“Quick, fast and in a hurry” is the decree of contemporary American consumers when it comes to food products. They demand instant gratification and instantaneous satisfaction from the foods they purchase. This demand has not eluded the marketing heads and product developers of leading food companies. Indeed, these companies have rushed to the marketplace with every form of convenience food conceivable. The refrigerated and frozen food aisles of most supermarkets are brimming with foods that are intended for a “quick fix” or that can be made in a substantially shortened preparation time. There are TV-type dinners of enormous complexity and gastronomic sophistication aimed at quickly satisfying the epicurean desires of increasingly busy and urbane consumers. There are sauces in jars that “only” require the addition of meat or vegetables. There are pasta meals in boxes or bags that only require heating. There are pot pies, frozen pizzas, meat sandwiches, ready-to-cook (RTC) and nearly ready-to-eat (RTE) foods filling the shelves of America’s supermarkets. These foods, in many instances, are high-end and result in high margins for those companies that successfully place them.

However, the fast-growing convenience foods category is a growing concern for food safety practitioners and public health officials. A significant source of concern has to do with the labeled instructions for the preparation and handling of these sensitive foods, particularly in the not-ready-to-eat (NRTE), or RTC, product category since these require cooking by consumers as the ultimate food safety assurance. In the past year there have been at least two major foodborne illness outbreaks attributed to the consumption of undercooked convenience foods that contained pathogenic microorganisms. As a result, the food industry is revisiting how it develops consumer cooking instructions for these categories in the context of validating the cooking methods provided to consumers on product labels.

Both the Grocery Manufacturers Association (www.gmaonline.org) and the American Frozen Food Institute (www.affi.org), for example, have drafted guidelines for their members producing NRTE foods, outlining standardized protocols for the validation of consumer cooking instructions and encouraging food manufacturers to ensure that label text is clear, concise and helpful to the consumer in achieving a fully cooked product, whether that is conducted in a conventional appliance, such as an oven or toaster oven, or in a microwave oven. These organizations shared this information at the International Association for Food Protection-sponsored Timely Topic workshop, “Prepared, But Not Ready-to-Eat Foods: What You Need to Know,” in January, where the participating food companies, regulators and scientists made the case again and again for validation of any protocols used in the development of such instructions.

The Challenge of Cooking Instructions
Imagine an exquisite chicken cacciatore sauce, formulated with the finest ingredients and offered as part of a complete meal in minutes. The label instructions might read something like: 1. Sauté pieces of boneless chicken in hot oil until lightly browned; 2. Reduce the heat and add the cacciatore sauce; and 3. Heat the sauce and meat mixture until done. The outcome of this meal may be more than the consumer bargained for—at least from a food safety perspective. It is highly likely that those eating this meal will later present at the emergency room of the local hospital with symptoms of a gastrointestinal disease consistent with a diagnosis of acute salmonellosis or campylobacteriosis. Another unintended outcome of these flawed cooking instructions is the likelihood of litigation.

There has been a long running debate among food safety scientists as to whether or not food labeling, specifically as it relates to cooking or serving instructions, should be considered a critical control point in terms of Hazard Analysis and Critical Control Points (HACCP). Some argue that HACCP is completed at the end of the production line; i.e., when the producer no longer exerts control over the processes that are critical for preserving the safety of the processed food. Others have argued that the food packaging, especially the labeling of those foods known to contain sensitive ingredients, is a critical control point. The U.S. Department of Agriculture’s (USDA) Safe Handling Guidelines, as contained in or on labeling of raw meat and poultry, are very much an expression of this latter point of view. In the aforementioned example involving chicken cacciatore, the food processor should have been more diligent when preparing the cooking instructions, owing to the well-established fact that raw chicken is known to contain pathogenic bacteria. Simply saying “cook until done” in not sufficient for food safety; a more prudent approach might involve offering cooking times and temperatures, in the instructions, that are proven to inactivate the undesirable microorganisms.

The food safety concerns associated with convenience foods may further be exacerbated by the widespread usage of microwave ovens. It is interesting to observe that with the penetration of microwave oven into America’s kitchens, there is what appears to be a corresponding increase in the number of cases of trichinellosis. Between 1947 and 1967, the Centers for Disease Control and Prevention (CDC) surveillance data show a precipitous overall decline in pig-mediated trichinosis in the U.S. The observed decline of this pernicious, parasitic disease in humans was due in large measure, according to public health officials, to changes in on-farm practices related to housing, feeding and implementation of improved standards of care for swine prior to slaughter. Public health officials and veterinarian advised farmers against feeding the animals garbage and also of the need for preventing the pigs from exposure to rats—an important vector in the transmission of the disease. Concurrent with these on-farm developments, public health officials, home economics teachers, gym teachers and librarians across the land were enrolled in an unprecedented campaign to educate the public of the perils of eating undercooked pork.

