Food Allergen Management

Food Allergens

A food allergy is an adverse immune response to certain kinds of food. They are distinct from other adverse responses to food, such as food intolerance, pharmacological reactions and toxin-mediated reactions. The protein in the food is the most common allergic component. These kinds of allergies occur when the body's immune system mistakenly identifies a protein as harmful. Some proteins or fragments of proteins are resistant to digestion and those that are not broken down in the digestive process are tagged by the Immunoglobulin E (IgE). These tags fool the immune system into thinking that the protein is an invader. The immune system, thinking the organism (the individual) is under attack, sends white blood cells to attack and that triggers an allergic reaction. These reactions can range from mild to severe. Allergic responses include dermatitis, gastrointestinal and respiratory distress, including such life threatening anaphylactic responses as biphasic anaphylaxis and vasodilation; these require immediate emergency intervention. Individuals with protein allergies commonly avoid contact with the problematic protein. Some medications may prevent, minimize or treat protein allergy reactions. There is no cure. Treatment consists of either immunotherapy (desensitization) or avoidance, in which the allergic person avoids all forms of contact with the food to which they are allergic. Areas of research include anti-IgE antibody (omalizumab, or Xolair) and specific oral tolerance induction (SOTI), which have shown some promise for treatment of certain food allergies. People diagnosed with a food allergy may carry an injectable form of epinephrine such as an EpiPen, or wear some form of medical alert jewelry, or develop an emergency action plan, in accordance with their doctor.

                                                                                                

Each year, millions of people have allergic reactions to food. Although most food allergies cause relatively mild and minor symptoms, some food allergies can cause severe reactions, and may even be life-threatening and there is no cure for food allergies. Strict avoidance of food allergens and early recognition and management of allergic reactions to food are important measures to prevent serious health consequences. A food allergy may affect the skin, the gastrointestinal tract, or the respiratory or cardiovascular systems. Many types of foods can be allergens, but certain foods are much more likely than others to trigger an allergic reaction.

Symptoms of Food Allergies

Symptoms of food allergies may range from mild to severe and they may come on suddenly or develop over several hours. Because a person's immune system may react to a very small amount of the allergen, food allergies are particularly dangerous and potentially life threatening, especially if breathing is affected. Because of this, people with asthma are at an increased risk for a fatal allergic reaction to food.

Mild symptoms related to a food allergy may include:

Sneezing

Stuffy or runny nose

Itchy, watery eyes

Swelling

Rash

Stomach cramps

Diarrhea

Severe symptoms of an allergic reaction to food are:

Difficulty breathing, including wheezing

Swelling of the lips, tongue or throat

Hives (an itchy, blotchy and raised rash)

Dizziness or faintness

Nausea or vomiting

Major Food Allergens

While more than 160 foods can cause allergic reactions in people with food allergies, the law identifies the eight most common allergenic foods. These foods account for 90 percent of food allergic reactions, and are the food sources from which many other ingredients are derived.

The eight foods identified by the law are:

Milk

Eggs

Fish (e.g., bass, flounder, cod)

Crustacean shellfish (e.g. crab, lobster, shrimp)

Tree nuts (e.g., almonds, walnuts, pecans)

Peanuts

Wheat

Soybeans

These eight foods, and any ingredient that contains protein derived from one or more of them, are designated as “major food allergens” by FALCPA.

                

Milk Allergies

A milk allergy is a reaction to whey or casein, the proteins found in cow's milk. It’s not the same as lactose intolerance. Milk allergies have been studied more than any other food allergy. The bad news is that children with milk allergies are much more likely to develop allergic reactions to other foods including eggs, soy, and peanuts. Most children with milk allergies also develop one or more other atopic diseases such as asthma, allergic rhinitis, or eczema.

Egg Allergies

Egg allergies occur most often in children and usually resolve at a very young age. However some people may remain allergic to eggs for their entire lives. A person may be allergic to a certain protein in either the yolk or the egg whites. A person with an allergy to the egg yolk may be able to tolerate egg whites and vice versa.  Some people are allergic to both.

Peanut Allergies

Children with peanut allergies rarely grow out of their sensitivity to peanuts, so a peanut allergy is usually a lifelong disorder. Because of this, peanut allergies are particularly serious. Accidental exposure can occur at any time during a person's life. Though rare, a peanut allergy may result in anaphylaxis. This is a severe allergic reaction that can restrict breathing or cause cardiac arrest. Anaphylaxis requires immediate medical attention in the form of a shot of epinephrine (EpiPen). A patient should be watched for several hours after the shot to make sure symptoms don’t return.

Other Common Allergies

Less is known about soy and wheat allergies than the more common allergies discussed above. Likewise, little is known about fish, shellfish, and tree nut allergies except that, like a peanut allergy, they are generally lifelong disorders.

