regimes utilize a zone concept to identify the level of cross-contamination risk present from one area of a food plant to another.
Based on the susceptibility of an RTE food that may be exposed to the food processing environment, one can assign zones as follows:
• Zone 1 is the most sensitive to contamination: typically, a product-contact surface. Positive, confirmed pathogen results in this zone would be considered a food safety hazard and would render finished product adulterated. Finished product that has been inadvertently released to the market prior to receiving a positive result would almost surely lead to a product recall.
• Zone 2 is an area that is in “close proximity” to a product contact surface and is less susceptible to contamination than Zone 1 (but still of high concern). External factors (personnel, water, air, equipment) could easily transfer pathogens from Zone 2 to Zone 1.
• Zone 3 is an area of lesser importance and with a reduced chance of contamination for an RTE product. However, based on traffic patterns, air movement and other vector concerns, identification of pathogens in these areas is of moderate concern.
• Zone 4 is used by some food processors but not by all. There’s a valid debate about how effective it is to swab things like dumpster areas, bathrooms, etc. Proponents say there is always a potential of tracking pathogens from one of these areas into a more critical area, but others feel it’s akin to finding some type of crawling creature if you turn over a rock in a desert. You may not find anything, but don’t be overly surprised if you do.
Preparation of “Natural” RTE Foods
The whole attractiveness of RTE foods versus anything that requires increased preparation is the savings of time and effort. Consumers are living in a world of constant hustle and limited time, being driven by obligations around work, school, kids and endless other activities. Yet, some people hold the opinion that the preservatives and additives in quick, convenient RTE foods render them unwholesome and inferior to fruits and vegetables or other natural foods.
Consider a food like the banana. Some people consider bananas one of the healthiest foods available. They are the most popular fruit in the world. And according to USDA, bananas have overtaken apples as the most widely consumed fruit in the United States. From a nutritional standpoint, bananas are high in potassium and pectin (fiber) as well as magnesium, vitamins C and B6, and antioxidants. What’s best about bananas is that they have their own natural seal to protect them from the elements. Seemingly the “perfect” RTE food, right?
But even bananas get a bad rap from many food purists. Bananas are grown in parts of the world that are hot, humid and full of invaders like insects, mold spores and nematodes.
There are a few insecticides, fungicides and acaracides (mite killers) that are regularly used on bananas. Surprised? Don’t be. Your display of bananas at the supermarket would be a bit more fuzzy without them, and you would be paying much more for less attractive fruit.
Chlorpyrifos is an organophosphate insecticide, acaracide and miticide that has been used to impregnate plastic bags draped over the banana bunches that hang from the banana plant (Figure 1).
The chlorpyrifos that is embedded in the blue plastic bags essentially dissipates long before the bags are removed at harvest time. The use of white bags typically indicates the lack of pesticide incorporation.
The banana bunches are cut down from the plant and taken to the nearby packing station. At the packing station, the bunches are separated into clusters, which are what you see on display at the grocery store. This is when the crown of the cluster (the point where the individual bananas connect to each other) is sprayed with (or dipped in) fungicides such as thiabendazole and imazalil. Without this treatment, rapid mold growth on this part of the banana cluster is highly likely. Studies have shown that the outer peel of the banana protects the edible portion from contamination, although many organic proponents obviously disagree.
Modified-Atmosphere Packaging of RTE Foods
While we’re on the topic of bananas, let’s look at how RTE foods are specially shipped or packaged to improve shelf stability. Modified-atmosphere packaging (or MAP) of bananas with ethylene, carbon dioxide and special moisture-scrubbing packaging can greatly reduce the ripening effect and prolong shelf life.
MAP is a means of controlling (i.e., slowing) the microbial or enzymatic action on foods that leads to discoloration or spoilage. Although conventional methods of slowing spoilage like refrigeration, pickling, culturing, curing, etc. have been used for a very long time, MAP is an alternative that doesn’t greatly affect the normal organoleptic qualities of the food.
As an example, fresh fruit and vegetable products, packaged in special foil packaging, may be flushed with gas mixtures such as 90 percent nitrogen, 5 percent oxygen and 5 percent carbon dioxide to provide the ideal environment to extend shelf life. As a comparison, the normal composition of air is 78 percent nitrogen, 21 percent oxygen, 0.03 percent carbon dioxide and traces of noble gases. As you can see, the relative level of oxygen is greatly reduced.