In the period 1967 to roughly 1979, CDC surveillance data show large spikes in the reported cases of trichinellosis in the U.S. The case load levels observed during this interval were consistent with those observed in the 1950s (Figure 1). This period of increased disease activity corresponded with the increased uptake and use of microwave ovens by American consumers. According to J. Carlton Gallawa, in A Brief History of the Microwave Oven, prior to 1967 only about 14% of U.S. households were using microwave technology. However, during the interval 1975-1978, more than 60% of U.S. households owned microwave ovens. During this time frame the number of cases of trichienellosis went from less than 100 reported cases in 1967 to nearly 300 cases in 1975. This trend continued until about 1980 when the USDA issued guidelines for cooking pork in microwave oven (internal temperature of greater than 170F). With the advent of these cooking guidelines the trend line for the number of trichinellosis cases fell off sharply so that they were again consistent with the observed caseloads prior to 1967. These are not hard and fast data; rather they are conclusions that have been drawn by various workers who have investigated the apparent anomalies in the downward trend of pig-borne trichinosis in the U.S. These data are at least suggestive of a casual relationship between the microwave oven and the incidence of trichinosis.

The USDA recommendations notwithstanding, it is generally recognized that microwave heating of foodstuffs is not uniform and consistent. The results of a study published in 1983 by W.J. Zimmerman in which he studied the inactivation of Trichinae in artificially infected pork roast show that this lack of uniformity in heating resulted in the recovery of infective Trichinae, after cooking, in 50 of 189 pork roasts. This worker also reported recovering viable Trichinae from a roast in which five temperature measurements from different areas of the roast exceeded 76.7C. Zimmerman also reported the recovery of the infectious agent from pork roast that appeared to be well done. Similar findings have been reported by Ribicich. These and many other studies in the NRTE food category show that it is common practice to observe cold spots in foods that have been heated or cooked using microwave technology. It is precisely for this reason that food companies need to prospectively validate the cooking instructions provided on the labeling of their products.

Validation of People, Process, Product
Validation is the process of providing objective data that confirms with a high degree of confidence that a process or procedure will consistently yield the desired outcomes. In terms of cooking instructions this means ensuring that the prescribed methods will consistently produce a food that will not cause harm to the end user (i.e., safe food). Yes, this is a very difficult chore since validation must take full measure of the people involved with cooking and preparation of the food, the processes used including the capability of the cooking/heating equipment and of the physical characteristics of the food products that are being treated. In the final analysis validation is about understanding the sources and relative magnitude of the variation inherent to or associated with a specific process.

People. Consider a 13-year-old boy who arrives home from school, hungry and in a hurry, who places a pot pie into the microwave. This is potentially a dangerous situation, depending on the nature and composition of the food. The danger is amplified if the food contains a sensitive ingredient (i.e., raw meat, chicken or vegetables) that are known to contain human pathogens. In this worst-case scenario it is not only likely but most probable that the child will not read the labeled cooking instruction; rather he will most likely place the food into the oven and cook it until it appears done (e.g. hot and bubbling). The food scientist responsible for developing the product and its cooking instructions must take this behavior into account in the context of conducting the validation process. Realizing this behavior as a possible outcome, the food company might be inclined to reformulate its product so as to eliminate the sensitive ingredients. Alternatively, the company might elect to allocate space on the label’s principal display panel for communicating—boldly—the proper cooking instructions.

Another point related to consumers that must be considered in the context of the validation process has to do with confusion in differentiating between RTE foods and foods that are RTC. Precooked, RTE foods only require heating. By contrast, ready-to-cook, or NRTE, foods, especially those that contain a sensitive ingredient, require thorough cooking. The distinction between the two types of foods must to be clearly communicated to the end user. This situation is likely complicated for consumers when there are both ready-to-eat and ready-to-cook variants of the same product in the marketplace,such as precooked pot pie and uncooked pot pies. Failing to cook a food that contains a human pathogen will likely have dire consequences for both the consumer and the company responsible placing the food in the trade.

Process. Understanding the capability and limitations of the microwave technology is perhaps the biggest and most important challenge in terms of process validation. Placing a food in a microwave oven, adjusting the power setting and exposure time are the fundamentals of operating a microwave oven. Behind these setting and adjustments, however, is a world of variation when it comes to heating food products.

First, there is great inherent variation among microwave ovens. Even when comparable devices are operated at the same power and time settings the end results are not always equivalent or predictable. We’ve all experienced the cold spot phenomenon in microwave-treated products. Product and recipe developers responsible for generating cooking instructions require a rudimentary knowledge of the science and theory of microwaves. More importantly, owing to the high levels of inherent “common cause” variability in microwave oven technology, they will require access to multiple microwave ovens from different manufactures for inclusion in the execution of the validation protocols. Performance characteristics of the various ovens must be considered when cooking and or heating instructions are being developed.

It is also important for the product development staff to include microbiologist and engineers on the process validation team. In the final analysis, the aim of the validation protocols is the establishment of those exposure times and temperatures that will be efficacious in eliminating or reducing to acceptable levels those pathogenic organisms likely to be associated with the food that is being investigated. The role of the microbiologist or engineer is analogous in some respects, especially for those foods that contain a sensitive ingredient, to the role of the process authority in food canning operations.

