While it is apparent that traditional quality control is unable to eliminate quality problems, a preventive strategy based on a thorough analysis of prevailing conditions is much more likely to provide assurance that objectives of the quality assurance programme are met. This point became very clear in the early days of food production and research for the U.S. space program (Bauman 1992). The amount of testing that had to be done to arrive at a reasonable decision point as to whether a food was acceptable in space travel was extremely high. Apart from the cost, a large part of any batch of food production had to be utilized for testing, leaving only a small portion available for the space flights. The result of these early considerations was the development of the Hazard Analysis Critical Control Point (HACCP) system, which was utilized by the Pillsbury Company's project on food production in the 60ies and exposed to the public during the 1971 National Conference on Food Protection (Anon. 1972).
The HACCP-system was and still is primarily aiming at guaranteeing food safety but can easily be extended to cover spoilage and economic fraud.
Further development and introduction of the HACCP-system into the general food production has been very slow (see Section 5.14). However, in recent years the system has been widely discussed and a number of new quality systems have been introduced, such as certification under an International Accepted Standard (ISO 9000 series) and Total Quality Management (TQM) in which everybody in an organisation is fully committed to achieving all aspects of quality.
One reason for this development is that a number of national food legislations today are placing full responsibility for food quality on the producer (EEC Council Directive 91/493/EEC (EEC 1991b)) and e.g. U.K.'s Food Safety Act (1990) is offering the possibility of a defense of due diligence being offered in prosecutions brought under the Act. This means that a truly documented system of quality assurance can support the plea that the manufacturer has been exercising due diligence. Harrigan (1993) stated that an organization may implement a quality system e.g. introduce HACCP, TQM or become certified under ISO 9001/2 for the following reasons:
To improve the efficiency and profitability of their operations and the quality of their products.
To satisfy a requirement from their customers/purchasers.
To provide a due diligence defense in legal actions.
To keep up with their competitors.
The advantage of having a documented, formal procedure for food quality assurance is now widely recognized. In the European Community (EC) a proposal for a Council Directive on the hygiene of foodstuff (EEC 1992) recognizes and requires the use of HACCP by food business operators while the application of standards of the EN 29000 series is recommended.
After the basic principles of the system were published in 1971 (Anon. 1972) it has now been further elaborated by the ICMSF in publications for the World Health Organization (WHO) and finally in a book (ICMSF 1988). The HACCP-system has been widely discussed and unfortunately a number of new definitions and approaches have been published. This situation is likely to create some confusion and misunderstandings, unless some international agreements can be reached. A working group of the Codex Alimentarius Commission on Food Hygiene is presently (1992) drafting a report on HACCP, which hopefully will clarify these matters. However, the present publication will adhere very closely to the ICMSF definitions and strategy as outlined (ICMSF 1988). The system is based on the recognition that (microbiological) hazards exist at various points, but measures can be taken to control these hazards. The anticipation of hazards and the identification of control points are therefore key elements in HACCP. The system offers a rational and logical approach to control (microbiological) food hazards and avoid the many weaknesses inherent in the inspectional approach. Once established, the main effort of the quality assurance will be directed towards the Critical Control Points (CCPs) and away from endless final product testing. This will assure a much higher degree of safety - at less cost.
The main elements of the HACCP-system are:
Identify potential hazards. Assess the risk (likelihood) of occurrence.
Determine the Critical Control Points (CCPs) Determine steps that can be controlled to eliminate or minimize the hazards.
Establish the criteria (tolerances, target level) that must be met to ensure that CCP is under control.
Establish a monitoring system.
Establish the corrective action when CCP is not under control.
Establish procedures for verification.
Establish documentation and record keeping.
Hazards have been defined (ICMSF 1988) as the unacceptable contamination, growth or survival of bacteria in food that may affect food safety or quality (spoilage) or the unacceptable production or persistence in foods of substances such as toxins, enzymes or products of microbial metabolism. The U.S. National Advisory Committee on Microbiological Criteria for Foods (NACMCF 1992) have defined a hazard as: a biological, chemical or physical property that may cause a food to be unsafe for consumption (NACMCF 1992). For inclusion on the list, hazards must be of a nature such that their elimination or reduction to acceptable levels is essential to the production of safe food. (Some food companies also include regulatory compliance, nutritional value and other important aspects in the definition of hazards). Hazards which are of low risk and not likely to occur would not require further considerations (NACMCF 1992).
Thus, while the ICMSF includes both safety aspects and quality in the definition of hazards, the US-NACMCF is only including safety. In the present presentation, the HACCP-system will be used to control both safety and all aspects of spoilage of fish products.
Hazard analysis requires two essential ingredients. The first is an appreciation of the pathogenic organisms or any disease agent that could harm the consumer or cause spoilage of the product, and the second is a detailed understanding of how these hazards could arise. Thus the hazard analysis requires thorough microbiological knowledge in combination with epidemiological and technological information.
In order to be meaningful, hazard analysis must be quantitative. This requires an assessment of both severity and risk. Severity means the seriousness of the consequences when a hazard occurs, while risk is an estimate of the probability or likelihood of a hazard occurring. It is only the risk which can be controlled.
According to ICMSF, a CCP may be a location, procedure or processing step at which hazards can be controlled. Two types of CCPs may be identified: CCP-1 that will ensure full control of a hazard and CCP-2 that will minimize but not assure full control. Within the context of HACCP the meaning of “control” at a CCP means to minimize or prevent the risk of one or more hazards by taking specific preventative measures (PM).
According to the currently accepted definition by the US National Advisory Committee on Microbiological Criteria for Foods (NACMCF 1992) a CCP is: a point, step or procedure at which control can be applied and a food safety hazard can be prevented, eliminated or reduced to an acceptable level. (Note: No discrimination between CCP-1 and CCP-2). Thus for every step, location or procedure identified as a CCP, a detailed description of the preventative measures to be taken at that point must be provided. If there are no preventative measures to be taken at a certain point, it is not a CCP.
Thus CCPs should be carefully chosen on the basis of the risk and severity of the hazard to be controlled and the control points should be truly critical. In any operation many control points (CP) could be necessary but not critical due to low risk or low severity of the hazard involved. Some of these control points are there as a result of company rules for good manufacturing practice, product reputation, company policy or aesthetics. Such distinction between Control Points and Critical Control Points is one of the unique aspects of the HACCP-concept, which set priorities on risks and emphasizes operations that offer the greatest potential for control. Thus the HACCP points out what is necessary while further control may be nice.
It is not always easy to determine if a certain processing step is a CCP. A “decision tree” based on the ideas of Mayes (1992) and NACMCF (1992) as shown in Figure 5.1 may help to simplify this task. If an identified hazard has no preventive measure (PM) at a certain step then no CCP exists at that step and the question can be repeated at the next processing step. However, if PMs exist at the step it may or may not be a CCP depending on the step being specifically designed to eliminate the hazard under study.
Examples of CCPs are: A specified heat process, chilling, specific sanitation procedures, prevention of cross-contamination, adjustment of food to a given pH or NaCl content.
To be effective, a detailed description of all CCPs is necessary. This includes determination of criteria and specified limits or characteristics of a physical (for example, time or temperature conditions), chemical (for example minimum NaCl concentration) or biological (sensory) nature which ensure that a product is safe and of acceptable quality. Establishment of safe criteria for utilizing a processing step (for example a heat treatment) as a CCP-1 for specified pathogens may necessitate extensive research work before implementation of the HACCP-system. Establishment of microbiological criteria (guidelines or reference values) at various processing steps or the final product also needs extensive investigation such as challenge studies or predictive modelling can be usefully applied when proper verified models are available (see also Section 4.3). Thus, a well equipped laboratory is needed for this purpose.
Other criteria such as moisture level, pH,aw, chlorine level may be known from the technical literature. However, it must be emphasized that the HACCP-team must also define the processing conditions for obtaining safe food. Thus it is not sufficient to state that e.g. the internal temperature of a food must reach a certain temperature. The precise operation to obtain this target level using the available equipment must be determined, and the level of tolerance established. As examples: What is the maximum time at ambient temperature before icing, without significant quality loss? - or before any significant formation of histamine?