Diagnosis

Food allergies are usually diagnosed depending on the severity of symptoms. If a patient's symptoms are mild, a doctor may recommend keeping a food diary to record all of the foods you eat or drink to pinpoint the culprit. Another way to diagnose a mild food allergy is to remove certain foods from the diet and then slowly reintroduce them to find out if symptoms return. In the case of more severe allergies, skin or blood tests can identify egg, milk, nut, and shellfish allergies.

Treatment Options

As with other types of allergies, avoidance is most often the best medicine. Anyone with a food allergy should be careful when purchasing food at a supermarket or restaurant to make sure there are no traces of the allergen in a food or meal.

Milder symptoms may not require any treatment at all, or a simple over-the-counter antihistamine may resolve the symptoms.

For more serious allergic reactions, a doctor may prescribe steroid medications. Steroids may have serious side effects and shouldn't be used for more than a few days at a time.

Allergen Management in food Manufacturing Facilities

If allergens are included in any products within the facility, then an allergen management program must be developed to address potential cross contact by allergens. Each facility is required to compile a current master list of allergens within the production environment. The general listing of accepted allergens includes peanuts, tree nuts, milk, eggs, soybean, shellfish, fish, and wheat. In Canada, sulfites and sesame seeds are also considered allergens. If these are included in any products produced within the facility, then consideration must be made to address cross contact by allergens. Allergens are managed by two possible methods:

Product labeling: Include all potential allergens on the label of all products produced within the facility (“This item may contain…”)

Allergen control: Includes the management of the production schedule to list products with allergens produced prior to sanitation activities.  It also includes the proper cleaning and sanitizing of equipment contacting allergens.

A verification program is needed to insure compliance with allergen control procedures. Facilities having allergens must have a documented allergen rework program. Products that contain rework must also be considered when potential allergenic ingredients are used. Appropriate allergen controls must be applied to the rework as well. Additional controls that should be included in the allergen management program are:

Storage of allergens in dry storage, all allergens need to be segregated from non-allergens and non-like allergens

Ingredient storage, all allergens need to have a dedicated storage bin, and dedicated dispensing utensil and weigh vessel, if applicable.

Documented change over procedures for switching from allergens to non-allergens. This should include a Sanitation Standard Operating Procedure, monitoring to ensure product removal, and verification of the SSOP. Appropriate testing methods should be used to ensure effective allergen removal. A label reconciliation program is established to ensure that all product labels accurately reflect the presence of allergens based on product formulations, and random audits of products with allergens to ensure that the labels are accurate. Facilities under FDA regulation must comply with the US FDA Food Allergen Labeling and Protection Act of 2004.

Application of Hurdle Technology in Food Industry

Modern Foods Industry

The prepared foods industry is in the midst of its third generation of growth. The "first generation" of prepared foods focused on canned foods although many food marketing experts believe that this category has reached its market potential. The "second generation" of prepared foods focused on frozen foods, which demonstrated phenomenal growth during the past two decades, but many experts believe that this category has also reached its maturity. We are currently in the midst of a "third generation" of technological and market innovation defined by value-added refrigerated prepared foods.

Each "generation" of prepared foods has taken considerable time to move through its life cycle—from technological breakthrough, to market entry, to consumer acceptance and finally to commercial success. Typically, this learning phase is followed by rapid growth in the category. The refrigerated prepared foods category is achieving commercial success faster than prior generations of prepared foods, driven by rapid advances in technology and evolving consumer preferences.

Consumer demand for products offering even greater convenience and higher quality has increased dramatically in recent years. "Convenience" is widely recognized as a major purchasing motivator for prepared foods today. In addition, the term "fresh" has been equated with higher quality, better taste, improved nutrition and a positive benefit that consumers demand. "Fresh­ness" and "convenience" are attributes that are inherent in this third generation of refrigerated prepared food products, particularly products that are ready-to-eat and do not require microwave or oven heating prior to consumption. In addition, refrigerated foods offer the promise of premium quality, because they do not undergo the same quality limiting processes that result from canning and frozen food practices, which impact potential food texture, color and flavor.

Pre­cut and prepackaged lettuce, for example, served as the pioneering product of the fresh­cut segment of the refrigerated foods industry and is an outstanding example of the dramatic growth that can be achieved in a very short time. This segment grew from essentially a zero baseline in the mid­1980s to a $15+ billion dollar industry over the past 25 years, and represents the fastest growing segment of the $80+ billion fresh produce industry. The convenience of product use, and the quality and variety offered by prepackaged items, have changed consumer purchasing behavior and created "halo" effects for other prepackaged products such as pre­cut fruits and vegetables.

