5.1 Definition of Q.A.
5.2 Microbiological testing
5.3 What are the other options?
5.4 The HACCP concept
5.5 The ISO-9000 series certification of the International Standards Organization
From the outset, a distinction needs to be drawn between Quality Assurance and Quality Control as the difference between them has been blurred due to indiscriminate use of these two terms. According to the International Standards Organization (ISO), Quality Assurance (Q.A) consists of all those planned and systematic actions necessary to provide adequate confidence that a product or service will satisfy given requirements for quality. In other words it is a strategic management function which establishes policies, adapts programmes to meet established goals and provides confidence that these measures are being effectively applied. Quality Control (Q.C) on the other hand consists of the operational techniques and activities that are used to fulfil requirements for quality. It is a tactical function which carries out the programmes established by Q.A.
Proper handling of fish between capture and delivery to the consumer is a crucial element in assuring final product quality. Standards of sanitation, method of handling and the time/temperature of holding fish are all significant quality factors. With a few exceptions, fish are considered free of pathogenic bacteria of public health significance when first caught. The presence of bacteria harmful to man generally indicates poor sanitation in handling and processing and the contamination is almost always of human or animal origin. Salmonellae have been found in fish washed with polluted water and from fish-holds washed with polluted water. Contamination may take place when the fish are gutted at the quayside in a dirty harbour. In many BOBP countries, shrimp are sun-dried at the landing place and are targets for contamination by bird droppings and animal excreta. Sun-dried materials are known to have a high rate of contamination with salmonellae.
A number of microbiological tests of fish and fish products are used by authorities to check that the microbiological status is satisfactory. The purpose of these tests is to detect pathogenic bacteria (Salmonella, Staphylococcus aureus, E. coli) or indicator organisms of fecal pollution (fecal coliforms, fecal streptococci) or other types of general contamination or poor handling practices (coliform bacteria, faecal streptococci, total viable count). Microbiological testing can be costly and time-consuming. Estimation of bacterial numbers in fish is frequently used to retrospectively assess microbiological quality or to assess the presumptive safety of the product. The number, size and nature of the samples greatly influence the results and even the most elaborate sampling cannot guarantee the safety of the product. However, it is still worthwhile; if substandard consignments are found, the psychological effect on the seller is high, especially if the consignment is deemed for export to countries that have established microbiological criteria.
Sampling plan and recommended microbiological limits for seafood (ICMSF 1986)
Table 5-1
|
Product |
Test |
Case |
Plan Class |
no. of samples |
no. of positive results |
Limit per gram or per cm2 |
|
|
m |
M |
||||||
|
Fresh and frozen fish |
APC |
1 |
3 |
5 |
3 |
5 x 105 |
107 |
|
E. Coli |
4 |
3 |
5 |
3 |
11 |
500 |
|
|
Precooked breaded fish |
APC |
2 |
3 |
5 |
2 |
5 x 105 |
107 |
|
E. Coli |
5 |
3 |
5 |
2 |
11 |
500 |
|
|
Frozen raw crustaceans |
APC |
1 |
3 |
5 |
3 |
106 |
107 |
|
E. Coli |
4 |
3 |
5 |
3 |
11 |
500 |
|
|
Frozen cooked crustaceans |
APC |
2 |
3 |
5 |
2 |
5 x 105 |
107 |
|
E. Coli |
5 |
3 |
5 |
2 |
11 |
500 |
|
|
S. aureus |
8 |
2 |
5 |
0 |
103 |
- |
|
|
Cooked, chilled, and frozen crabmeat |
APC |
2 |
3 |
5 |
2 |
105 |
106 |
|
E. Coli |
6 |
3 |
5 |
1 |
11 |
500 |
|
|
S. aureus |
9 |
2 |
5 |
0 |
103 |
- |
|
|
Fresh and frozen bivalve molluscs |
APC |
3 |
2 |
5 |
0 |
5 x 105 |
- |
|
E. Coli |
6 |
2 |
5 |
0 |
16 |
- |
|
Table 5-2: INSPECTION PROCEDURE FOR IMPORTED FOOD IN JAPAN
Source: Import food. 1990, Japan Food Hygiene Association (1991)
Table 5-3: MICROBIOLOGICAL TESTS INCLUDED IN THE MICROBIOLOGICAL STANDARDS AND REGULATIONS OF A TYPICAL EU COUNTRY
|
|
France |
|
|
Raw fish, fillets, fresh/frozen |
1, 2, 7, 10, 11* |
|
|
Semi preserves |
||
|
|
pasteurized |
1, 2, 7, 10, 11 |
|
|
non-pasteurized |
1, 2, 7, 10, 11 |
|
Smoked salmon |
1, 2, 7, 10, 11 |
|
|
Crustacean |
||
|
|
raw |
1, 3, 7, 11 |
|
|
cooked |
1, 3, 7, 11 |
|
|
cooked and |
1, 3, 7, 10 |
|
|
peeled |
11 |
|
Molluscs |
||
|
|
live |
3, 4, 7 |
|
|
raw |
- |
|
|
pre-cooked |
1, 3, 7, 10, 11 |
* The figures refer to tests for:1. Aerobic plate count (TVC)