The monitoring should measure accurately the chosen factors which control a CCP. It should be simple, give a quick result, be able to detect deviations from specifications or criteria (loss of control) and provide this information in time for corrective action to be taken. When it is not possible to monitor a critical limit on a continuous basis, it is necessary to establish that the monitoring interval will be reliable enough to indicate that the hazard is under control. Statistically designed data collection or sampling systems lend themselves to this purpose and frequency of measurements must be based upon the amount of risk that is acceptable to the management. The effectiveness of control should therefore preferably be monitored by visual observations or by chemical and physical testing. Microbiological methods have limitations in a HACCP-system, but they are very valuable as means of establishing and randomly verifying the effectiveness of control at CCPs (challenge tests, random testing, verification of hygiene and sanitation controls).
| Apply HACCP Decision Tree to Each Step (Answer Questions in Sequence) | |||||
|---|---|---|---|---|---|
| Q 1. | Do Preventive Measures exist | ||||
| YES | NO | Modify step, process or product. | |||
| Is control of this step necessary for safety? | YES | ||||
| NO | NOT A CCP | STOP | |||
| Q 2. | Is the step specifically designed to eliminate or reduce the likely occurrence of a hazard to an acceptable level? | ||||
| NO | YES | ||||
| Q 3. | Does contamination with identified hazard(s) occur in excess of acceptable level(s) or could these increase to unacceptable level(s)? | ||||
| YES | NO | NOT A CCP | STOP | ||
| Q 4. | Will a subsequent step eliminate identified hazard(s) or reduce likely occurrence to an acceptable level? | ||||
| YES | NO | ||||
| NOT A CCP | |||||
| STOP | CRITICAL CONTROL POINT | ||||
Figure. 5.1. Decision tree to locate the Critical Control Points in a process flow (Mayes 1992, NACMCF 1992).
Record keeping and trend analysis constitute integral parts of monitoring as well as a reporting system. Monitoring records must be made available for review by regulatory authorities. All records must be signed by a designated person responsible for the quality aspects.
Since monitoring is a data collection activity, it is important to understand how to collect data. In general, there are ten steps to follow in designing a data collection (monitoring) activity (Hudak-Roos and Garrett 1992):
Ask the right questions. The questions must relate to the specific information needed. Otherwise, it is very easy to collect data that are incomplete or answer the wrong questions.
Conduct appropriate data analysis. What analysis must be done to get from raw data collection to a comparison with the critical limit?
Define “where” to collect.
Select an unbiased collector.
Understand the needs of the data collector, including special environment requirements, training, and experience.
Design simple but effective data collection forms. Remember “KISS” - keep it simple, stupid! Check to see that the forms are self-explanatory, record all appropriate data, and reduce opportunity for error.
Prepare instructions.
Test the forms and instructions and revise as necessary.
Train data collectors.
Audit the collection process and validate the results. Management should sign all data forms after review.
E. Corrective actions
The system must allow for corrective action to be taken immediately when the monitoring results indicate that a particular CCP is not under control. Action must be taken before deviation leads to a safety hazard. According to Tompkin (1992), corrective action involves four activities:
Use the results of monitoring to adjust the process to maintain control.
If control is lost, you must deal with non-compliance products.
You must fix or correct the cause of non-compliance.
Maintain records of the corrective actions.
It is important that one person is designated the responsibility to adjust the process and to inform others of what has happened. Tompkin (1992) also lists five options for dealing with non-compliance products:
Release the product (not the wisest option if safety is involved).
Test the product.
Divert product to safe use.
Reprocess the product.
Destroy the product.
F. Verification
This is the use of supplementary information to check whether the HACCP system is working. Random sampling and analysis can be used. Other examples are the use of incubation tests for sterile or aseptically produced products, tests to see whether products can meet the expected and stated shelf-life and end product examinations. While frequent verifications using traditional microbiological methods may be applied, when the HACCP-system is first implemented, it can be reduced or even abolished when more experience is gained. Verifications could also be carried out by outside parties (government authorities, trade partners, consumer organizations, see also Section 5.1.4).
G. Establish record keeping and documentation
The approved HACCP-Plan and associated records must be on file. Documentation of HACCP procedures at all steps is essential. It should be clear at all times who is responsible for keeping the records. All documentation and records should be assembled in a manual and available for inspection by regulatory agencies.
The principles of HACCP are all very logical, simple and straight forward. However, in the practical application a number of problems are likely to arise, particularly in large food factories. It is advisable therefore to adapt a logical and step-wise sequence for introduction of the HACCP-system as suggested by a HACCP-working group set up by the Codex Alimentarius, Food Hygiene Committee (Pierson and Corlett Jr. 1992), the International Association of Milk, Food and Environmental Sanitarians (IAMFES 1991), Mayes (1992) and Varnam and Evans (1991) as outlined below.
The first step is to ensure that top-management is firmly committed to introduce the system. Many departments and different personnel from chief to line operators will be involved and responsible for part of the system and their full support and cooperation will be essential. However, it is essential that one person (chief of quality assurance) is taking responsibility for the general and overall operation of the system.
Also sufficient resources (personnel, equipment) must be made available for implementation of HACCP.
Introduction of a HACCP-system in large food factories is a complex process and requires a multidisciplinary approach by a team of specialists. The microbiologist is of paramount importance, and must advise the team on all matters related to microbiology, safety and risks. He must have an updated knowledge on these matters and also access to technical literature on the most recent developments in his field. In many cases, he will also need access to the use of a well-equipped laboratory if specific questions and problems cannot be solved by studying the technical literature. Examples are investigations of the microbial ecology of specific products, challenge tests and inoculation studies for evaluation of safety aspects.
Another important member of the HACCP-team is the processing specialist. He must advise on production procedures and constraints, prepare the initial process-flow diagram, advise on technological objectives at various points in the process and on technical limitations of equipment.
Other technical specialists such as a chemist, quality assurance manager, the engineer as well as packaging technologists, sales staff, training and personnel managers can provide valuable information to the HACCP-team and they should attend some of the meetings.
Key-members of the HACCP-team (including the chairman) must have an intimate knowledge of the HACCP-system. Small and medium size industries are not likely to have qualified personnel on the payroll and must therefore buy assistance from outside consultants in order to implement the system.
When the HACCP-team is assembled, their terms of reference must be clearly defined and agreed to by the group. The work may be subdivided into a series of studies, each study dealing with a specific hazard (e.g. C. botulinum as a potential hazard in cold smoked salmon) or production of a specific product including all hazards related to this particular product. Whatever is decided, it should always be clear that the HACCP-system is unique and specific to each processing unit. The HACCP-concept is general but the application is specific to each and every local situation.
A detailed description and specification of the product must be provided to the team at this stage. The specification must include all technological aspects including preservative parameters (NaCl, pH, use of organic acids, other preservatives), intended storage temperature, packaging technology and-most important-intended use of the product. The intended processing technology ingredients list, a precise process flow diagram, description of cleaning and sanitation procedures must also be provided.
A visit to the processing site for verification and to fully understand the process-flow diagram may be made at this stage. Also the facility and equipment designs must be inspected to obtain information on the possibility of additional hazards related to these aspects (i.e. layout, traffic patterns for people, equipment properly sized for the volume of food to be processed etc.).
When all the information regarding product and process has been collected, the data must be analyzed, all hazards identified and Critical Control Points (CCPs) established (HACCP elements A and B). To help in this process, a decision tree as shown in Figure 5.1 can be very helpful. Each step in the process must be analyzed separately and thoroughly, and the main questions must be asked and answered. This involves a discussion not only on the processing steps, but also on the intermediate stages between processing operations. As an example the time-temperature conditions during necessary holding periods can be mentioned.
The level of concern must be assessed at each processing step. This is to ensure that most efforts are directed towards the most critical areas. This level of concern can be assessed in various ways, but in most cases an expert judgement of risk based empirically on available data is sufficient. If this is not possible, tests or investigations may have to be carried out.
All true CCPs must be identified on the flow diagram. If other control points, which are not critical also are marked on the flow diagram, a clear distinction must be made.
Each CCP must have a clear and specific control procedure which specifies how the CCP will be controlled. The preventive measure must be described in detail and target values and acceptable degree of latitude (if any) must be specified as well as when and how control measurements must be carried out (HACCP element C). In Table 5.1 some examples of control procedures are demonstrated.