Refrigerated perishable products offer a unique level of complexity since there is no singular technology or "kill step" to assure product safety for the broad spectrum of products that exist. Unlike canning and freezing technologies, the attributes of quality in a refrigerated food product will vary considerably from the beginning to the end of a product’s shelf life. This variability in quality has been further increased by manufacturers of refrigerated foods in the U.S. as the need for lengthened distribution requirements has necessitated shelf life requirements that are among the longest in the world. A number of food technologies have been aimed at preventing food pathogens from infesting food products. These technologies are identified as "hurdles" or "barriers" and have varying effects on the safety and shelf life of food products. Their level of effectiveness is dependent in part on which technology is used, the degree to which these technologies are applied and whether multiple hurdle and barrier technologies are used. Just as their name implies, "hurdle" technologies can in fact be "overcome" by food pathogens. Nevertheless, deployment of these technologies can make foods increasingly impenetrable by pathogens, based on which ones and how these prophylactic factors are applied. While a bacterial pathogen may overcome a single hurdle, or maybe even two hurdles, the use of multiple hurdles in a food product greatly reduces the probability that a pathogen will overcome them all. To a food marketer and/or manufacturer, integration of a hurdle technology offers tremendous value and may be considered as: 1) a potential critical control point (CCP) in a product’s Hazard Analysis CCP (HACCP) plan, and/or 2) a weapon in an arsenal of technologies that provides for enhanced food safety and/or enhanced food sensory characteristics for a greater period of time and/or 3) a technology that provides a company with a distinctive competitive advantage.

Hurdles are proactively determined, preventative tools designed to minimize microbial and/or sensory degradation, and enhance or extend the potential shelf life of a food product. They are effectively "tools in the toolbox" that can be used by manufacturers of perishable foods and others involved in the product’s refrigerated distribution chain. It is essential that hurdle technologies be used, because we cannot rely exclusively on the maintenance of refrigerated conditions throughout the distribution cycle to assure the safety of perishable foods. In fact, refrigeration alone is not enough to prevent the growth of some infectious or toxigenic microorganisms. Therefore, hurdle technologies and processes must be incorporated into these foods to yield a safe and stable system. Hurdles can be applied in various phases or potentially in all phases of the life cycle of a food product, from field to fork.

Application of Hurdle Technologies from Farm to Fork

Pre-Harvest Agricultural Practices

Microbial loads on fresh produce can vary considerably by product, by degree of maturity, by geographic location, by field and location in the field. Crop plant physiology, morphology, proximity to soil and other conditions in which contamination can occur are significant, as pathogens have been shown to be internalized via roots, flowers, stem scars, pores, channels, bruises, air cells and temperature differentials. In the case of fresh­cut produce products, it is critical to prevent fruits and vegetables from becoming contaminated with pathogens in the first place. The focus of efforts needs to be on prevention, particularly at the farm and packing shed level, because once contaminated, fresh produce cannot be reliably decontaminated by any current technology except heat. For this reason, the focus of industry is on prevention, including good agricultural practices (GAPs) and HACCP programs, implemented at the farm level. GAPs comprise a systematic production protocol that cover all farming steps from seed sowing through the loading of palletized boxes of harvested produce onto trucks. GAPs stress the implementation of measures that promote human and farm animal sanitation and segregation from crops, especially direct contact and management of nearby wastes.

Enforcement by a system of third party audits is accomplished to ensure compliance with the terms of the GAPs. However, because there are so many possible routes of contamination on a farm, and because there is a dearth of good research into on-farm food safety, there is no general agreement as to what GAPs should encompass and how they should be applied. Consequently, many versions of GAPs have evolved, and in-house and third-party auditing practices are not standardized, creating further industry confusion. In such an environment, it is quite difficult to differentiate the food safety programs of one supplier against another.

• As in any HACCP program, there must be a continuous chain of prevention throughout all of the steps involved in the growing and harvesting process.
• Pathogens can contaminate produce via adulterated water from irrigation, spray water or runoff from areas grazed by animals;
• by fecal contamination of soils due to grazing animals, human waste or uncomposted manure used as fertilizer;
• by infected workers who practice poor personal hygiene; and
• by contamination that occurs in processing from hydro-cooling, wash water and pathogen harborage that may occur on product contact surfaces and in the environment.

Post-Harvest Agricultural Practices

The efficacy of sanitizers in mitigating human pathogenic microorganisms on a wide range of whole and fresh-cut fruits and vegetables has been studied extensively. Numerous challenge studies to determine the effects of storage conditions on survival and growth of pathogens on raw produce have also been reported. Although there are a number of sanitation treatments for fresh-cut produce in use today, once fruits and vegetables have been contaminated with bacterial pathogens or parasites, only thorough cooking will eliminate these organisms, although heating will not necessarily remove microbial toxins. It has been demonstrated that pathogens can be internalized into the produce. Therefore, it is possible to reduce the numbers of pathogens on produce by washing in a sanitary solution, but it is not possible to eliminate them. Furthermore, biofilms have been demonstrated to protect pathogens against bactericidal agents used in postharvest sanitation. Even abrasive scrubbing in a sanitary solution can only reduce, but not eliminate, bacterial counts.