Product. Ultimately, the act of validating cooking instructions is about ensuring the safety and quality of the food. Food processing companies are, after all, in the business of selling food. It stands to reason therefore, in terms of validation, that it is the food itself that requires the highest level of scrutiny. Frozen foods, frozen foods with particulates, refrigerated foods, RTE foods and RTC/NRTE foods are very different propositions when it comes to cooking instructions. The realities of the modern marketplace make it an imperative that foods offered for sale are competitive. They must also be safe.

Convenience is a very attractive selling point, and therefore is appealing to marketing types and others in the corporation who are preoccupied with profit and loss (P&L) performance. Recent product failures demonstrate the potential of food safety issues to adversely affect bottom line performance. Brand managers must be willing to embrace or accept product performance critiques from disparate groups within the business, especially the admonitions of the food safety officer when there is concern for public health. The product must meet or exceed all regulatory requirements related to public health and safety. Moreover, the company must ensure that its products will perform at the point of use and not represent a hazard to the common man. If the marketing campaign believes that a product’s unique selling proposition (USP) is related to shortened cooking time, then the company must assure that those shortened cooking instructions are consistent with food safety. Microwaving a frozen entrée is potentially more perilous than microwave cooking of a plain cheese pizza. Likewise, cooking a pork roast in a microwave oven poses inherently higher risk than microwave cooking a pasta-based vegetarian meal. In either case, however, it is crucial that company-recommended cooking instructions are proven safe and effective.

From experience, the primary causes for the failure in validating cooking instructions result from disconnects among the various functions within the corporate structure. The validation process works best when it is executed by a multidisciplinary team. As previously noted, the product development and recipe development teams should invite the specialist skills of a microbiologist and engineer to the validation process. Likewise, consideration should be given to involving representatives from consumer sciences and packaging on the team. Each of these disciplines will bring a unique but critical perspective to issues that need be considered in the context of the validation process.

In many corporations the responsibility for review and approving label copy resides exclusively with Regulatory Affairs. Unfortunately this approval scheme is focused on those regulations that pertain to label copy content and format. That is, a focus on element such as net content declaration, the food ingredients declaration and the food nutritional declaration. The mechanics of this scheme does not allow for consideration or treatment of food safety related concerns, other than perhaps allergens. A better label approval process would require the involvement of the Product Safety Officer working with the Regulatory Affairs unit.

Case Closed: Validation Starts at the Top
Frequently, marketing professionals within a food company will pressure the company’s research and development (R&D) members to make unscientific decisions about products and their performance characteristics. That is, marketing managers have a vision and an expectation of product performance that may not always be attainable or realistic. Meal preparation and cooking instructions are a tipping point where the dichotomy between R&D and Marketing may be at its zenith. The terms “quick” and “convenient” are frequently cited in the marketing campaign as critical elements of the USP. Therefore, brand managers are reluctant to embrace or accept a negative critique from R&D or the food safety office. This is a recipe for disaster. Achieving food safety requires close collaboration between and among the many disparate groups within the corporate structure. Cooking instructions, especially those for foods that contain sensitive ingredients, must withstand the rigorous scientific scrutiny demanded by a properly constructed and executed validation protocol.

Ultimately, the responsibility for food safety failures must be placed at the feet of the corporation’s chief executive. He or she has a fiduciary obligation to the board and stockholders. This responsibility—in a company whose primary source of revenue is derived from the sale and marketing of human food—must include oversight and planning for food safety. Food safety failures, as can be seen by the historical record, are business failures that adversely impact bottom-line performance. Moreover, food safety failures cause consumers to lose confidence in a company and its brands. This loss of goodwill frequently becomes a market advantage for the competition.

Larry Keener is the owner and general manager of International Product Safety Consultants (IPSC). Founded in 1996, IPSC specializes in global food safety, microbiology, regulatory affairs and crisis management for multinational food companies. Prior to founding IPSC, Larry served as the director of Product Safety and Regulatory Affairs for Van Den Bergh Foods, Unilever’s largest food products company worldwide. He is an active member of the Institute of Food Technologists and the International Association of Food Protection, and serves on the Editorial Advisory Board of Food Safety Magazine. He is also a member of the Food Science and Nutrition Faculty Advisory board at Tuskegee University, a founding member of the Global Harmonization Initiative, and a business development executive and process validation authority with the National Center for Food Safety and Technology, Illinois Institute of Technology. He can be reached at Lkeener@aol.com.

CDC. Trichinosis surveillance, 1984. MMWR, 35:11SS-15SS. 1986.
Gallawa, J.C. A brief history of the microwave oven. www.smecc.org/microwave_oven.htm
Ribicich, M., et al. 2004. Efficacy of microwave cooking to inactivate Trichinella spiralis larvae in pork. Veterinaria Argentina (21).
Schantz, P.M. 1983. Trichinosis in the United States–1947-1981. Food Technology.
Schubert, H. and M. Regier. 2005. The Microwave Processing of Foods. Chapter 15, Improving the heating uniformity in microwave processing. Woodhead Publishing.
Zimmermann. W.J. 1983. Evaluation of microwave cooking procedures and ovens for devitalizing Trichinae in pork roasts. Journal of Food Science 48(3).