Equipment and instruments used in control functions must also be kept under strict control, and their performance must be validated regularly.
| Example of Hazard | Critical Control Point | Control procedures |
|---|---|---|
| Growth of C. botulinum | Salting of salmon to be smoked | Required salt level: 3-3, 5% NaCl in water phase of fish Samples for testing from every batch |
| Contamination Contamination | Chlorination of coo- ling water | Continuous chlorine monitor, daily sampling of water for testing. Limit: 5 ppm, tolerance 3–5 ppm. |
| Factory hygiene | Specification of cleaning and sanitation procedures. Visual control before work start. Twice weekly microbiological controls of cleaned surfaces in contact with food. Limit <100 cfu cm-2. Tolerance: Mean <100 cfu cm-2. Max. 103 cfu. | |
| Survival of pathogens | Cooking | Define and ensure time/temperature requirements. Continuous and automatic recording of water temperature |
Monitoring and data recording are essential elements of the system. All actions, observations and measurements must be recorded for possible later use. These records are the tools by which management and outside inspectors are able to ensure that all operations are within specifications and that all CCPs are under full control. A high level of documentation preferably confirmed by the signature of the controller - is also a sign of a high level of control.
Data not directly related to process control should also be recorded. Thus a detailed record of the initial HACCP-study including possible challenge tests or shelf life experiments should also be kept. In addition all changes to product-formulas or processing lines introduced as a result of the HACCP-study must be on record, as well as corrective actions taken when something was out of control.
When the HACCP-study is completed and the programme is ready for implementation, training of staff must take place. All persons involved in the programme from line operators to managers must understand the principles and have a very clear idea of their own role in the system. Training and refresher courses must take place regularly and new staff should not be allowed to begin work before they have gone through training in HACCP principles and procedures.
The initial HACCP-study requires specific expertise in various fields, as well as access to a well equipped laboratory as already stated. In contrast, the daily routines in monitoring the system are quite simple and do not require e.g. expert microbiological skill and little or no laboratory expertise is needed. For small and medium size food companies it is therefore an economical advantage to buy outside expertise to introduce the system - and probably also to carry out the occasional verifications. The expense of installing costly laboratories, employment of highly paid skilled microbiologists - and the running cost of carrying out large numbers of unnecessary end-product analysis can be avoided.
Periodic reviews should be conducted to ensure that the HACCP-system is working correctly and that new developments are taken into account. Keypersonnel as well as line operators should be interviewed to assure that they understand their role in the programme. All changes in product or processing procedures should always be critically assessed before being instituted.
The principles of HACCP-system is equally applicable to large companies with complicated and large varieties of products and processing lines and to small enterprises, with a small production of one or a few simple product types. Naturally, the latter type of processing does not need a large HACCP-team and in-depth studies to introduce the system, as most of the answers are known beforehand. However, the advantage by the system of providing maximum quality assurance in the most cost effective way will also apply equally to both types of processing plants.
The final application of the HACCP-concept in any food processing is unique for every process and for every factory. In each case a detailed study of process flow is necessary in order to identify the hazards and the CCPs. However, some general principles can be outlined. For this purpose, seafood having similar microbiological ecology, handling and processing practice and/or similar culinary preparations before consumption can conveniently be grouped and categorized as shown below.
Seafood hazard categories:
Molluscs, including fresh and frozen mussels, clams, oysters in shell or shucked. Often eaten with no additional cooking.
Fish raw materials, fresh and frozen fish and crustaceans. Usually eaten after cooking.
Lightly preserved fish products (i.e. NaCl < 6% (w/w) in water phase, pH > 5.0). This group includes salted, marinated, cold smoked and gravad fish. Eaten without cooking.
Heat-processed (pasteurized, cooked, hot smoked) fish products and crustaceans (including pre-cooked, breaded fillets). Some products eaten with no additional cooking.
Heat-processed (sterilized, packed in sealed containers). Often eaten with no additional cooking.
Semi-preserved fish (i.e. NaCl > 6% (w/w) in water phase, or pH < 5.0, preservatives (sorbate, benzoate, NO2 may be added). This group includes salted and/or marinated fish and caviar. Eaten without cooking.
Dried, dry-salted and smoke-dried fish. Usually eaten after cooking.
In ranking seafood in risk categories the method of NACMCF (1992) with some modifications has been applied. Thus a number of hazard characteristics are listed as shown below:
There is epidemiological evidence that this type of product has (often) been associated with foodborne disease.
The production process does not include a CCP-1 (i.e. full control) for an identified hazard.
The product is subject to potentially harmful recontamination after processing and before packaging.
There is substantial potential for abusive handling in distribution or in consumer handling that could render the product harmful when consumed.
There is no terminal heat process after packing or when cooked in the home.
The various seafoods can then be assigned to a risk category in terms of health hazards by using a + (plus) to indicate a potential risk related to the hazard characteristics. The number of pluses will then determine the risk category of the seafood concerned as shown in Table 5.2.
| Hazard characteristics | ||||||
|---|---|---|---|---|---|---|
| Seafood products | I | II | III | IV | V | Risk category |
| Bad safety record | No CCP-1 for identified hazard in process | Recontamination between processing and packaging. | Abusive handling during distribution and consumption | No terminal heat process by consumer | ||
| Molluscs (to be eaten raw) | + | + | + | + | + | High1) |
| Fish raw materials Fresh and frozen fish and crustaceans | (+)2) | + | - | - | - | Low |
| Lightly preserved | + | - | + | + | + | High |
| Heat-processed (pasteurized) | + | - | + | + | + | High |
| Heat-processed (sterilized) | (+) | - | (+) | - | + | Low |
| Semi-preserved | (+)3) | - | - | (+) | + | Low |
| Dried, dry salted and smoke dried | - | - | - | (+) | No risk if cooked | |
1) High risk products have 3 or more pluses; Low risk products have less than 3 pluses.
3) Reported outbreak of botulism mostly due to toxin formation in raw material.
The molluscan shellfish are harvested by being raked or trawled from the bottom (oysters, mussels) or dug from the sand at low tide (clams and cookels). After harvesting, the shellfish are sorted (size), washed and packed in bags or crates or just left in a pile on deck. The shellfish may be transported and sold live to the consumer or they may be processed (shucked) raw and by use of heat. The heat applied in processing is only enough to facilitate shucking by causing the animal to relax the adductor muscle, and has no effect on the microbial contamination of the animals. The shucked meat is washed, packed and sold fresh, frozen or further processed and canned.
Most molluscs (oysters, mussels, clams, cockles) grow and are harvested in shallow, near-shore estuarine waters. Thus there is a strong possibility that the live animals may be contaminated with sewage-derived pathogens as well as those from the general environment. Due to the filter feeding of molluscs, a high concentration of disease agents may be present in the animals and therefore constitutes a serious hazard.
Most molluscs are traditionally eaten raw or very lightly cooked. They are therefore obviously a very high risk food, as also confirmed by the epidemiological evidence presented by Garret and Hudak-Roos (1991) who reported that 7% of all outbreaks of seafood-borne diseases (20% of all cases) in the U.S. in the period 1982–87 were caused by molluscan shellfish.
| Hazard | ||||
|---|---|---|---|---|
| Organism/component of concern | Contamination | Growth | Severity | Risk |
| Pathogenic bacteria indigenous | + | +1) | high/low2) | high |
| non-indigenous | + | +1) | high | high |
| Virus | + | - | high/low2) | high |
| Biotoxins | + | - | high/low2) | high |
| Biogenic amines | - | - | - | - |
| Parasites | + | - | low | high |
| Chemicals | + | - | high/low2) | low |
| Spoilage bacteria | + | + | + | high |
1) Growth of bacteria in molluscs after harvesting is only related to dead animals.
2) Severity of illness depends on organism or toxin involved.
Spoilage of dead molluscs is rapid, regardless of being shucked or not. However, the risk of contamination of the meat with specific spoilage bacteria is great during processing and packaging. A summary of hazards in molluscs-processing is shown in Table 5.3.
Unfortunately, it is not possible to control the many high risk hazards associated with consumption of raw molluscs. No CCP-1 can be identified for serious hazards such as contamination of live and dead animals with disease agents. These hazards can be reduced but not eliminated by means of:
Control with the environment of live molluscs.
Factory hygiene, including control of water quality.
This means, that these measures are only of CCP-2 nature.
The hazards related to growth of bacteria in the dead shellfish can be completely controlled by low temperature. Thus time and temperature conditions are CCP-1 for this particular hazard as shown in Table 5.4.