U.S. Food and Drug Administration (FDA) guidance documents indicate that a series of washes may be more effective than a single wash. An initial wash treatment may be used to remove the bulk of field soil from produce, followed by an additional wash or washes containing an antimicrobial agent. Vigorous washing of produce (so long as it is not easily bruised or injured) will increase the likelihood of pathogen removal. Furthermore, different methods may be used to wash different types of produce, including submersion, pressurized spray or both. Regardless of the method used, however, maintaining the quality of the wash water is important to minimize the potential for contamination, and maintaining its effectiveness is a CCP as well. Wash water must also be applied at the appropriate temperature, as produce is susceptible to infiltration of wash water if warm produce is placed in water that is cooler than the produce. This temperature difference creates a pressure differential causing air spaces inside the fruit or vegetable to contract, thereby allowing water to be pulled into the fruit or vegetable.

Because water based sanitizers can only kill those bacteria that they contact, and because microorganisms can quickly become internalized or lodged in hydrophobic niches on produce, the best sanitizers can only achieve a 1—3 log (10­ to 1000­fold) reduction of microorganisms. This limitation makes wash water sanitizers an unreliable method for removing and killing pathogens on fresh produce. In fact, a primary function of wash water sanitizers in the produce industry is to prevent the water from becoming a vector for cross contamination. If a single contaminated fruit or vegetable is introduced into wash water, the contaminating pathogen can spread into the water and contaminate any produce that is subsequently introduced into that water. Maintaining sufficient sanitizer activity in the water prevents the spread of microbial contaminants, but it does not reliably disinfect fruits or vegetables that are already contaminated.

Good manufacturing practices are certainly required in the postharvest processing of produce. Ideally this includes a segregated area for sanitizing produce, the creation of "low risk" and "high risk" processing operations and the utilization of "cleanroom" practices that will be described in the following section. Furthermore, slicing and dicing and other food contact equipment needs to be effectively sanitized and monitored as it can be a source of cross contamination.

Product Formulation Procedures

As a product is being formulated at the manufacturing level, a number of natural or synthetic barriers can be introduced that can significantly extend shelf life and provide greater assurance of product safety. Some of these formulation hurdles are defined by the United States Department of Agriculture (USDA) and FDA as "food additives," while others involve modifications to the intrinsic properties of the food itself.

Processing Procedures

The USDA Food Safety and Inspection Service (FSIS) and FDA provide directives to verify the adequate cooking of meat, poultry and other products to ensure a safe process. These directives follow a time and temperature matrix that is destructive to pathogenic organisms. However, in following these guidelines, product can be processed either before or after it has been packaged, and the processing means can either use thermal or non-thermal processing technologies.

Packaging Procedures

In addition to playing a critical role in "communicating" quality in refrigerated prepared foods, packaging clearly plays a critical functional role as well. A few decades ago, equipment and packaging materials designed for refrigerated foods were extremely limited. The growth of the refrigerated food industry would not have been possible were it not for advances that occurred in the packaging industry. Packaging plays a unique role in the case of fresh-cut produce, due to the obvious fact that produce is living, respiring tissue. Harvested produce takes in oxygen, and releases carbon dioxide, water, heat and metabolites. The rate at which these processes occur is known as the respiration rate. Packaging plays a unique role by matching the respiration rate of the product with the gas transmission rates of the packaging material. This is critical to achieve an appropriate balance of gases in the package. As a result, a wide variety of packaging materials is used today, and the concept of "one film fits all" is clearly not applicable in the refrigerated foods industry.

Depending on the product, and on the approach that is used to provide for safety and shelf life, the packaging phase may occur before or after the thermal or non-thermal processing steps. One, some or all of these packaging hurdle technologies can be employed to improve product quality and/or safety.

Modified Atmosphere Packaging (MAP)

Modified atmosphere packaging, in which product is packaged in an atmosphere that is different from that of air, which normally contains about 78% nitrogen, 21% oxygen and 1% percent of other components including carbon dioxide. MAP helps to delay the onset of product degradation, typically by reducing the amount of oxygen exposed to the product during its shelf life. In high-moisture products, such as cooked entrees and fresh-cut produce, MAP may delay microbial and sensory spoilage, reduce browning, slow respiration rate and lower ethylene production. In high-fat products, MAP delays rancidity and preserves the smell, taste, texture and appearance. MAP also helps to delay staling in bakery products. Elevated carbon dioxide above about 10% selectively inhibits the growth of Gram-negative bacteria, such as pseudomonads and other related psychrotrophs, which otherwise grow rapidly and produce off-odors and off-flavors. Elevated carbon dioxide is not effective in preventing the growth of most human pathogens such as Listeria, E. coli or Salmonella. In addition, because resultant oxygen levels can be extremely low, and product can be held for an elongated period of time, an atmosphere that is conducive to growth of anaerobic bacteria, such as Clostridium botulinum, may evolve. Therefore, competing organisms and/or incorporation of other barriers and/or the testing of product via challenge studies will minimize such risks. Vacuum packaging and vacuum-skin packaging are other forms of modified atmosphere packaging in which the overall quality and safety objectives are the same. However, a different and potentially more aesthetically pleasing product may result.