Reducing the oxygen level prolongs the shelf life of RTE foods such as fruits and vegetables by delaying the oxidative breakdown of some key components of the product. Reduction of oxygen concentrations (< 8%) also helps reduce the production of ethylene, which is part of the natural ripening process.
So why not flush all the oxygen out of the packaging? At very low oxygen levels, anaerobic respiration can occur. Not only might this lead to product tissue destruction, but it can also lead to the production of unfavorable metabolites that contribute to off flavors and off odors. Even worse, anaerobic conditions can lead to the potential growth of foodborne pathogens such as Clostridium botulinum.
There has been some experimentation by packers of fresh green vegetables in the United Kingdom who have been testing oxygen mixtures between 70 percent and 100 percent. This application has been found to be very effective in inhibiting enzymatic discoloration as well as both aerobic and anaerobic microbial growth. However, there have also been reports that elevated oxygen levels (around 80–90%) may actually stimulate the growth of foodborne pathogens such as Escherichia coli and L. monocytogenes. So look to more and more innovation in the use of MAP to extend the shelf life of RTE foods.
No discussion of RTE foods would be complete without mentioning foodservice channels, specifically restaurants. According to a U.S. Centers for Disease Control and Prevention (CDC) study, norovirus was found to be the most common foodborne disease agent, accounting for 42 percent of all confirmed foodborne outbreaks during the study period.[3]
Handling of food by an infected person or carrier (65%) and bare-hand contact with food (35%) were the most commonly identified contributing factors.
A separate study identified potential environmental factors as part of 154 foodborne illness outbreak investigations in foodservice establishments. The following data were published by the CDC3 as preliminary findings:
• The majority (84%) of the foodservice establishments involved in the outbreaks were complex establishments, meaning a complex food handling process is utilized for one or more foods handled in the establishment. Additionally, 13 percent were cook-serve establishments, and 3 percent were prep-serve establishments.
• Spanish was the primary language of 58 percent of food workers, but only 41 percent of managers could speak Spanish.
• Floor-cleaning policies existed in 95 percent of establishments, but only 37 percent of these policies were written.
• Fewer establishments had policies on cleaning of food contact surfaces (88%), cutting boards (89%) and food slicers (72%).
• More managers (66%) received paid sick leave than workers (35%).
• The majority (96%) of establishments had hand sinks available in employee restrooms and work areas (94%). However, hands-free-operated sinks were rare (restrooms: 4%; work areas: 3%).
Summary
In summary, RTE foods are becoming a growing percentage of the overall food sales market. Innovation in processing and packaging is contributing to the number of applications for types of products and channels for sale. Demands by consumers for foods that are healthy, organoleptically acceptable after extended periods and safe for consumption continue to drive the current market trends.
Consumers have a high degree of confidence in the safety and wholesomeness of foods that are presented for sale as RTE. Food processors and other food handlers have a legal and ethical responsibility to ensure there is no breach of that trust. Processors of RTE foods must remember that their employees are the last point of contact with that food prior to its being consumed by the end-user. This is a huge responsibility that can’t be discounted.
The incorporation of preventive controls (e.g., Hazard Analysis and Critical Control Points), as required by the Food Safety Modernization Act, is a key component in a food safety program that helps prevent the adulteration of RTE foods. This is true not only at food processing plants but also in foodservice channels.
So whether dealing with fresh fruits and vegetables, canned goods, liquid beverages, frozen treats, baked goods, prepared meat snacks, chilled foods, confections, foodservice items or any of the other growing number of RTE foods, the common objective with all of them is protection against adulteration. It protects your consumers, your shareholders, your brand, your reputation and your business.
Thomas Sauer is a quality & food safety consultant and a charter member of the Editorial Advisory Board of Food Safety Magazine. He has held positions in quality assurance, food safety and operations with companies such as Chiquita, Kraft, Unilever and Wells Enterprises. He can be reached at tmsauer@gmail.com.
References
1. www.conferenceboard.ca/cfic/research/2014/foodsafety.aspx.
2. www.food-safety.com/enewsletter/a-look-back-at-2015-food-recalls/.
3. www.cdc.gov/nceh/ehs/ehsnet/foodborne_illness_outbreaks.htm.