Growing and harvesting of molluscs should be restricted to areas free from direct sources of sewage pollution. This requires knowledge of local geography, prevailing water currents and the local treatment and discharge of sewage. Also monitoring of the microbiological quality of water is required. Thus the current standard for water quality in growing areas in U.S. is 14 MPN fecal coliforms/100 ml water, with no more than 10% of samples exceeding 43 MPN fecal coliforms/100 ml (FDA 1989). However, the value of fecal coliforms as indicator of contamination and possible presence of disease agents have serious limitations as already discussed (Section 4.2).
Also the correlation between presence of indicator bacteria and various disease agents in water and in shellfish has been questioned. The concentration of microorganisms in filter feeding shellfish varies enormously from animal to animal and also depends on weather conditions, temperatures and general activity of the shellfish. For these reasons, there are no microbiological standards for water quality in growing areas specified by the European Economic Community (EEC). Instead, the EEC has placed a microbiological standard (EEC Directive 91/492/EEC) on shellfish for direct consumption (EEC 1991a):
<300 fecal coliforms/100 g meat or
<230E.coli/100 g meat (based on MPN-test)
absence of Salmonella in 25 g meat
PSP < 80μg/100 g edible meat
DSP not to be detected by customary biological testing method
FDA (1989) also specifies a microbiological standard for shellfish as <230 MPN fecal coliform pr. 100 g meat and aerobic plate count (APC) of not more than 500,000/g meat.
| Product flow | Hazard | Preventive measure | Degree of control |
|---|---|---|---|
| Live molluscs | Contaminated1) | Monitoring of environment | CCP-2 |
| Catching | |||
| Chilling | Growth of bacteria | (Txt) control2) | CCP-1 |
| Transport | Growth of bacteria | ||
| Reception at factory | |||
| Shucking | |||
| Packaging | |||
| All processing steps | Growth of bacteria Contamination | (Txt) control Factory hygiene Water quality Sanitation | CCP-1 |
| CCP-2 | |||
| CCP-1 | |||
| CCP-2 | |||
| Chilling | Growth of bacteria | (Txt) control | CCP-1 |
| Distribution | Growth of bacteria | (Txt) control | CCP-1 |
2) (Txt) control = Time x temperature control
It should be noted here that the regulatory agencies in US and Europe have returned to traditional control options (sampling, testing and comparing results with microbiological standards) in an attempt to provide safety in consumption of raw molluscs. As already discussed in Section 4, these methods do not provide any guarantees for safety, and by the application of HACCP-concept it is also clear that noguarantee of safety can be provided. This point should be made clear to consumers, who insist on consumption of raw molluscs. Such warnings are actually used in seafood restaurants in Florida, USA.
Also control of the environment for the presence of toxic dinoflagellates is difficult and facing some of the same types of problems as discussed for bacteria and viruses. The EEC (EEC 1991a) requires periodical (weekly) sampling of water and shellfish from growing and harvesting areas, and in case of elevated presence of toxic algae, the fishing area will be closed. However, analytical techniques is one of the great problems.
An alternate means of securing safety of shellfish is by relaying or depuration and in a number of countries this is required by regulation. Depuration involves placing the shellfish in tanks with clean circulating seawater. Various methods can be used to disinfect the water such as ultra-violet light, chlorine, iodophors, ozone and activated oxygen (Richards 1991) and the shellfish is simply removed from suspect areas to waters which are known to be unpolluted. Both methods are of limited efficiency in the removal of viruses and vibrios from the shellfish (Richards 1991). Efficiency has normally been verified by testing the animals for presence of E. coli. This organism is not suitable as indicator, however, and alternative method is required. Non microbial contamination (toxins/biotoxins, heavy metals, petroleum, hydrocarbons, radionucleides, pesticides) depurate so slowly that commercial depuration is uneconomical (Richards 1991).
In most countries control and monitoring of the environment is the responsibility of the governments and these should be consulted for detailed information. It is expected that governments will ban fishing or harvesting of molluscs, if criteria are not met.
Time-temperature (Txt) conditions at all times from catching to distribution is a CCP-1 in preventing growth of pathogens and spoilage bacteria. Thus the time-lapse between each step in the flow diagram (Table 5.4) must be monitored and similarly the temperature of the environment, chill rooms, factory etc. as well as the temperature of the product must be recorded.
Factory hygiene as well as personal hygiene and sanitation are CCPs in the prevention of contamination of products with microorganisms, filth and any other foreign material during processing. The seriousness (risk) of this hazard varies depending on local conditions (factory lay-out and design, facilities) and intended use of product (cooking or no cooking before being eaten). For this reason, a detailed description of the requirements must be produced in each individual case. These instructions must specify precisely when to clean and sanitize, how to do it, who is responsible, equipment and chemical agents to be used etc. (see also Section 6).
This CCP can then be controlled and monitored by visual inspection of procedures and recording of data in check-lists as shown in the example in Tables 5.7 and 5.8.
Occasionally a microbiological check of cleanliness of surfaces coming into direct contact with exposed meat can be made. Bacteriological control must be regarded more as a verification procedure than monitoring of a CCP. The frequency to carry out this type of check also depends on circumstances. In cases where changes in procedures or personnel has taken place. This control procedure must be carried out on a weekly or maybe on a daily basis. In other cases where routines are well established, microbiological control of cleanliness can be carried out monthly or maybe abolished altogether.
Water quality is a CCP-1 in preventing contamination from this source. Monitoring of this CCP-1 can be carried out by microbiological testing. Where in-plant chlorination is used, chlorine levels must be measured and recorded. Chlorine levels should be measured daily with recommended levels of 2–5 ppm.
The hazard analysis of these products is fairly straightforward and uncomplicated. The live animals are caught in the sea or freshwater, handled and - in most cases - processed without any use of additives or chemical preservatives and finally distributed with chilling or freezing as the only means of preservation. Most fish and crustaceans are cooked before eating although a few countries such as Japan have a tradition for eating raw fish. The epidemiological records show that these products have caused a number of food poisoning outbreaks, but nearly all have been related to the presence of heat stable toxins (biotoxins, histamine).
Live fish and crustaceans and raw products may be contaminated with a number of pathogenic bacteria normally found in the aquatic environment such as C. botulinum, V. parahaemolyticus, various Vibrio sp., L. monocytogenes, Aeromonas sp. However, only the growth of these organisms can be regarded as a hazard, as pathogenicity is related to preformed toxin in the food (C. botulinum) or the minimal infection dose is known to be high (Vibrio). The severity of diseases related to these organisms may be high (botulism, cholera) or low (Aeromonas infections), but the likelihood of provoking diseases (risk) is extremely low. The pathogenic strains require temperatures > 1 ° C for growth and they are competing with the normal spoilage flora whose growth potential is comparatively much higher at low temperatures. Thus the products are likely to be spoiled before production of toxin or development of high numbers of pathogens. When the products are cooked before consumption, this will completely eliminate the risk.
Pathogenic bacteria from the animal/human reservoir (Salmonella, E. coli, Shigella, Staphylococcus aureus) may contaminate the live animal depending on the fishing area and further contamination may take place during landing and processing (Figure 5.2). The diseases which these organisms can provoke are serious, but if numbers on the products are low (i.e. no growth has taken place) the likelihood of this to happen (risk) is very low indeed. Cooking before consumption will eliminate the risk. However, an indirect hazard exists if contaminated products are polluting the working areas (industry, kitchen) and thereby transporting the pathogens to products which are not cooked before eating (cross contamination). This indirect hazard must also be prevented.
In contrast, the effect from growth of histamine producing bacteria (Morganella morganii) will not be eliminated by cooking or any other heat treatment as the heat resistance of histamine is high. The risk of histamine poisoning, if fish (Scombroidae) have been kept for some time at elevated temperatures (> 5 ° C) is therefore high.
Fish caught in certain areas may be infected with parasites dangerous to human health. The severity of the possible disease depends on the parasite involved, and the likelihood of contracting parasites from fish is eliminated if the fish is cooked before consumption. A low risk will exist if fish are consumed raw.
Figure 5.2. Exposure of catches to heavy contaminated coastal waters during landing
The presence of biotoxins and chemicals in fish depends on fish species, fishing area and season. The biotoxins are heat-stable and the risk of intoxication after consumption (raw or cooked) is high. The safety hazards related to fish raw materials for further processing and to consumption of fresh and frozen fish are summarized in Table 5.5.
Heavy contamination and in particular, growth of specific spoilage bacteria is certain to reduce the normal and expected shelf-life of the product (high risk). This may of course cause serious commercial problems but no lives are endangered. Thus, severity is low.
The Critical Control Points in production of fish and frozen fish are marked in Table 5.6.