Packaging in a "high care" or “cleanroom” environment in which product should flow in one direction from raw material receipt, to raw material preparation, to processing, to packaging and air pressure should be positive to the outside. Typically, this environment will utilize this positive air pressure and also high-efficiency particulate air (HEPA) filters that are over 99.97% effective for particles one micron or greater. Makeup air is one of the central issues in maintaining clean airflow in the processing plant and this can be quantitatively measured. There are also products on the market that are much less expensive, and purify the area utilizing UV and/or ozone base air cleansing systems.

Barrier or respiration enabling packaging materials in which materials are used to minimize or maximize transmission of light, oxygen, carbon dioxide, moisture, fog, etc. Some of these materials may even allow the incorporation of antimicrobial compounds. Micro-perforation is a technology that can be used with high-respiring, fresh-cut produce where high gas transmission rates are needed. Innovations in film resin formulation, extrusion methods and post-extrusion modifications, such as lamination and perforation, are constantly being developed.

Active packaging systems that involve an interaction between the packaging used and the food may include a visible or invisible packaging additive. The intent is to extend the shelf life and quality of foods while simultaneously insuring product safety. Methods may enable, for example, oxygen scavenging, carbon dioxide production, moisture/relative humidity control, ethylene control, ethanol release, odor removal or venting and steam release microwaveable packaging.

Intelligent packaging systems utilize a sensor to provide information about the product to the consumer, food service operator or other user. The most widely known intelligent packaging system is the time temperature indicator, which uses a visual indicator to correlate with the acceptable quality, or lack thereof, of perishable foods. These indicators use physical, enzymatic or chemical reactions that correlate to the time temperature degradation of the product. Other indicators that have been commercialized or are in the research phase include ripening, spoilage and pathogen indicators. In the future, radio frequency identification (RFID) technology may enable the incorporation of such quality measures.

Temperature Control, Cold Chain Management and Distribution

Temperature control is the most important, and perhaps the most obvious, intervention for assuring product safety and maximizing shelf life potential in refrigerated value added prepared foods. The effects of temperature are, however, frequently misunderstood and overlooked. The temperatures encountered at each link of the food distribution chain have a direct bearing on the shelf life, quality and potential safety of all perishable food products.

Distribution, including all operations that occur from the manufacturing plant to the retail/foodservice operator and ultimately to the consumer’s home refrigerator, has frequently been regarded as the "Achilles heel" in cold chain management. The distribution system has, in fact, been attributed by many to be a major limiting impediment to the potential growth of the entire refrigerated foods category. Despite the standards and information provided by federal, state and county agencies, training efforts have been deficient, and various surveys have shown that temperatures of foods in U.S. chilled food distribution channels are frequently in the range of 40—55 °F, which is simply unacceptable. Stringent temperature controls need to be implemented at each link of the chain. As the cold chain is "only as strong as its weakest link," one can easily recognize the potential for temperature abuse to occur during the distribution process, and see how a single event in this chain can be a contributing factor for a foodborne illness.

The design and functionality of the retail case itself has a major impact on product shelf life. Studies have shown that the refrigerated cabinets in the produce section of the store, for example, maintain some of the warmest temperatures of any refrigerated cases in the entire supermarket; even though products sold there are among the most susceptible to spoilage and foodborne disease outbreak. Built into most systems are defrost cycles, lights, ballast, etc. that impair their effectiveness, and air curtains that are easily disturbed during normal operation. Proper circulation of cooling air is essential if temperature control is to be maintained.

"Super-chilling," also called "sub­zero degree chill," "deep chilling" and "super-cooling," is generally agreed to be the temperature from about 28—34 °F (­2 °C to +1 °C), which is just above the freezing point of the product or raw material. As products freeze at different temperatures, the suggested storage temperature of 29—33 °F (or 31 °F ± 2 °F), will be acceptable for most perishable products. The USDA has specifically defined the freezing temperature of poultry, for example, at the slightly colder temperature of 26 °F (­3.3 °C). Below 26 °F, the USDA indicates that raw poultry products become firm to the touch because much of the free water is changing to ice. At 26 °F, however, the product surface is still pliable and yields to the thumb when pressed. The USDA has determined that most consumers will consider a product to be fresh, as opposed to frozen, when it is pliable and is not hard to the touch.

It has been scientifically determined that at these deep chill temperatures most microbiological activities are minimal. When temperatures are continuously maintained in this range, shelf life can be extended by at least 50% compared with storage at conventional refrigeration temperatures of 39—50 °F (4—10 °C). Super-chill temperatures result in greatly slowed chemical and biochemical processes and therefore, provides for improved product quality in almost all cases.