2. Coliforms
3. Fecal coliforms
4. Fecal streptococci
5. Enterococci
6. E. Coli
7. Salmonella
8. Shigilla sp.
9. Total enterobacteriaceae
10. Staphylococcus aureus
11. Anaerobic sulfite red.
Table 5.4: STANDARDS AND CRITERIA OF FISH AND FISHERY PRODUCTS UNDER THE FOOD SANITATION LAW, JAPAN.
|
CLASSIFICATION |
STANDARDS AND CRITERIA |
REMARKS |
|
Fish paste products (fish sausage and ham) |
- Coliform organism: negative/g |
There are also processing & preservation standards
|
|
Salted salmon roe |
- Nitrite radical: 0: 005 g/kg or less |
|
|
Boiled octopus |
- Viable Bacteria count: 1.0 x 105/g or less |
Only frozen octopus. There are also processing & preservation standards* |
|
Raw oyster for uncooked |
- Viable Bacteria count: 5.0 x 104/g or less |
There are also processing & preservation standards |
Table 5-5: COMPILATION OF LEGAL LIMITS FOR HAZARDOUS SUBSTANCES IN FISH AND FISHERY PRODUCTION IN JAPAN
|
ITEMS |
STANDARDS |
|
Mercury (Hg)
|
0.4 ppm (Total Hg) |
|
0.3 ppm (Methyl Hg) |
|
|
* weekly intake is supposed not to be above 170 m g methyl Hg for an average adult weighing 50 kg. Diets of pregnant women and children should be more strictly controlled. |
|
|
PCB |
Offshore fish (edible portion): 0.5 ppm |
|
Inland sea fish (edible portion): 3 ppm |
|
|
Dieldrin (including aldrin), pesticide |
0.1 ppm (hard-shelled mussels only) |
|
Paralytic shellfish poison, |
4 MU |
|
Diarrhetic shellfish poison, (shellfish poison) |
0.005 MU |
|
* 4 Mouse Unit (MU) _ 80 ug/100 g (saxitoxin) |
The following table will serve as a guide for the harbour manager.
Table 5-6: GUIDELINES FOR PATHOGENS
|
Total viable count |
Not to exceed 100,000 per gram |
|
Salmonella |
Not to be detected in 25g of meat |
|
E. Coli |
Less than 10 per gram |
|
S. aureus |
Less than 1000 per gram |
|
Faecal coliforms |
None |
While cost considerations and the availability of testing facilities locally may preclude the establishment of microbiological testing in the fishery harbour complex, other methods should be used by the harbour master to assure a reasonable degree of protection for both consumer and supplier against risks associated with microbial contamination within the harbour complex.
Preventive strategies based on thorough analysis of prevailing conditions are much more likely to provide an assurance of fish quality. The Hazard Analysis Critical Control Point (HACCP) system is one such strategy. In recent years a number of other quality systems have been introduced, such as certification under an Internationally Accepted Standard (ISO 9000 series) and Total Quality Management (TQM). The main reasons to implement such quality systems are:
i. To improve the efficiency and profitability of their operations and the quality of the product.ii. To satisfy a requirement from the customer/importer.
iii. To provide defence in legal actions
iv. To keep up with the competition.