The contamination of live fish with bacteria normally found in the environment obviously cannot, and need not be controlled (- it is a hazard, but with no risk). However, contamination with bacteria from the animal/human reservoir can be limited by monitoring the fishing areas and control of fishing if gross pollution from population centres or industry is evident. More important, however, is the monitoring of the fishing areas for the presence of parasites, biotoxins (-toxic fish or toxic marine plankton), and toxic chemicals.
| Hazard | ||||
|---|---|---|---|---|
| Organism/component of concern | Contamination | Growth | Severity | Risk |
| Pathogenic bacteria indigenous | - | + | high/low | no risk1) |
| non-indigenous | (+) | + | high | low |
| Virus | (+) | - | - | no risk1) |
| low | ||||
| Biotoxins | + | - | high | high |
| Biogenic amines | - | + | low | high |
| Parasites | + | - | low | no risk2) |
| Chemicals | + | - | low | low |
| Spoilage bacteria | (+) | + | low | high |
1) no risk if product is cooked.
2) no risk if product is cooked or frozen.
Monitoring of the aquatic environment for pollution (fecal) and presence of chemical toxins and biotoxins in fish or algae may in most countries be a responsibility of the government and is most conveniently carried out by specialized laboratories. However, even with the best monitoring of the environment, the risk of toxic fish reaching the consumer can be reduced, but not completely eliminated. Thus, for this particular hazard, only a CCP-2 can be established. The critical limits for biotoxins and pollution are found in national legislations or international recommendations. The most important are quoted in Section 3.
Time and temperature (Txt) conditions at all times (all steps) from catching to distribution is a CCP-1 in preventing growth of pathogenic bacteria, histamine producing bacteria and spoilage bacteria. At t < 1°C, no growth of pathogenic bacteria takes place. Only small and insignificant amounts of histamine may be formed and bacterial spoilage is not inhibited, but taking place at a “normal” and expected rate. A maximum time at t > 5°C (or max. processing time) must be specified in the criteria or tolerances for this CCP.
Time and temperature conditions are also important CCPs in preventing oxidation and chemical spoilage. Thus exposure for a few hours of fatty fish to sun, air and ambient temperature during e.g. catch handling, is sufficient to introduce severe quality loss and cause early chemical spoilage (Figure 5.3).
| Product flow | Hazard | Preventive measure | Degree of control |
|---|---|---|---|
| Live fish | Contaminated1) | Monitoring of environment | CCP-2 |
| Catch and catch handling | Growth of bacteria | (Txt) control | CCP-1 |
| Chilling | Growth of bacteria | (Txt) control | CCP-1 |
| Landing | Excess contamination and/or | Hygienic handling | CP |
| growth of bacteria | (Txt) control | CCP-1 | |
| Arrival of raw material at factory | Substandard quality entering processing | Ensure reliable source | CCP-1 |
| Sensory evaluation | CCP-2 | ||
| Storage of raw material | |||
| Washing | |||
| Filleting | Presence of parasites | Candling | CCP-2 |
| Skinning | |||
| All processing steps | Growth of bacteria Contamination | (Txt) control | CCP-1 |
| Factory hygiene | CP | ||
| Water quality | CCP-1 | ||
| Sanitation | CP | ||
| Packaging | Spoilage (oxidation) | Packaging material/vacuum | CCP-1 |
| Chilling | Growth of bacteria | (Txt) control | CCP-1 |
| Freezing | Chemical/autolytic spoilage | (Txt) control | CCP-2 |
Figure 5.3. Delay in icing chilling on board may cause bacterial growth (histamine formation, spoilage) and chemical spoilage (oxidation).
Monitoring of time/temperature conditions during handling and processing can be done by date marking of boxes and containers and by visual inspection of icing and chilling conditions. Time and temperature recording at specific points and during processing should preferably be controlled automatically. Process flow must be designed to avoid stops and interruptions, and all chill rooms must be supplied with thermometers. Visual inspection (e.g. quantity of ice) and control checks of temperature must be done in a daily routine. Automated time/temperature integrators are also available on the market and can be usefully applied. A log on temperature recordings (manually or automatically read) must be kept and be available at all times.
A sensory assessment (appearance, odour) of the raw material on reception at factory or immediately before processing is a CCP-2 for ensuring that until this point the material has been under control, that spoiled fish or shrimp do not enter the processing area, and that potential toxic species can be discarded.
Adherence to initially established GMP is as well as sanitation and factory hygiene procedures are control points (CP) to reduce or avoid gross contamination and these control measures must be monitored as a daily routine (see Section 5.1.3.A). It should be noted that contamination during processing of raw fish to be eaten as cooked is a hazard with a very low or no risk (Table 5.5). Consequently, hygiene and sanitation in this type of production is not truly a CCP but only a control point (see Section 5.1.1.B for discriminating between CCP and CP).
Packaging and freezing are CCPs for control of chemical and autolytic spoilage. The packaging methods and materials (which are the criteria for this CCP) are normally specified in the sales contract. The freezing method is restricted to available equipment but rapid freezing to t < -18°C and a storage temperature at -18°C are essential criteria for the second CCP.
All observations and measurements must be recorded on checklists and data sheets. Examples are shown in Tables 5.7 and 5.8 (after Hudak-Roos and Garrett 1992).
In conclusion, it can be stated that in the production of fresh and frozen fish and crustaceans most hazards can be controlled in a routine quality assurance programme using very simple equipment and methods. Only the presence of heat stable biotoxins remains a partly uncontrolled hazard.
| SANITATION LOG | ||||
|---|---|---|---|---|
| S=Satisfactory | ||||
| N=Needs Improvement | ||||
| Date:………… | A=Alert | |||
| Prestart | Break 1 | Break 2 | Comments | |
| TIME: | ||||
| Thaw tank cleaned | ||||
| Glaze water changed | ||||
| Belts cleaned and in good repair | ||||
| Utensils cleaned and in goods repair | ||||
| Processing machines cleaned | ||||
| Lighting | ||||
| Floor clean | ||||
| Collings without pooling paint or condensates | ||||
| Dlp stations | ||||
| Trash removed | ||||
| Chlorlne barrels | ||||
| Ins. By:……………Prod.Supu:…………QA Mgr.:………… | ||||
| DATA SHEET | |
|---|---|
| I.T. LINE 1 C.L. -180°F | |
| TIME | TEMPERATURE |
| 0800 | 181 |
| 0830 | 181 |
| 0900 | 180 |
| 0930 | 180 |
| 1000 | 179 |
| 1030 | 179 |
| NOTES: | |
| OPETATOR | DATE |
This group includes fish products with low salt content (<6% NaCl (w/w) in aqueous phase) and low acid content (pH > 5.0). Other preservatives (sorbate, benzoate, NO2, smoke) may or may not be added. The products may be prepared from raw or cooked raw material, but are normally consumed without prior heating. Product examples are salted, marinated and cold smoked fish. These products have a limited shelf life, even at chill storage - and there is ample epidemiological evidence of foodborne diseases being traced to these types of products. Nearly all known bacterial pathogens as well as production of biogenic amines are of concern. Parasites may survive and preformed bacterial toxins as well as biotoxins may remain stable during processing and storage of these products. The hazards related to this type of products are summarized in Table 5.9.
The contamination of lightly preserved fish products with low numbers of potentially pathogenic organisms normally found in the environment may or may not be regarded as a hazard. These organisms are frequently or always found on raw materials used and are as such very difficult or impossible to keep completely away from the final product. It must be emphasized, however, that these pathogens will contaminate the environment in the fish factory and that high numbers then may be found in any niche where the prevailing conditions (temperature, nutrients, etc.) are favourable for growth. Gross contamination of the final products may take place from these niches and the presence of high numbers of these organisms on products to be eaten without cooking is a hazard with a high risk which need a CCP (see also the discussion on control of Listeria in Section 3.1).
| Hazard | ||||
|---|---|---|---|---|
| Organism/component of concern | Contamination | Growth | Severity | Risk |
| Pathogenic bacteria indigenous | (+) | (+) | high/low | high |
| non-indigenous | + | + | high | high |
| Virus | + | - | high/low | high |
| Biotoxins | + | - | high | high |
| Biogenic amines | - | + | low | high |
| Parasites | + | - | low | high |
| Chemicals | + | - | high/low | low |
| Spoilage organisms | (+) | + | low | high |
The CCPs for keeping the contamination of the final product with pathogenic microorganisms including virus at a low level is good factory hygiene. Monitoring of the environment, including the factory environment for these organisms, should be carried out at regular intervals depending on the local situation. GMP and factory hygiene must be specified in detail and monitored routinely (see also Section 5.1.3.A).