The inhibition of growth of a majority of pathogenic and food spoilage microorganisms is an extremely important advantage with super-chilling. The effect of low temperatures on different microorganisms is well documented in the literature. In the interval between 2°C and just above the freezing point of a food, practically all pathogenic bacteria have lost their ability to form toxins, and the growth rates are significantly reduced, but in some cases not completely stopped. Listeria monocytogenes, for example, has been shown to still grow at these super-chill temperatures. However, even its growth rate is reduced when compared to more typical storage conditions.

Temperature recording devices are valuable tools, and should certainly be incorporated into each stage of the cold chain as part of an overall HACCP plan. Many such indicators exist. New systems are now available that utilize wireless sensors and sophisticated web based tracking capabilities, providing a quicker ability for monitoring and alerting should a problem occur.

Application of Barrier Technology and Hurdle Technology in Food Preservation and Food Safety

Food Preservation

Food preservation in the broad sense of the term refers to all measures taken against any spoilage of food. In its narrower sense, however, food preservation connotes processes directed against food spoilage due to microbial or biochemical action. Preservation technologies are based mainly on the inactivation of microorganisms or on the delay or prevention of microbial growth. Consequently they must operate through those factors that most effectively influence the survival and growth of microorganisms (ICMSF, 1980).  Factors used for food preservation are called ‘hurdles’ and there are numerous hurdles that have been applied for food preservation. Potential hurdles for use in the preservation of foods can be divided into physical, physicochemical, microbially derived and miscellaneous hurdles (Leistner and Gorris, 1995). Among these hurdles, the most important have been used for centuries and are as either ‘process’ or ‘additive’ hurdles including high temperature, low temperature, water activity , acidity, redox potential (Eh), competitive microorganisms (e.g. lactic acid bacteria) and preservatives (e.g. nitrite, sorbate, sulphite). Recently the underlying principles of these traditional methods have been defined and effective limits of these factors for microbial growth, survival, and death have been established. Recently, about 50 additional hurdles have been used in food preservation. These hurdles include: ultrahigh pressure, mano-thermo-sonication, photodynamic inactivation, modified atmosphere packaging of both non-respiring and respiring products, edible coatings, ethanol, Maillard reaction products and bacteriocins.

Barrier Technology

To control food safety, providing barriers to food contamination is a generally applied concept. The first barrier refers to outside premises, such as fencing, to prevent unauthorized access to the facility. The access of transport vehicles with raw materials and end-products, personnel, domestic and non-domestic animals should be monitored and controlled. Factory site drainage and storm water collection must be sufficient; areas within a 3-m perimeter of the factory must be kept vegetation free to avoid pest breeding and harborage sites; a 10-cm thick concrete curtain wall around the factory foundation at least 60 cm below ground discourages rodents from entering the building; effluent treatment plants and waste disposal units should be sited such that prevailing winds do not blow microbial and dust aerosols into manufacturing areas.

The second barrier concerns the closing of factory buildings. All entrances/exits (i.e., window and door openings, openings for vents, air circulation lines, floor drains, etc.) must be designed for control over access, flow or exit of personnel, raw and finished food products, air, process aids (process water, process steam, food gases, etc.), waste, utilities (plant cooling and heating water, plant steam, compressed air, electricity, etc.) and pests (insects, birds, rodents, etc.). Floor drains must be screened to avoid rats from entering the food plant via sewers; ventilator openings, including vents in the roof, should be screened to prevent the entry of roof rats, insects and birds; gaps at the entrances of electrical conduits, process and utility piping, which are convenient pathways for roof rats, must be closed.

The third barrier is the segregation of restricted areas (zones) within the plant, each of which has different hygienic requirements and controlled access. The fourth barrier is the processing equipment (including storage and conveying systems), which must have an adequate hygienic design and must be closed to protect the food product from external contamination. When the external contaminations have been eliminated, it is quit easier to handle internal contaminations as well as other sources of food spoiling while processing or after processing. Use of integrated preservation methods instead of using single preservation method to keep food fresh and nourished is a well-known fact, where it can further reduce the production cost as well as rigorous processing methods that’s where Hurdle Technology come to play a major role.

Hurdle Technology

Hurdle technology was developed several years ago as a new concept for the production of safe, stable, nutritious, tasty and economical foods. It advocates the intelligent use of combinations of different preservation factors or techniques ('hurdles') in order to achieve multi-target, mild but reliable preservation effects. Attractive applications have been identified in many food areas. The microbial stability and safety of most traditional and novel foods is based on a combination of several factors (hurdles), which should not be overcome by the microorganisms present. This is illustrated by the so-called hurdle effect. The hurdle effect is of fundamental importance for the preservation of foods, since the hurdles in a stable product control microbial spoilage, food-poisoning and, in some instances, the desired fermentation process. Hurdle technology is a method of ensuring that pathogens in food products can be eliminated or controlled. This means the food products will be safe for consumption, and their shelf life will be extended. Hurdle technology usually works by combining more than one approach. These approaches can be thought of as "hurdles" the pathogen has to overcome if it is to remain active in the food. The right combination of hurdles can ensure all pathogens are eliminated or rendered harmless in the final product.