5.4.1 HACCP system for fresh and frozen fish products
5.4.2 Application of HACCP system in fishery harbours
5.4.3 Checklist for ensuring seafood safety
5.4.4 Advantages of the HACCP system
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 of HACCP. The system offers a rational and logical approach to control food hazards and avoid the many weaknesses inherent in the inspectional approach. Once established, the main effort of the quality assurance programme will be directed towards the Critical Control Points (CCPs) and away from endless final product testing. This will assure a higher degree of safety and at less cost.
The main elements of the HACCP system are:
· Identify potential hazards. Assess the risk of occurrence.
· Determine the Critical Control Points (CCPs)
· Establish criteria to be met to ensure that each CCP is under control.
· Establish a monitoring system.
· Establish corrective action when CCP is not under control.
· Establish procedures for verification.
· Establish documentation and record-keeping.
Identification of potential hazards: Hazards have been defined 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. In other words a hazard is a biological, chemical or physical property that may cause food to be unsafe for consumption. For inclusion in the list, hazards must be of such a nature that their elimination or reduction to acceptable levels is essential for the production of safe food.
Hazard analysis requires two essential ingredients. The first is the appreciation of the pathogenic organisms that could harm the consumer or cause spoilage. The second is a detailed understanding of how these hazards could arise. In order to be meaningful, hazard analysis must be quantitative. This requires an assessment of both severity and risk. Severity refers to the serious consequences when a hazard occurs, while risk is an estimate of the likelihood of a hazard occurring. It is only the risk that can be controlled.
Determine the CCPs: A CCP is a location, procedure or processing step at which hazards can be controlled. CCP1 is that which will ensure full control of a hazard and CCP2 is that which 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 preventive measures. If an identified hazard has no preventive measure at a certain step then no CCP exists at that step.
Establish criteria, target levels and tolerances for each CCP: To be effective, a detailed description of all CCPs is necessary. This includes determination of criteria and specified limits or characteristics of a physical, chemical or biological nature which ensure that a product is safe and of acceptable quality.
Establish a monitoring system for each CCP: The monitoring should be able to detect deviations from specifications or criteria 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 a monitoring interval that will be reliable enough to indicate whether the hazard is under control. Periodic verification of sanitation controls and random microbiological tests of fish can be very valuable as means of establishing and verifying the effectiveness of control at CCPs.
Corrective actions: The system must allow for corrective action to be taken immediately when monitoring results indicate that a particular CCP is not under control. Action must be taken before the deviation leads to a safety hazard.
Verification and documentation: Verification is the use of supplementary information to check whether the HACCP system is working. Procedures may include review of CCP records, review of deviations, random sample collection and analysis. Inspections should be conducted routinely or unannounced, when the fish originating from the harbour complex is implicated as a vehicle of food-borne disease, or when requested on a consultative basis.
The hazard analysis for these products is fairly straightforward and uncomplicated. The live animals are caught in the sea, handled and processed without any use of additives or chemical preservatives and finally distributed with icing or freezing as the only means of preservation. Contamination with pathogenic bacteria from the human/animal reservoir can occur when the landing place is unhygienic or when the fish are washed with contaminated water. Most fish and crustaceans are cooked before eating although a few countries have a tradition of eating raw fish. Cooking the product before consumption usually eliminates the risk from contamination with pathogenic bacteria. However, an indirect hazard exists if contaminated products are polluting the working areas and thereby transporting the pathogens to products which are not cooked before eating (cross contamination). Cooking will not, however, eliminate the growth of heat-stable toxins (histamine).
Time and temperature conditions at all steps from capture of fish to distribution constitute a CCP1 in preventing growth of pathogenic bacteria and spoilage bacteria. Below 1°C, no growth of pathogenic bacteria takes place. Therefore a maximum time at temperatures over 5°C must be specified in the criteria for this CCP. Exposure for only a few hours of fatty fish to the sun, air and ambient temperature during fish handling on the vessel or at the harbour is sufficient to introduce severe quality loss and cause early spoilage.
A sensory assessment (appearance, odour) of the fish when landed is a CCP2 for ensuring that until this point the material has been under control, and that spoiled fish or shrimp and potential toxic species can be discarded.
Personal hygiene as well as fishery harbour sanitation are CCPs preventing contamination of products with micro-organisms and filth. The seriousness of the hazard varies, depending on the intended end-use of the product (cooking or no cooking). Occasionally a microbiological check of the cleanliness of working surfaces can be made. This control procedure must be carried out on a weekly basis. When the routines are well established, microbiological control of cleanliness can be carried out monthly.