In contrast, any growth of pathogenic organisms including producers of biogenic amines, is a hazard of potential high severity and high risk. Thus this hazard must be controlled at all cost and production, distribution and storage are extremely important CCPs where time-temperature conditions must be controlled. For most pathogenic bacteria, the traditional chill storage at +5°C or lower is a CCP-1 but it should be emphasized that some of the pathogens are psychrotrophic in nature. This includes L. monocytogenes and C. botulinum type E which can multiply and produce toxins at temperatures down to +3.2°C. For the latter organism, an additional CCP is recommended. A salt level of at least 3% NaCl (w/w in aqueous phase) should be included in the criteria for production of lightly preserved fish products as this is sufficient to prevent growth and toxin production (Cann and Taylor 1979) at low temperature. The slightly increased risk caused by vacuum-packaging or storage of these products in oxygen free environment is insignificant if two separate CCPs of CCP-1 nature are applied and constantly monitored (temperature and salt content).
The presence of biotoxins and parasites in raw material for production of lightly preserved fish products is clearly a hazard of high or low risk depending on the fishing area and season. No CCP-1 can be identified for these hazards, but the risk from biotoxins can be reduced if the fishing grounds are monitored for the presence of toxic organisms (CCP-2) as discussed in the paragraph on fish raw material. As far as parasites are concerned, a “processing for safety” step (e.g. freezing of raw material) should be included in the process.
Spoilage is prevented by controlling raw material, time and temperature (Txt) conditions during processing and distribution, packaging material (oxygen transmission rate of film) and-method (degree of vacuum).
Table 5.10 summarizes the hazards and preventive measures during processing of cold smoked fish.
| Product flow | Hazard | Preventive measure | Degree of control |
|---|---|---|---|
| Raw material before entering the factory | See Table 5.6 | See Table 5.6 | See Table 5.6 |
| Reception of raw materials | Substandard quality entering processing | Ensure reliable source | CCP-2 |
| Washing | |||
| Filleting | |||
| Salting | Salt content too high or too low (i.e. unacceptable taste or risk of growth and toxin production by C. botulinum respectively) | Visual observations of salting procedures and equipment Measurement of salt content of brine and product | CCP-2 |
| Smoking | |||
| Packaging | Spoilage (oxidation, microbial spoilage) | Visual control of packaging material and method (vacuum) | CCP-1 |
| All processing steps | Growth of bacteria Contamination | (Txt) control | CCP-1 |
| Factory hygiene | CCP-2 | ||
| Water quality | CCP-1 | ||
| Sanitation | CCP-2 | ||
| Chilling | Growth of bacteria | (Txt) control | CCP-1 |
| Distribution | Growth of bacteria | (Txt) control | CCP-1 |
Note: The possible presence of live parasites is not controlled by these control measures. As there is no CCP-1 for this hazard in the normal production process, a period of freezing (-20°C for 24 hours) either of the raw material or of the final product must be included in the processing.
A number of fish products receive a heat treatment during processing. Examples are: pasteurized or cooked and breaded fish fillets, cooked shrimp and crabmeat, cook-chill products and hot smoked fish. After the heat-treatment the various products may pass through further processing steps before being packed and stored/distributed as chilled or frozen products. Some of these products may receive additional heat treatment before consumption (cooked and breaded fillets, cook-chill products) or they may be eaten without further heat-treatment (hot smoked fish, cooked shrimp). Thus it is clear that some of these products are in the high risk category being extremely sensitive to contamination after the heat treatment.
To further illustrate the safety aspects, there is ample epidemiological evidence that this type of product has been the cause of food poisoning due to growth of coagulase-positive Staphylococcus aureus and enteropathogenic organisms among the Enterobacteriaceae and Vibrionaceae. Marine crustaceans, usually shrimp, crab or dishes made from them, accounted for 25 outbreaks of food-borne diseases reported in the United States during the period 1977– 84 (Bryan 1988). Although there has been no recorded case of botulism caused by consumption of cooked shrimp, this possibility should not be overlooked, particularly in view of the variation in the ultimate use of this product.
In the application of the HACCP-system to these types of products, the heat-treatment is a very critical processing step. Hazards identified before this step may or may not be eliminated depending on the degree of heat being applied. Most criteria for heat-treatments have been laid down as a consequence of economical and technological considerations and not for hygienic or public health reasons. Noteworthy exceptions are the U.S.-regulations cited by Pace and Krumbiegel (1973) requiring a heat treatment of 82.2°C for a minimum of 30 min. in the processing of smoked fish with the purpose of killing all C. botulinum type E spores and the German requirement of the coldest part of the fish to be heated to 70°C to kill any nematodes, particularly Anisakis simplex present in the fish (German Fish Ordinance 1988). (Note: heating to 70°C is a gross overkill as 55°C for 1 min. is sufficient to kill nematode larvae - see Section 3.4).
Whenever possible, the heat-treatment should be utilized to eliminate harmful organisms. The criteria (time/temperature requirements) should be based on research demonstrating the lethal effect of the proposed heat-treatment.
Following this principle, any bacterial contamination and growth taking place after the heat-treatment is a serious hazard with a very high risk as shown in Table 5.11. In contrast, there are no hazards related to presence of parasites as there is no risk of recontamination with these components after the heat-treatment. A possible hazard related to presence of biotoxins and chemicals is dealt with under “fish raw materials for further processing” (see Section 5.1.3.B).
The critical control points during processing of heat treated products are therefore:
The heat-treatment - which is a CCP-1 in control of pathogenic bacteria.
GMP and factory hygiene/sanitation, which are CCP-2 in the control of recontamination and possible growth of bacteria after the heat treatment
The water quality - which is a CCP-1 in avoiding any contamination from this source.
As an example, the CCPs in the processing of cooked, peeled and frozen shrimp are shown in Table 5.12.
| Organism/component of concern | Hazard | |||
|---|---|---|---|---|
| Contamination | Growth | Severity | Risk | |
| Pathogenic bacteria | ||||
| indigenous | + | + | high/low | high/no risk1) |
| non-indigenous | + | + | high | high/no risk1) |
| Virus | + | - | high | high/no risk1) |
| Biotoxins | + | - | high | high |
| Biogenic amines | - | + | low | high |
| Parasites | + | - | low | no risk |
| Chemicals | + | - | high/low | low |
1) there is no risk if products are cooked again immediately before consumption.
The criteria and the critical limits to be used in monitoring the CCPs are important and must be specified in detail. Thus the heating conditions (water temperature, belt speed etc.) necessary to obtain the desired result (e.g. minimal internal temperature of 80°C for 2 min.) must be determined by experimentation. Similarly the requirements to GMP, factory hygiene and sanitation procedures must be determined and described in detail as criteria for these CCPs. Once determined and precisely described, the daily monitoring can easily be carried out by visual observations and occasionally microbiological testing of cleaned surfaces (see also Section 5.1.3.A).
| Product flow | Hazard | Preventive measure | Degree of control |
|---|---|---|---|
| Live shrimp | |||
| Catch and catch handling | Black spots/ Excess chemical preservative (sulfite) | Correct treatment with preservative (sulfite) | CCP-2 |
| Chilling | Growth of bacteria | (Txt) control | CCP-1 |
| Transport | Growth of bacteria | (Txt) control | CCP-1 |
| Reception of raw materials | Substandard quality entering processing | Ensure reliable source, sorting | CCP-2 |
| Washing | |||
| Sorting | |||
| Cooking | Over-/undercooking (i.e. loss of yield and quality -survival of bacteria) | (Txt) control | CCP-1 |
| Peeling | |||
| Separation/cleaning | |||
| Freezing (IQF) | |||
| Packaging | |||
| All processing steps after cooking | Recontamination | Factory hygiene | CCP-2 |
| Water quality | CCP-1 | ||
| Sanitation | CCP-2 | ||
| Frozen storage | Loss of quality | Temperature control | CCP-2 |
The basis for canning is the use of thermal processing to achieve commercial sterility of the final product. The containers are distributed at ambient temperature and often stored for months, even years under these conditions. The content of the cans are normally eaten without any heating immediately before consumption. Thus the hazards related to this products are:
Survival of pathogens during heat processing.