Hurdle technology has been defined by Leistner (2000) as an intelligent combination of hurdles which secures the microbial safety and stability as well as the organoleptic and nutritional quality and the economic viability of food products. The organoleptic quality of the food refers to its sensory properties that are its look, taste, smell and texture. The hurdle concept illustrates only the well-known fact that complex interactions of temperature, water activity, pH, redox potential, etc. are significant for the microbial stability of foods. Examples of hurdles in a food system are high temperature during processing, low temperature during storage, increasing the acidity, lowering the water activity or redox potential, or the presence of preservatives. According to the type of pathogens and how risky they are, the intensity of the hurdles can be adjusted individually to meet consumer preferences in an economical way, without compromising the safety of the product. Hurdle technology is used in industrialized as well as in developing countries for the gentle but effective preservation of foods.

Previously hurdle technology, i.e., a combination of preservation methods, was used empirically without much knowledge of the governing principles. Since about 20 years the intelligent application of hurdle technology became more prevalent, because the principles of major preservative factors for foods (e.g., temperature, pH, a_w, E_h, competitive flora), and their interactions, became better known. Recently, the influence of food preservation methods on the physiology and behaviour of microorganisms in foods, i.e. their homeostasis, metabolic exhaustion, stress reactions, are taken into account, and the novel concept of multi-target food preservation emerged. In the present contribution a brief introduction is given on the potential hurdles for foods, the hurdle effect, and the hurdle technology. However, emphasis is placed on the homeostasis, metabolic exhaustion, and stress reactions of microorganisms related to hurdle technology, and the prospects of the future goal of a multi-target preservation of foods.

There can be significant synergistic effects between hurdles. For example, gram-positive bacteria include some of the more important spoilage bacteria, such as Clostridium, Bacillus and Listeria. A synergistic enhancement occurs if nisin is used against these bacteria in combination with antioxidants, organic acids or other antimicrobials. Combining antimicrobial hurdles in an intelligent way means other hurdles can be reduced, yet the resulting food can have superior sensory qualities.

ISO 22000: Getting Prepared for an Audit

What is an External Audit?

Can you imagine your collage days, when you were waiting for an exam? Now imagine you’re a student who is aware of a major exam scheduled for the end of the month. Instead of studying throughout the week leading up to the exam, you decide to cram the studying into the final 24 hours prior to the exam. You might be thinking to yourself, “That leaves far too much to chance; what if there isn't enough time to cover a certain concept in-depth, or to ensure a full understanding of the subject on the whole?” Those are the same concerns that come along with preparing for a third-party food safety audit. If a food safety manager leaves preparation for the last few weeks leading up to a food safety audit, it will most certainly affect for his or her food safety audit score. Because business success hinges on an outstanding audit score, it’s easy to understand the dangerous consequences when lack of audit-readiness can bring. Third-party auditors use relevant standards such as ISO 22000, BRC, FSSC 22000, HACCP or any other standard to ensure facilities are compliant with the criteria of the concerning standard which means your facility needs to meet or exceed audit standards every time.

With the changes from recent legislation and the numerous, occasionally competing, food safety standards in place, it can be daunting to know how to prepare for a food safety audit. ISO, FDA, USDA, GMPs, GFS I, HACCP, SQF, BRC, FSSC, IFS—the alphabet soup of shifting management programs and agency oversight—are enough to alarm even experienced quality assurance professionals. Though different standards can measure various aspects of the manufacturing and distribution process in different ways, each is designed to improve food safety by reporting and measuring controls and activities such as cleaning, sanitizing and worker hygiene. Depending on the facility and the standard under which it is being audited, specific requirements and their implementation will vary. However, manufacturers who have strong programs in place should think of audits as opportunities to identify how to further improve operations rather than something to be feared.

A Foundation in Good Manufacturing Practices

One overarching theme found in all of the Global Food Safety Initiative (GFS I)-recognized programs are suitability and cleanability to help assure the floors, walls, ceilings, equipment and personnel do not pose a potential risk to the food being produced. These food safety basics are not new; in many ways, they parallel to the requirements published in the Code of Federal Regulations and apply to food manufacturing facilities regardless of whether they fall under regulation by the U.S. Department of Agriculture (USDA) or the U.S. Food and Drug Administration (FDA). Industry-created standards, such as the GFS I-recognized programs like Safe Quality Food (SQF), British Retail Consortium (BRC), Food Safety System Certification (FSSC) and International Food Standard (IFS), lay out the rules that a manufacturer must follow in order to control the safety and quality of their product. The initial push for implementation and certification against these programs came primarily from the food retail community for their private label products, but in recent years, the push has extended to manufacturers of branded products as well as other players in the food production chain, such as ingredient manufacturers and manufacturers of food packaging materials, which come into direct contact with foods. A manufacturer must first implement the food safety management program and then have it audited and certified by a qualified, external, third party audit firm called a certification body. If the audit is successful, the facility is certified for 1 year.