Water quality is a CCP1 in preventing contamination from this source. Where in-plant chlorination is used, chlorine levels must be measured and recorded. Chlorine levels should be measured daily.
Harbours vary a great deal in size and the quantities of fish they handle. Accordingly the hygienic requirements and the design of fish handling areas may vary considerably. Quite obviously the requirements of a small harbour or landing place where fish is landed, repacked in ice and distributed to the local market are different from the hygienic requirements of a large complex which includes fish processing of a variety of seafood and cold storage. In most fishery harbours where there is no seafood processing other than handling of fresh fish, all that is needed may be temperature and water quality controls besides encouraging a cleanliness ethic.
1. Landed fish should not be exposed to the sun and should be iced.2. Inspect fish for appearance and odour and reject fish of unacceptable quality.
3. Periodically perform bacteriological tests on representative samples.
4. Follow a cleaning schedule for all work areas and surfaces, using water containing 5 to 10 ppm of free chlorine.
5. Remove all fish slime and blood by hosing down with chlorinated water. At the end of the day, rinse all surfaces with clean water having 5 ppm of chlorine.
6. Apply personal hygiene rules strictly to prevent contamination of fish. Smoking and spitting in work areas should not be permitted. Hands must be washed with bactericidal soap prior to handling fish and after a visit to the toilet.
7. Check that water supply and treatment systems are in order. Water and ice samples should be analysed as per testing schedule by ISO certified laboratories for levels of chemical and bacteriological contamination and potability certificates obtained.
8. The harbour should be free from litter and other wastes.
9. Check to ensure that all drainage systems are in good working order.
10. The harbour should be free of animals, rodents and pests.
11. Ensure that there are no bird nests in the fish handling area.
12. Check that wastes are being disposed of sanitarily.
13. Check cold storage equipment to ensure that the right temperature is being maintained.
14. Ensure that all precaution and warning signs are readable.
The HACCP system is an ideal tool when resources are scarce. The general principle of the HACCP concept is to direct energy and resources towards areas where they are necessary and most useful.
The main advantages can be summarized as follows:
· Control is proactive in that remedial action can be taken before a problem occurs.· Control is through features that are easy to monitor such as time, temperature and appearance.
· Control is cheap in comparison with detailed chemical and microbiological analysis.
· The operation is controlled by persons directly involved with the fish product.
· It can be used to predict potential hazards.
For seafood processing establishments, the most relevant standards of the ISO 9000 series are the ISO 9001 and 9002. The former is a quality system standard that lays down requirements for product development, production, delivery and after sales functions. The latter concerns only production and delivery. The ISO 9003 deals with quality system requirements for final inspection and testing.
ISO 9000 standards comprise many elements. Of these, management responsibility and commitment is the first and most important element. The next element is the presence of a documented quality system organized in three levels comprising the Quality Manual, Procedures and Instructions. Process control is another requirement to ensure that all processes influencing the quality of the final product are specified and documented in detail. The schedule of testing and inspection and the test equipment used should demonstrate acceptable compliance with the defined specifications. A corrective action system concerned with revising work operations should be in place to try and eliminate the causes of failure. Quality records including inspection reports, analytical results and corrective action reports should be maintained. Internal quality audits on a regular basis is another requirement. Training of staff, personal hygiene, cleaning and disinfection are a vital part of the ISO 9000 standards with particular reference to the food industry.
The work involved in establishing and implementing a quality system like ISO 9001 or 9002 should not be under-estimated. It is a very demanding project in terms of time and resources. (See Figure 63). The time required is often 1-2 years even for a medium-sized establishment.
Marketing merits, reduced quality costs and higher efficiency are the main advantages of the quality system that contribute to a higher profitability. The main objective of quality management according to the ISO 9000 series is meeting the agreed requirements of the customer. This underlines that the quality of a company's products is the key factor in a company's performance.
Quality systems such as the ISO 9000 series serve to establish confidence in the customer. Once confidence is established, entry into world markets is simplified.
Table 5.7: PHASES OF A QUALITY SYSTEM APPROACH
|
Formation of a quality management group |