Presence of heat-stable toxins (biotoxins, histamine) in the raw material.
Recontamination of product after heat processing (faulty containers, poor sealing, contaminated cooling-water, faulty container handling).
The Critical Control Points during production of canned fish are shown in Table 5.13.
The incoming raw material may be contaminated with biotoxins, histamine or toxic chemicals. There is no CCP–1 for these hazards during processing and proper control is therefore necessary at an earlier phase as described under Section 5.1.3.B. Similarly, the quality of the cans should be ensured by a documented quality assurance system by the can manufacturer. Additionally visual observations can be made. Guidance on visual inspection of cans will be found in Fisheries and Oceans (1983), AOAC/FDA (1984) and Thorpe and Barker (1984).
Correct filling is important to ensure proper heat penetration, hence it is a CCP.
A hermetically sealed container is a prime requirement, and control of this operation is paramount. Many types of closing machines are in use and it is essential that each machine is operating properly and trained mechanics keep them under control. Standards of can closure must be checked at regular intervals and always when setting up a new machine or following adjustment of an old one. It is normally recommended for metal cans, that tear down measurements be made once per shift and a formal/visual examination every half hour (ICMSF 1988, Varnam and Evans 1991). Details of seam examination may be obtained from Anon. (1973) and Hersom and Hulland (1980).
The thermal processing is a CCP–1 for eliminating all pathogenic organisms. Most processes are set to destroy spores of C. botulinum and are based on the so-called “botulinum cook” (Fo = 3, see Section 3.1). Monitoring of this CCP can be considered in 2 phases. The first concerns the pre-processing operations such as control of product temperature before retorting, control of time between container closure and retorting, loading of the retort, attachment of heat sensitive tape, venting of retort. The second phase is the thermal process.
This includes control of operational requirements such as steam pressure, water circulation and chain speed. The thermal processing should be timed from 2 points: the start of the heating and the point at which the sterilization temperature is reached. Properly calibrated thermometers must be used (platinum resistance thermometers are increasingly used as being the most accurate).
| Product flow | Hazard | Preventive measure | Degree of control |
|---|---|---|---|
| Raw material before entering the factory | See Table 5.6 | See Table 5.6 | See Table 5.6 |
| Reception of raw material at factory (fish and cans) | Substandard quality entering processing | Ensure reliable source Sensory evaluation | CCP–2 |
| Primary processing | |||
| Filling of cans | Uncontrolled heat penetration during thermal processing | Avoid inclusion of air, control weights of solids, liquids, product density and headspace | CCP–2 |
| Evacuation, seaming | Recontamination | Standards of closures must be checked at regular intervals | CCP–2 |
| Thermal processing | Survival of pathogens | (Txt) control | CCP–1 |
| Cooling | Recontamination | Quality of cooling water chlorine level > 1–2 ppm | CCP–2 |
| Handling of filled (wet) cans | Recontamination | Handling of warm, wet cans must be avoided Can handling should be designed to minimize mechanical shock | CCP–2 |
| Storage and distribution |
The ICMSF (1988) has summarized the monitoring requirements:
Date, code, product, container size, no. of cans in retort.
Time venting starts and ends.
Time sterilization temperature starts and ends.
Sterilization temperature (read from master thermometer).
Pressure at sterilization temperature.
Time steam off.
Elapsed time between steam on and off.
Time retort is opened.
Container status indicator check.
Name of retort operator.
Cross reference to recorder chart.
For other types of retorts, special problems may exist see FAO/WHO International code of practice for low–acid and acidified canned food (FAO/WHO 1979).
The cooling operation is a CCP–2 for preventing contamination by the cooling medium. A high standard of hygiene must be maintained and cooling water must be chlorinated. Before water is used for cooling, it should have at least 20 min. contact with 1–2 ppm. of free chlorine.
Residual chlorine measurements must also be made after cooling water has been in contact with cans. Additionally, microbiological analysis of the cooling water may be carried out. The mesophilic aerobic plate count must be less than 100 CFU/ml (ICMSF 1988).
The warm damp cans may readily be infected if exposed to excessive contamination in the area of the seams. Container handling is therefore a CCP-2. Handling of warm, damp cans should be avoided and possible contact surfaces must be thoroughly cleaned. Excessive physical handling of cans must also be avoided.
There are no hazards related to storage and distribution of final product. However, it is common practice - and in some cases a legal requirement (e.g. EEC Directive 91/493/EEC (EEC 1991b)) that checks must be carried out at random by the manufacturers to ensure that products have undergone appropriate heat treatment. This requirement is conveniently included as part of the verification procedures and involves taking random samples of the final product for:
Incubation tests. Incubation must be carried out at 37°C for seven days or at 35°C for ten days or at any other equivalent combination.
Microbiological examination of contents and containers in establishments laboratory or in another approved laboratory.
F. Semi-preserved fish
These are fish products with a salt content >6% NaCl (w/w) in the aqueous phase or a pH <5.0. Preservatives (sorbate, benzoate, nitrate) may or may not be added. These products still require chill storage and may have a shelf life of 6 months or more. Normally there is no heat-treatment applied neither during processing nor in the preparation before consumption. Traditional production often includes a long ripening period (several months) of the raw material before final processing. Product examples are salted and marinated fish, fermented fish and caviar products.
The contamination of these products with pathogenic bacteria is not a hazard. Also growth of these organisms is completely inhibited if storage temperature is kept <10°C. The mesophilic proteolytic C. botulinum (type A and B) and Staphylococcus aureus which are otherwise able to grow at the high NaCl-concentration in these products, cannot grow at temperatures below 10°C.
Nevertheless there is epidemiological evidence that these products have been the cause of a number of foodborne diseases related to the presence of biotoxins including histamine, bacterial toxins and parasites.
C. botulinum toxins are stable at high salt and low pH (Huss and Rye Petersen 1980). Thus any toxin present or performed in the raw material will be carried over to the final product. These hazards can only be controlled by having full control over the raw material handling as described under Section 5.1.3.B. If this is not possible, the raw materials for this production is a CCP–2, but methods for monitoring are very limited. A sensory evaluation will give some indication - but no guarantee that no toxin (histamine, botulinum toxin) is present.
In contrast, the presence of live parasites in these products is a hazard which can easily be controlled. The requirements for salt level and holding times are presented in Section 3.4 and if these cannot be met, a freezing step must be included as mentioned for lightly preserved fish (this Section). An example of CCPs in processing of semipreserved fish is shown in Table 5.14.
G. Dried, dry-salted, smoke-dried fish
These are products with very high salt content (saturated NaCl in water phase) and/or very low water activity due to drying. The products are stable at ambient temperature and may be eaten after rehydration and cooking or directly without any cooking. The hazard related to processing is primarily a time factor. Processing takes place at ambient temperature, and if lowering of water activity takes too long, growth and toxin production by microorganisms will take place.
However, hazards related to the raw materials (production of bacterial toxins and histamine, presence of biotoxins and chemical toxins) may also be carried over to the final products. These hazards must be controlled as described for “raw materials for further processing”.
Salted or dried fish may spoil due to growth of halophilic bacteria (“pink”) or moulds (“dun”). These microorganisms may be introduced with the salt or via contamination from poorly cleaned equipment and utensils used during processing. Prevention measures (CCP–2s) are good factory hygiene and sanitation, and if possible, storage at <10°C, which is a CCP–1 for this hazard.
| Product flow | Hazard | Preventive measure | Degree of control |
|---|---|---|---|
| Raw materials before entering the factory | See Table 5.6 | See Table 5.6 | See Table 5.6 |
| Reception of raw material at factory | Substandard quality entering processing | Ensure reliable source Sensory evaluation | CCP–2 |
| Primary | |||
| processing | |||
| Filleting | |||
| Salting in brine | Incorrect salt content in fish (spoilage and/or survival of parasites) | Control of salt concerntration in brine and time for fish in brine (NaCl concentration and holding time to be specified). | CCP–1 |
| Marinating | Incorrect NaCl and acetic acid concerntration in fish (taste, spoilage and/or survival of parasites) | Control of composition of marinade and marinating time. Holding time to be specified | CCP–1 |
| Secondary processing | |||
| Packaging in glass jars in final pickle | Poor sensory quality | Control of composition of pickle(concentration of sugar, acetic acid, spices, etc.) | CCP–1 |
| Distribution | Growth of microorganisms (bacteria, yeasts) (spoilage, toxin production by C. botulinumtype A, B). | (Control of temperature T< 10°C) | CCP–1 |
The HACCP-concept has been applied very successfully by the U.S. Food and Drug Administration (FDA) since 1973 in the control of microbiological hazards in low acid canned food (FDA 1973). No other regulatory agency considered including HACCP in their food safety programs until it was strongly recommended by a subcommittee on microbiological criteria set up by the U.S. National Research Council (FNB/NRC 1985). Following that, the U.S. National Marine Fisheries Service investigated the mandatory use of HACCP in the seafood industry in a study entitled the “Model Seafood Surveillance Project” (Garrett and Hudak Roos 1991). Also in Canada, a new Quality Management System which embodies the HACCP philosophy, has been introduced and mandatory since February 1993 (White and Noseworthy 1992).