Certification Audit Preparations

When you have implemented your program and have completed your internal verification of your program. As you prepare for your certification audit, here are some basic tips that can help you:

Review the standards – Think of audits like a test in which all of the answers are provided. The standards by which your facility will be judged are clearly laid out, but it never hurts to review them again to see if any have been updated or changed since the last audit.

Conduct an internal pre-audit – Using a checklist with the latest standards that apply to your operation, schedule a daylong walk through of your facility to observe your processes from start to finish. Have a marked-up copy available for review. Try to look at operations from an outside perspective. Whatever the result of the pre-audit, fix any problems that are noted.

Document – Make sure that logbooks, product labels, date stamps, invoices, customer lists and other documents and records prove that you can recall products quickly. Be sure to download any logs you might need; some can be modified to address recordkeeping requirements for the audit, but make sure they provide the information needed to show the auditor that you are consistently meeting the standard's requirements and your own internal requirements.

The Day of Audit – Facility Audit Agenda

Audit agendas are varying according to the standard, but the normal pattern of events are as follows:

Opening Meeting – Confirm the appointment details; introduce the auditor(s) and auditee contacts, confirm scope and the day’s agenda.

Tour of Operations – Areas toured depend of the type of facility, but might include raw material storage areas, production, finished goods storage, personnel facilities, maintenance, chemical storage, packaging storage and external areas e.g. where dumpsters are located. The auditor might interview some operators.

Food Safety File (paperwork section) – New auditees should have at least three months’ worth of paperwork available (unless a short season crop packing facility i.e. in operation less than three months of the year). Please note that the auditor cannot accept documentary evidence after the audit has ended e.g. if on the audit, a pest control document is missing and the auditee tries to fax it the next day, it cannot be used to alter the score.

HACCP Section (if relevant) – The auditor might look at the HACCP file in the opening meeting in order to orientate him or herself about the site program and CCPs. Auditor will interview CCP operators.

Food Security Section – The auditor will have made notes about physical security aspects when carrying out the tour of the operation. These questions are scored.

Miscellaneous Questions and New Questions – Might be covered at any point in the audit, as the topics arise.

Auditor "Quiet" Time – Time required for the auditor to collate notes before delivering the closing meeting.

Closing Meeting – Discuss findings with the auditee team. Auditors are not able to provide either a final score or pass/fail commentary at the end of the audit due to the high number of questions that are asked in the template and the scoring system that is applied. Auditors however do expedite audit reports very quickly and auditees should contact audit firm if reports have not been received within two weeks after the audit has occurred.

It is imperative that the facility is running product i.e. processing, packing, cooling (whatever functions are usually occurring as on a “normal” day) and that a normal compliment of personnel are on site when the audit occurs in order for the auditor to complete a valid assessment. If the facility is not running and/or there are no production employees or product on site, then the audit will have to be terminated and cancellation charges will be applied or the audit can continue as a pre-assessment audit. Please ensure that auditee personnel are available to follow the facility tour and are well versed in the areas that are being inspected.

Documentation Requirements

New Facility Auditees/First Time Facility Auditees

In operation for more than three consecutive months – Auditee should have at least three months of documentation available for review. If the facility has less than three months of most of their documentation available for review a pre-assessment audit is strongly advised. If the auditee has less than three months of most of their documentation available for review and decides to have a regular audit, they should be aware that they cannot receive full conformance for paperwork questions relating to monitoring and that the down score will be based on the amount of paperwork available.

Short season operation, in operation for less than three consecutive months – Auditee should have at least three months of documentation available for review (this may include last season’s documentation). Where an operation does not have three months of records available (e.g. one month of operation per year) auditee should have at least the previous season’s records available for review. If the auditee has less than three months of most of their documentation available for review and decides to have a regular audit, they should be aware that they may not receive full conformance for paperwork questions relating to monitoring and that the down score will be based on amount of paperwork available.

Management Reviews – There must be two consecutive management review data available for the auditing, basically you can have a management review after you start preparing your facility for a certification against a given food safety standard (i.e. ISO 22000) and when you complete the process of implementing your system and after the internal audit is completed.

Existing Facility Auditees

In operation for more than three consecutive months – Auditee should have at least three months of documentation and documentation at least since the last audit.

Short season operation, in operation for less than three consecutive months – Auditee should have at least three months of documentation and documentation at least since the last audit (which includes the last season). Where an operation does not have three months of records available (e.g. 1 month of operation per year) auditee should have at least the previous season’s records available for review.

Visual versus Verbal Confirmation

Visual confirmation is the default method of auditing, whether on the plant tour or the paperwork section. Scores and comments are assumed to have been visually confirmed unless otherwise stated. Verbal confirmations should be the exception to the rule and if auditing properly, these should be rarely used. If a verbal confirmation is accepted, then the auditor should write this in the comments on the question.