The principles of HACCP can easily be incorporated into national fish regulations, but it should be emphasized that HACCP deals with the uniqueness, while regulatory agencies are used to deal with the general issues which can be formulated in regulations to cover the whole industry. A HACCP system needs to be tailored to each individual plant and each processing line. This calls for close cooperation between regulatory agencies and food industry, which is not easy to achieve. Highly educated people and staff trained in the application of HACCP are needed, as well as mutual respect, understanding and trust - on both sides.
Once established, each particular plant needs to have the system approved by the regulatory authority having jurisdiction. All CCPs and monitoring records can then be checked by inspectors and compliance with safe processing requirements can easily be confirmed. As a further guarantee, the regulatory agencies may also occasionally carry out verification tests to ensure that the HACCP system is working. The U.S. National Advisory Committee on Microbiological Criteria for Foods (NACMCF 1992) has stated that governments' regulatory responsibility is part of the verification activities and give the example shown below:
Examples of verification activities
A. Verification procedures may include:
Establishment of appropriate verification inspection schedules.
Review of the HACCP plan.
Review of CCP records.
Review of deviations and dispositions.
Visual inspections of operations to observe if CCPs are under control.
Random sample collection and analysis.
Review of critical limits to verify that they are adequate to control hazards.
Review written records of verification inspections which certifies compliance with the HACCP plan or deviations from the plan and the corrective actions taken.
Validation of HACCP plan, including on-site review and verification of flow diagrams and CCPs.
Review of modifications of the HACCP plan.
B. Verification inspections should be conducted:
Routinely, or on an unannounced basis, to assure selected CCPs are under control.
When it is determined that intensive coverage of a specific commodity is needed because of new information concerning food safety.
When foods produced have been implicated as a vehicle of foodborne disease.
When requested on a consultative basis or established criteria have not been met.
To verify that changes have been implemented correctly after a HACCP plan has been modified.
C. Verification reports should include information about:
Existence of a HACCP plan and the person(s) responsible for administering and updating the HACCP plan.
The status of records associated with CCP monitoring.
Direct monitoring data of the CCP while in operation.
Certification that monitoring equipment is properly calibrated and in working order.
Deviations and corrective actions.
Any samples analyzed to verify that CCPs are under control. Analyses may involve physical, chemical, microbiological or organoleptic methods.
Modifications to the HACCP plan.
Training and knowledge of individuals responsible for monitoring CCPs.
Regulatory agency and industry cooperation can provide industry and governments control systems as well as potential buyers of the products with the necessary confidence in the quality assurance programme. Once the confidence is established, the entrance of such products to the world market can be significantly simplified by means of the signing of M.O.U.s (Memorandum of Understanding) between countries and between importers and exporters. One further advantage is that duplicating control effort can be avoided resulting in cost/benefit value to both parties.
A particularly sensitive issue in this process is that regulatory agencies must have access to industry records. This point of major disagreement needs to be resolved. There can be no discussion that the regulators should have access to monitoring results of CCPs and actions taken, while some information related to manufacturing practices may be proprietary.
The great advantage of the HACCP-system is that it constitutes a systematic, structural, rational, multi-disciplined, adaptable and cost-effective approach of preventive quality assurance. Properly applied, there is no other system or method which can provide the same degree of safety and assurance of quality and the daily running cost of a HACCP system is small compared with a large sampling programme.
By using the HACCP-concept in food processing it is possible to assure and to document assurance of minimum quality standard such as:
Absolutely safe food. If absolute safety cannot be guaranteed (e.g. consumption of raw molluscs), it is clearly disclosed by the programme, and a general warning should be given.
Products having a stated and agreed (normal) shelflife, if handled and stored according to instructions.
Further advantages which are evident from the text (Mitchell 1992) have been listed and summarized:
Control is proactive in that remedial action can be taken before problems occur.
Control is by features that are easy to monitor, such as time, temperature and appearance.
Control is fast such that prompt remedial action can be taken if necessary.
Control is cheap in comparison with chemical and microbiological methods of analysis.
The operation is controlled by those persons directly involved with the food.
Many more measurements can be taken for each batch of product because control is focussed at the critical points in the operation.
HACCP can be used to predict potential hazards.
HACCP involves all levels of staff in product safety, including non-technical personnel.
The general principle of the HACCP-concept is to direct energy and resources towards areas where they are necessary and most useful (i.e. “distinguish between the nice and the necessary”). This idea makes HACCP an ideal tool where resources are scarce as is the case in many developing countries. It may appear an immense and impossible target to upgrade an underdeveloped industry to be able to produce safe food for export. However, by using the HACCP-concept it is possible to identify the necessary changes in procedures and/or new installations.
For small plants, processing fresh fish only, all that is needed may be absolute temperature control from catching/landing to distribution (see also Section 7.5).
However, as the HACCP concept was developed more than 20 years ago, it is a very relevant question to ask: Why is it that this system is not in general use all over the world? The following are some problems that need to be considered (Tompkin 1990):
There continues to be a non-uniform understanding of HACCP both nationally and internationally. New definitions and principles are evolving as a result of extensive debate. At times it appears that principles are reversed to extensive sampling and “regulation” of every minute detail. Producer-buyer and producer-regulator disagreements over end-product testing will not disappear and difference of opinion will exist over the degree to which HACCP can replace the need for end-product testing.
There is no universal agreement on what constitutes a hazard (e.g. presence of Listeria monocytogenes in raw food). There is an urgent need to establish an international body consisting of members being non-political, but highly respected scientifically, who can advise on safety issues and current scientific thinking on hazards in foods.
To be effective, HACCP needs to be applied from origin of food (sea/farm) to consumption. This may not always be possible.
HACCP deals with the uniqueness - regulations with the general. This problem may be difficult for regulatory agencies to understand and accept, thereby delaying the application of the system.
Acceptance of HACCP requires mutual trust. Unless this trust exists or can be created between the regulator and the regulated, the system will fail.
HACCP requires processors to accept greater responsibility. This may cause some resistance from processors who normally rely on government services (inspectors, laboratories) to guarantee for safety and quality. Furthermore, it can lead to a perception that HACCP results in reduced inspection and loss of regulatory control even though the intent of HACCP is just the opposite.
It will take a long time to train inspectors and industry personnel to arrive at one common understanding of HACCP.
Application of HACCP will not prevent all problems, and “experts” may disagree on vital issues.
The decisions and priorities on issues related to health hazards are influenced by a number of factors. The scientific community can only provide one dimension, and even requires that all sound scientific data can be uniformly interpreted. However, the risk perception and emotional feelings by the consumers are often quite different and the producers are by nature mostly concerned about cost and competing markets.
The legislative and regulatory authorities are the institutions who must sort the information and set the rules. This means that these agencies must be staffed with highly educated and trained people, who can keep abreast with the latest scientific development. These institutions must be completely independent from commercial and other interests which may affect their decisions and also try to avoid the bureaucratic pitfalls spending all their time and effort making regulations and controlling matters of minor importance such as tiles on the walls, types of watertaps to be used and the numbers of doors leading into a particular room. Such non-HACCP attitudes by regulatory agencies may be further aggravated in a democracy, where these agencies may overreact to minor health hazards about which there is a strong public concern, while taking little or no action in regard to health hazards that scientists have demonstrated to be of major importance, but arousing little public concern (Mossel and Drake 1990). A typical example is the large public concern and exaggerated regulatory response regarding authorized food additives, while this scientifically is identified as a minor problem.
In conclusion, it can be stated that for the HACCP concept to be truly operational and generally applied there is a great need for increased communication and understanding between the scientific community, the general public and the regulatory agencies. Only then can a better prevention of foodborne diseases be achieved.
